DESC:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION

(See Section 10 and Rule 13)

Title of invention:
A SYSTEM AND METHOD FOR AUTO-CONTROLLING ABS DURING DIFFERENTIAL LOCKING IN ALL WHEEL DRIVE VEHICLES

Applicant:
BEML Limited
A company Incorporated in India under the Companies Act, 1956
Having Address As:
BEML Soudha, 23/1, 4th Main,
Sampangirama Nagar, Bengaluru - 560 027,
Karnataka, India

The following specification particularly describes the invention and the manner in which it is to be performed.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY
[001] The present invention claims priority from Indian patent application numbered IN 202241052552 filed on 14th September, 2022.
FIELD OF THE INVENTION
[002] The present subject matter described herein generally relates to a system and method for auto-controlling ABS during differential locking, and more specifically for a system and method for auto-controlling of ABS (Anti-Lock Braking System) during differential locking in all wheel drive vehicles.
BACKGROUND
[003] Anti-lock braking system (ABS) is made as standard fitment in all vehicles. To avoid wheel locking and better braking performance ABS system is equipped in all heavy duty trucks. Generally vehicles designated to be used in off-highway, may not be equipped with ABS systems as the vehicles are installed with the differential / inter axle lock provision to perform in unfavorable conditions. Such exceptional driving situations are particularly important for off-road vehicles whose braking performance on gravel like roads gives rise to complaints. The braking power of a blocked wheel is relatively high on such road surfaces. When a switch-off option for the ABS is provided in such off-road vehicles in order to ensure the maximum deceleration in off-road operation. The switch-off option is critical. If the front wheels are locked, the vehicle is no longer steerable. The driving stability reduces when the rear wheels are locked.
[004] Hence to overcome the aforesaid drawbacks there is a requirement to automatic control of ABS system.
OBJECTS OF THE INVENTION
[005] Main object of the present disclosure is to provide a system and method for auto-controlling ABS during differential locking to control the ABS during differential lock and off- highway operations.
[006] Another object of the present disclosure is to provide a system and method for auto-controlling ABS during differential locking to prevent wheel locking during excessive braking or panic braking.
[007] Yet another object of the present disclosure is to provide a system and method for auto-controlling ABS during differential locking to maintain the stability of the vehicle.
[008] Yet another object of the present disclosure is to provide a system and method for auto-controlling ABS during differential locking when the vehicle is fitted with manual slack adjuster.
[009] Another object of the present disclosure is to provide a system and method for auto-controlling ABS during differential locking which is compact, cost effective and easy to implement.
SUMMARY
[0010] Before the present system is described, it is to be understood that this application is not limited to the particular machine, device or system, as there can be multiple possible embodiments that are not expressly illustrated in the present disclosures. It is also to be understood that the terminology used in the description is for the purpose of describing the particular versions or embodiments only, and is not intended to limit the scope of the present application. This summary is provided to introduce aspects related to a system and method for auto-controlling ABS during differential locking in all wheel drive vehicle, and the aspects are further elaborated below in the detailed description. This summary is not intended to identify essential features of the proposed subject matter nor is it intended for use in determining or limiting the scope of the proposed subject matter.
[0011] The present subject matter discloses a system for auto-controlling ABS during differential locking in all wheel drive vehicles comprising atleast one pole wheel assembly with atleast one sensor fixedly mounted on atleast one axle to sense the wheel speed. A controller provided to receive input signal from said atleast one pole wheel assembly to modulate the brake application by atleast one modulator valve. A differential / inter-axial lock switch provided in the vehicle cabin. Atleast 6sensor- 6modulator (6S6M) ABS system is provided to regulate and modulate the application of brake and brake pressure to avoid wheel locking.
[0012] A method for auto-controlling ABS during differential locking in all wheel drive vehicles comprising the steps of a compressor is operated by an engine for generating pressurized air. The moisture contents are removed through an air dryer and maintaining the system pressure. Wherein the air dryer operates as a safety valve. The compressed air is stored in a main reservoir. A system protection valve is fitted with inbuilt non return valves for ensuring system safety and supplying air to a service reservoirs. Signal from the dual brake valve is transmitted to the service brake valve. Wherein the brakes are applied using the air from the service reservoirs. The wheel rotations is sensed by the wheel speed sensors and locking conditions. Wherein the wheel speed sensors sends the signal input to the ABS ECU. A: to regulate and modulate the application of brake and brake pressure to avoid wheel locking by the ABS ECU with atleast one modulator valve on detection of differential locking disengaged. Or B: disconnected the ABS ECU electrically by interrupting the ignition power to the ECU through a relay on detection of differential locking engaged.
STATEMENT OF INVENTION
[0013] The present subject matter discloses a system for auto-controlling ABS during differential locking in all wheel drive vehicles comprising atleast one pole wheel assembly with atleast one sensor fixedly mounted on atleast one axle to sense the wheel speed. A controller provided to receive input signal from said atleast one pole wheel assembly to modulate the brake application by atleast one modulator valve. A differential / inter-axial lock switch provided in the vehicle cabin. Atleast 6sensor- 6modulator (6S6M) ABS system is provided to regulate and modulate the application of brake and brake pressure to avoid wheel locking.
[0014] In an embodiment, said all-wheel drive vehicle is provided with a 8X8 all-wheel drive heavy duty vehicle (HDV) with independent swing axles and 6Sensor - 6Modulator (6S6M) configuration for anti-lock braking system (ABS).
[0015] In an embodiment, said atleast one pole wheel assembly is provided with atleast one sensor, atleast one sensor holder and atleast one mounting bracket.
[0016] In an embodiment, the controller is an anti-lock braking system electronic control unit (ABS ECU).
[0017] In an embodiment, the differential / inter-axial lock switch is a pneumatic type switch.
[0018] In an embodiment, the 6S6M ABS system is a pneumatic system comprising a compressor, a condensate pump, an air dryer, a main reservoir, a system protection valve, a service brake valve, a dual brake valve, atleast one modulator valve, a brake booster.
