P016

DTC PO16:

PCM Indicator Circuit:

DESCRIPTION
The Powertrain Control Module (PCM) monitors ignition voltage on CKT 539 to the PCM. This code will set if system voltage drops below 10 volts or goes above 16 volts with the engine running above 500 RPM. If the ignition voltage goes to 0 volt (open circuit) the vehicle will not run since the PCM does not have the ignition signal.

TEST CONDITIONS
RPM 500 or greater.

FAILURE CONDITIONS
Ignition voltage less than 10 volts or greater than 16 volts for 5.3 seconds.

ACTION TAKEN
1. PCM turns "ON" the "SERVICE VEHICLE SOON" Malfunction Indicator Lamp (MIL).
2. PCM disables Evaporative Emission (EVAP) control system.
3. PCM disables cruise control.
4. PCM disables Torque Converter Clutch (TCC) solenoid.
5. PCM disables Exhaust Gas Recirculation (EGR) solenoid.
6. PCM disables long term fuel trim.

NOTES ON FAULT TREE
1. Check PCM Data for parameter PD10. If the voltage is 16 volts or greater is an indication that the generator is not controlling voltage.

2. Checking for proper charging system operation.

3. Checking for proper charging system regulation with no electrical loads on the alternator.

NOTES ON INTERMITTENTS
Code P016 may be stored as a history code if the battery charge was low. Load test the battery and check for proper operation of the charging system.

^ Check for a loose battery cable connection at the starter motor.
^ Check for a loose connection at the generator.