Circuit Description
The powertrain control module (PCM) monitors the system voltage on the ignition feed terminals to the PCM. A system voltage DTC sets whenever the voltage is above a specified calibrated value.
Conditions For Setting The DTC
The system voltage is more than 17 volts.
Action Taken When the DTC Sets
| • | The PCM records the operating conditions at the time the diagnostic fails. The Failure Records buffers stores this information. |
| • | A history DTC is stored. |
Conditions for Clearing the DTC
| • | A history DTC clears after 40 consecutive warm up cycles without a fault. |
| • | Use a scan tool to clear the DTCs. |
Diagnostic Aids
| • | Charging the battery with a battery charger and starting the engine can cause a DTC to set. |
| • | If the DTC sets when you operate an accessory, inspect for a poor connection or an excessive current draw. |
| • | Additional DTCs can set as the result of the PCM disabling the outputs. |
Test Description
The numbers below refers to the step numbers on the diagnostic table:
-
The replacement PCM must be programmed and the Crankshaft Position System Variation Learn procedure must be performed.
-
If no malfunctions are present at this point and no additional DTCs were set. Refer to Diagnostic Aids for additional checks and information.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 |
Does the ignition voltage read more than the specified value? | 1,400 RPM 17 V | Go to Diagnostic Aids | |
3 | Measure the battery voltage at the battery while running the engine at the specified value using a DMM. Does the battery voltage read less than the specified value? | 2,000 RPM 17 V | Go to Powertrain Control Module Controlled Generator Diagnosis | |
|
Important:: The replacement PCM must be programmed.
Did you complete the replacement? | -- | -- | ||
5 |
Does the DTC reset? | -- | System OK |