[0019] In an embodiment, the 6S6M configuration is provided with four modulator valves to modulate brake pressure on each wheel of the rear axles R1, R2 and one modulator valve to modulate brake pressure on left hand (LH) side wheels of the front axle F1, F2 and another modulator valve to modulate brake pressure on right hand (RH) side wheels of the front axle F1, F2.
[0020] In an embodiment, the 6S6M configuration is provided with four sensors mounted on each wheel of the rear axles R1, R2 and two sensors mounted on each wheel of the front axle F1 to sense the wheel speed through magnetic pickup.
[0021] In another embodiment, a method for auto-controlling ABS during differential locking in all wheel drive vehicles comprising the steps of a compressor is operated by an engine for generating pressurized air. The moisture contents are removed through an air dryer and maintaining the system pressure. Wherein the air dryer operates as a safety valve. The compressed air is stored in a main reservoir. A system protection valve is fitted with inbuilt non return valves for ensuring system safety and supplying air to a service reservoirs. Signal from the dual brake valve is transmitted to the service brake valve. Wherein the brakes are applied using the air from the service reservoirs. The wheel rotations is sensed by the wheel speed sensors and locking conditions. Wherein the wheel speed sensors sends the signal input to the ABS ECU. A: to regulate and modulate the application of brake and brake pressure to avoid wheel locking by the ABS ECU with atleast one modulator valve on detection of differential locking disengaged. Or B: disconnected the ABS ECU electrically by interrupting the ignition power to the ECU through a relay on detection of differential locking engaged.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The foregoing summary, as well as the following detailed description of embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the disclosure, there is shown in the present document example constructions of the disclosure, however, the disclosure is not limited to the specific methods and device disclosed in the document and the drawing. The detailed description is described with reference to the following accompanying figures.
[0023] Figure 1 illustrates a 6Sensor - 6Modulator ABS system pneumatic circuit diagram of a system for auto-controlling ABS during differential locking in all wheel drive vehicles, in accordance with an embodiment of the present subject matter.
[0024] Figure 2 illustrates a diagram showing the location of the modulator valves and the wheel speed sensors of the system for auto-controlling ABS during differential locking in all wheel drive vehicles, in accordance with an embodiment of the present subject matter.
[0025] Figure 3 illustrates a block diagram of an ECU and the electrical schematic connections of the system for auto-controlling ABS during differential locking in all wheel drive vehicles, in accordance with an embodiment of the present subject matter.
[0026] Figure 4 illustrates a flowchart for the sequence of the method for auto-controlling ABS system during differential locking in all wheel drive vehicles, in accordance with an embodiment of the present subject matter.
[0027] The figures depict various embodiments of the present disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION OF INVENTION
[0028] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words "comprising", “having”, and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Although any devices and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the exemplary, devices and methods are now described. The disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms.
[0029] Various modifications to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of ordinary skill in the art will readily recognize that the present disclosure is not intended to be limited to the embodiments illustrated, but is to be accorded the widest scope consistent with the principles and features described herein.
[0030] The present subject matter discloses a system (100) for auto-controlling ABS during differential locking in all wheel drive vehicles as shown in figure 1. The vehicles used on off-highway are normally not equipped with ABS system. However, as per the present disclosure to avoid wheel locking and for better braking performance ABS system is required to be equipped in all heavy duty vehicles. The 8X8 all wheel drive heavy duty vehicle (HDV) are designed with independent swing axles and provided with 6Sensor - 6Modulator configuration for Anti-lock braking system. The vehicles are enabled with differential/ inter axle locking provision to perform in unfavorable conditions.
[0031] Further, the system (100) comprises atleast one pole wheel assembly, atleast one modulator valve (114, 118, 120, 122, 124, 126), a controller (302), a diagnosis switch, an ABS Off Road switch, a differential / inter-axial lock switch, an ABS warning lamp, a relay and a fuses. The pole wheel assembly comprises atleast pole wheel, atleast one pole wheel sensor (202, 204, 206, 208, 210, 212), atleast one pole wheel sensor holder, atleast one mounting bracket. The pole wheel is mounted permanently on the axles used for sensing wheel speed. The pole wheel sensor (202, 204, 206, 208, 210, 212) senses the wheel speed by magnetic pickup. The pole wheel sensor holder with mounting bracket holds the pole wheel sensor (202, 204, 206, 208, 210, 212) rigidly. The modulator valve (114, 118, 120, 122, 124, 126) is used to modulate the brake application based on the controller (302) input signal. The controller (302) is an ABS ECU which activates the modulator valve (114, 118, 120, 122, 124, 126) based on the input from the pole wheel sensor (202, 204, 206, 208, 210, 212). The differential / inter-axial lock switch is located in the cabin and is a pneumatic type switch. An electrical wiring harness (Chassis, Cabin and Interface wire harness) are used for all the electrical connection of all the sensors (202, 204, 206, 208, 210, 212), the modulator valves (114, 118, 120, 122, 124, 126), the power supply and signals connections to the ECU. The 6S6M ABS system is a pneumatic system. The 6S6M ABS system comprises of a compressor (102), a condensate pump (104), an air dryer (106), a main reservoir, a system protection valve (108), a service brake valve (110), a dual brake valve (112), a modulator valve (114, 118, 120, 122, 124, 126), a brake booster (116).
[0032] The front axles F1, F2 are steerable and all the four axles F1, F2, R1 & R2 are drive axles in the heavy duty vehicle. The internally expandable shoe brake is equipped with S-cam actuation for improved braking. All wheels of the vehicles are provided with service brake. All wheels of the vehicles, except the first front axle (F1) wheels are provided with parking brake (spring applied air released type). All brake actuators used are brake cylinder type (Piston cylinder type) brake boosters (116).
