Description:Complete Specification

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to a method to detect starter motor degeneration, and more specifically to the method for detecting starter motor degeneration using battery voltage.

Background of the invention
[0002] DE 2230147 B2 describes a light control circuit for center tapped battery and has load divided alternately over battery halves with starter motor powered by both. The vehicle lighting circuit is divided in load between the two batteries which are connected in series to drive the starter motor. A center tapping is taken from the batteries to a relay-controlled circuit which switches half the load alternately to each battery. The relay switching can be initiated each time the lights are switched on. They can be on a time base, operated by a multivibrator. The system eliminated unequal drain, and hence increased degeneration of the battery, if the loading is unequal. This can occur if a lamp is replaced, with the new lamp having lower resistance filaments, when unaged.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates an algorithm to detect starter motor degeneration using battery voltage.

Detailed description of the embodiments
[0004] Figure 1 illustrates a method 100 for detecting starter motor degeneration using battery voltage. The method 100 comprises monitoring 110 a voltage of a battery during vehicle cranking, evaluating 120 a region of a battery voltage dip during engine cranking, determining 130 if the region of the battery voltage dip is below a threshold limit that is pre-determined by a user, and determining 140 that the starter motor has degenerated and is required to be replaced if the region of the battery voltage dip is below the threshold limit that is pre-determined by the user. The method 100 further comprises determining 150 that the starter motor has degenerated and is required to be replaced if an engine coolant temperature is below a threshold temperature, an engine speed is below a threshold speed, and a vehicle accelerator position is below a threshold accelerator position.

[0005] Figure 1 illustrates a method 100 for detecting starter motor degeneration using battery voltage. The method 100 comprises monitoring 110 a voltage of a battery during vehicle cranking. More specifically, the electronic control unit monitors the voltage of the vehicle during cranking of the vehicle to determine if the voltage supplied to the starter motor is within its acceptable operating temperature range. Once the electronic control unit monitors the voltage of the vehicle during cranking of the vehicle, the electronic control unit evaluates 120 a region of a battery voltage dip during engine cranking. From the battery voltage dip, it is determined 130 if the region of the battery voltage dip is below a threshold limit that is pre-determined by a user. Thereafter, the electronic control unit determines 140 that the starter motor has degenerated and is required to be replaced if the region of the battery voltage dip is below the threshold limit that is pre-determined by the user.

[0006] In an exemplary embodiment, the method 100 further comprises determining 150 that the starter motor has degenerated and is required to be replaced if an engine coolant temperature is below a threshold temperature. In addition, the method 100 further comprises determining 160 that the starter motor has degenerated and is required to be replaced if an engine speed is below a threshold speed. Furthermore, the method 100 comprises determining 170 that the starter motor has degenerated and is required to be replaced if a vehicle accelerator position is below a threshold accelerator position.

[0007] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.
, Claims:We Claim

1. A method (100) for detecting starter motor degeneration using battery voltage, the method (100) comprising:
monitoring (110) a voltage of a battery during vehicle cranking;
evaluating (120) a region of a battery voltage dip during engine cranking;
determining (130) if the region of the battery voltage dip is below a threshold limit that is pre-determined by a user; and
determining (140) that the starter motor has degenerated and is required to be replaced if the region of the battery voltage dip is below the threshold limit that is pre-determined by the user.

2. The method (100) for detecting starter motor degeneration using battery voltage in accordance with Claim 1, wherein it is determined (150) that the starter motor has degenerated and is required to be replaced if an engine coolant temperature is below a threshold temperature.

3. The method (100) for detecting starter motor degeneration using battery voltage in accordance with Claim 1, wherein it is determined (160) that the starter motor has degenerated and is required to be replaced if an engine speed is below a threshold speed.

4. The method (100) for detecting starter motor degeneration using battery voltage in accordance with Claim 1, wherein it is determined (170) that the starter motor has degenerated and is required to be replaced if a vehicle accelerator position is below a threshold accelerator position.