PCM/ECM sets DTC P0642 if the PCM/ECM detects reference voltage is lower than threshold value.
Item | Detecting Condition | Possible Cause | |
Case 1 | DTC Strategy |
•
Electrical check | 1. Short to ground in power circuit 2. Poor connection or damaged harness 3. Faulty APS2 |
Enable Conditions |
•
IG "ON" | ||
Threshold Value |
•
Short to ground
•
APS power supply voltage_2 < 0.7 V | ||
Case 2 | DTC Strategy |
•
Electrical check | |
Enable Conditions |
•
IG ON | ||
Threshold Value |
•
Sensor or wiring harness problem
•
0.7 V ≤ APS power supply voltage_2 < 4.5 V | ||
Diagnostic Time |
•
0.1 sec. | ||
Mil On Condition |
•
1 driving cycle | ||
Limp-Home |
•
Forced limited power mode : The PCM/ECM limits opening angle of the throttle valve to max. 50% and engine torque to a certain pre-determined value.
•
After idle recognition, the PCM/ECM uses APS1 signal to calculate the current opening angle of the throttle valve. | ||