[0033] The F1, F2, R1 and R2 axle wheels are mounted with two pole wheels (LH & RH). Further the pole wheel sensors (202, 204, 206, 208, 210, 212) are mounted F1, R1 and R2 axles. The Anti-lock braking (ABS) system is designed with 6 sensor – 6 modulator (6S6M) configurations for all wheel drive heavy duty vehicle with independent semi float axles as shown in figure 1 and figure 2. Out of 6 modulator valves (114, 118, 120, 122, 124, 126), the brake pressure on all four wheels of the rear axles R1, R2 are directly modulated by 4 modulator valves (120, 122, 124, 126) and the other 2 modulator valves (114, 118) modulate the four wheels of the front axles F1, F2. In other words, one (118) of the two modulator valves is provided to modulate the right hand side (RH) wheels of F1, F2 and other modulator valve (114) is provided to modulate left hand side (LH) wheels of F1 and F2. The RH and LH wheels of F1 and F2 is provided with a pair of modulator valve as front wheel has less load. Out of 6 sensors (202, 204, 206, 208, 210, 212), four sensors (206, 208, 210, 212) are mounted on each wheel of R1 and R2 axles. Two sensors (202, 204) are mounted on the F1 axle wheels.
[0034] Now referring to the flowchart of the figure 4, relates to a method (500) for auto-controlling ABS during differential locking in all wheel drive vehicles comprising the compressor (102) is driven by the engine to generate pressurized air as shown in step 502. At step 504 the air dryer (106) removes the moisture contents and acts like safety valve by maintaining the system pressure. At step 506 the main reservoir stores the compressed air. The system protection valve (108) fitted with inbuilt non return valves ensures system safety and supply air to the service reservoirs at step 508. The service brake valve (110) actuates the brake cylinders after receiving the signal from the dual brake valve (112) and applies the brakes using the air from the service reservoirs at step 510. Then at step 512, the wheel speed sensor (202, 204, 206, 208, 210, 212) senses the wheel rotations and locking conditions to further send the input to the ABS ECU (302). The system then checks the differential / inter axle locking condition at step 514. As per step 516, if the interlocking with disconnection of ABS system while differential / inter axle lock and Off-high way mode of the vehicle operation is not enabled then the ABS ECU (302) regulates and modulates the application of brake and brake pressure to avoid wheel locking with atleast one modulator valve (114, 118, 120, 122, 124, 126). As per step 518, if the interlocking with disconnection of ABS system while differential / inter axle lock and Off-high way mode of the vehicle operation is enabled then the ignition power to the ECU is interrupted through the relay and the ABS ECU (302) is disconnected electrically.
[0035] During the Off high way / cross country driving, when the operator turns the differential locking switch to "ON" (or) engage state, the differential lock switch (Pneumatic) in turn control the pneumatic control cylinder located on the back bone tube structures to engage the differential unit. When the differential unit is engaged, the pneumatic control cylinder provides a signal inside the cabin to indicate the status of differential. When the ABS system is integrated on the vehicle, driving with differential lock engaged condition, an interlock circuit is provided to disconnect the ABS system electrical by using the signal (ground) received from the pneumatic control cylinder. Further, the signal is controlled through the relay to achieve the interlocking of discontinuing of ABS system on the vehicle as shown in figure 4. The block diagram of the ECU and the electrical schematic connection are shown in figure 3.
[0036] The automatic slack adjusters (ASA) are designed to operate by providing a consistent braking performance with minimal wear of the lining and drum. The ASA provides an optimal force to the shoes based on the clearance or the stroke sensing. However for off-road vehicles, the optimal performance of the ASA is not sufficient to give the adequate braking force. For heavy vehicles deployed in mountainous/steep terrain, the gradient is more than 25%, to hold the vehicle from rolling more braking force is required than the normal optimal braking force. In such terrains, the braking stroke needs to be adjusted manually and thus not possible to use an automatic slack adjuster (ASA). Because of this reason ASA is not mandatory in N3 off-road vehicles (N3G) and the ABS system for N3G category of the vehicle in the present invention is equipped with S-Cam Axles and a manual slack adjuster.
[0037] The automatic control of ABS system during differential locking is used in all wheel drive vehicles such as heavy duty vehicles (HDV), a heavy duty trucks (HDT), a semi-trailers, a trailer, a military truck, a tripper, a heavy lorry, a heavy haulers, a heavy good vehicle (HGV), a pickup truck, a military vehicle, all-terrain vehicle and other such vehicles. Further, this present system can also be used in all heavy duty truck with independent semi float axles equipped with S-cam type internally expandable shoe brakes.
[0038] Exemplary embodiments discussed above may provide certain advantages. Though not required to practice aspects of the disclosure, these advantages may include the following.
[0039] Some embodiments of the subject matter enable to provide the system and method for auto-controlling ABS during differential locking in all wheel drive vehicles to prevent wheel locking during excessive braking or panic braking.
[0040] Some embodiments of the subject matter enable to provide the system and method for auto-controlling ABS during differential locking in all wheel drive vehicle to control of ABS during differential lock and off- highway operations.
[0041] Some embodiments of the subject matter enable to provide the system and method for auto-controlling ABS during differential locking in all wheel drive vehicle to maintain the stability of the vehicle.
[0042] Some embodiments of the subject matter enable to the system and method for auto-controlling ABS during differential locking in all wheel drive vehicle when the vehicle is fitted with manual slack adjuster.
[0043] Some embodiments of the subject matter enable to provide the system and method for auto-controlling ABS during differential locking in all wheel drive vehicle which is compact, cost effective and easy to implement.
[0044] Following is a list of elements and reference numerals used to explain various embodiments of the present subject matter.
Reference Numeral Element Description
100 System
102 Air Compressor/ Compressor
104 Condensation Pump
106 Air dryer
108 System Protection Valve
110 Service brake valve
112 Dual brake valve
114 Modulator valve for F1 & F2 LH side
118 Modulator valve for F1 &F2 RH side
120 Modulator valve for R1 LH side
122 Modulator valve for R1 RH side
124 Modulator valve for R2 LH side
126 Modulator valve for R2 RH side
116 Brake booster
202 Wheel Speed Sensor for F1 LH side
204 Wheel Speed Sensor for F1 RH side
206 Wheel Speed Sensor for R1 LH side
208 Wheel Speed Sensor for R1 RH side
210 Wheel Speed Sensor for R2 LH side
212 Wheel Speed Sensor for R2 RH side
302 Controller

