The PCM provides a 5volt reference voltage to the Acceleration Position Sensor1(APS2). The PCM monitors reference voltage deviation from the power supply circuit of the APS2.
PCM sets DTC P0643 if the PCM detects reference voltage higher than threshold value.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Electrical Check | 1. Short to battery in power circuit 2. Poor connection or damaged harness 3. Faulty APS2 |
Enable Conditions |
•
IG "ON" | |
Threshold Value |
•
Short to battery
•
APS2 >5.5V | |
Diagnostic Time |
•
0.1 sec. | |
Mil On Condition |
•
1 driving cycle | |
Limp-Home |
•
Forced limited power mode : The PCM limits opening angle of the throttle valve to max. 50% and engine torque to a certain pre-determined value.
•
After idle recognition, the PCM uses APS1 signal to calculate the current opening angle of the throttle valve. |
