DTC 53

Chart - Code 53 System Over Voltage:

Wiring Diagram for System Over Voltage:

CIRCUIT DESCRIPTION
Code 53 will set when the ignition is "ON" and the engine RPM is greater than 800 and the Electronic Control Module (ECM) is seeing a ignition fuel reference voltage of more than 16.9 volts for more than 10 seconds. During the time the failure is present, all ECM outputs will be disengaged. (The setting of additional codes may result).

TEST DESCRIPTION
Numbers below refer to circled numbers on the diagnostic chart.

1. Normal battery output is between 10 - 16.9 volts.
2. Checks to see if the high voltage reading is due to the generator or ECM. With engine running, check voltage at the battery. If the voltage is above 12.1 volts, the ECM is OK.
3. Checks to see if generator is faulty under load condition. If the voltage is above 17.1 volts, repair Alternator.