Equivalents
[0045] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
[0046] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances, where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."
[0047] Although implementations for the system and method for auto-controlling ABS during differential locking in all wheel drive vehicles have been described in language specific to structural features and/or methods, it is to be understood that the appended claims are not necessarily limited to the specific features described. Rather, the specific features are disclosed as examples of implementation for the system and method for auto-controlling ABS during differential locking in all wheel drive vehicles.
,CLAIMS:
1. A system (100) for auto-controlling ABS during differential locking in all wheel drive vehicles comprising;
atleast one pole wheel assembly with atleast one sensor (202, 204, 206, 208, 210, 212) fixedly mounted on atleast one axle to sense the wheel speed;
a controller (302) configured to receive input signal from said atleast one pole wheel assembly to modulate the brake application by atleast one modulator valve (114, 118, 120, 122, 124, 126);
a differential / inter-axial lock switch provided in the vehicle cabin; and
atleast 6sensor- 6modulator (6S6M) ABS system configured to regulate and modulate the application of brake and brake pressure to avoid wheel locking.

2. The system (100) as claimed in claim 1, wherein said all-wheel drive vehicle is configured to be a 8X8 all-wheel drive heavy duty vehicle (HDV) with independent swing axles and 6Sensor - 6Modulator (6S6M) configuration for anti-lock braking system (ABS).

