3.3 Electronic Pressure Regulator Solenoids
3.3 Electronic Pressure Regulator Solenoids3.3.1 Description
Six Electronic Pressure Regulator Solenoids are located in the valve block. The solenoids convert the electrical signals into hydraulic control pressure proportional to the signal to actuate the valves for precise transmission operation.
There are six diagnostic checks on each solenoid, a fault it detected if: -
1. Pressure regulator solenoid short circuit to ground. Indicated by an excessive high current when the engine is not running and the solenoid duty cycle is 0% (solenoid not being driven)
2. Pressure regulator solenoid short circuit to ground or open circuit. Indicated by an excessive high current or zero current when the engine is running and the solenoid duty cycle is either 0 % or 100% (solenoid fully off or fully on).
3. Pressure regulator solenoid current too high. Indicated by a high current when the solenoid is driven normally with a solenoid duty cycle between 0 % and 100 %.
4. Pressure regulator solenoid current too low. Indicated by a low current when the solenoid is driven normally with a solenoid duty cycle between 0% and 100 %.
5. Pressure regulator solenoid short circuit to battery positive supply. Indicated by a low current when the engine is not running and the solenoid duty cycle is 0% (solenoid not being driven).
6. Pressure regulator solenoid open circuit. Indicated by a low current when the engine is not running, the solenoid duty cycle is 0% (solenoid not being driven), and a solenoid driver error has been identified.
If the above table does not include details of the following enabling conditions: - IAT, ECT, vehicle speed range, and time after engine start-up then the state of these parameters has no influence upon the execution of the monitor.
Ref. 2 Idrs_high Current versus temperature
Ref. 3 Udrso_prf Solenoid supply voltage versus temperature