3. The system (100) as claimed in claim 1, wherein said atleast one pole wheel assembly is provided with atleast one sensor (202, 204, 206, 208, 210, 212) , atleast one sensor holder and atleast one mounting bracket.

4. The system (100) as claimed in claim 1, wherein the controller (302) is configured to be an anti-lock braking system electronic control unit (ABS ECU).

5. The system (100) as claimed in claim 1, wherein the differential / inter-axial lock switch is configured to be a pneumatic type switch.

6. The system (100) as claimed in claim 1, wherein the 6S6M ABS system is a pneumatic system configured with a compressor (102), a condensate pump (104), an air dryer (106), a main reservoir, a system protection valve (108), a service brake valve (110), a dual brake valve (112), atleast one modulator valve (114, 118, 120, 122, 124, 126), a brake booster (116).

7. The system (100) as claimed in claim 1, wherein the 6S6M configuration is configured with four modulator valves (120, 122, 124, 126) provided to modulate brake pressure on each wheel of the rear axles R1, R2 and one modulator valve (114) is provided to modulate brake pressure on left hand (LH) side wheels of the front axle F1, F2 and another modulator valve (118) is provided to modulate brake pressure on right hand (RH) side wheels of the front axle F1, F2.

8. The system (100) as claimed in claim 1, wherein the 6S6M configuration is configured with four sensors (206, 208, 210, 212) mounted on each wheel of the rear axles R1, R2 and two sensors (202, 204) mounted on each wheel of the front axle F1 to sense the wheel speed through magnetic pickup.

9. A method (500) for auto-controlling ABS during differential locking in all wheel drive vehicles comprising the steps of:
operating, a compressor (102) by an engine for generating pressurized air;
removing, the moisture contents through an air dryer (106) and maintaining the system pressure, wherein the air dryer (106) operates as a safety valve;
storing, the compressed air in a main reservoir;
fitting, a system protection valve (108) with inbuilt non return valves for ensuring system safety and supplying air to a service reservoirs;
transmitting, signal from the dual brake valve (112) to the service brake valve (110), wherein the brakes are applied using the air from the service reservoirs;
sensing, the wheel rotations by the wheel speed sensors (202, 204, 206, 208, 210, 212) and locking conditions, wherein the wheel speed sensors (202, 204, 206, 208, 210, 212) sends the signal input to the ABS ECU (302);
A: to regulating and modulating, the application of brake and brake pressure to avoid wheel locking by the ABS ECU (302) with atleast one modulator valve (114, 118, 120, 122, 124, 126) on detection of differential locking disengaged;
or
B: disconnecting the ABS ECU (302) electrically by interrupting the ignition power to the ECU through a relay on detection of differential locking engaged.