Powertrain Controls - ECM/PCM

Code 62 Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION:

The engine oil temperature sensor uses a thermistor to control the signal voltage to the ECM. The ECM applies voltage (about 5 volts) on circuit 1313. When the engine is cold, the sensor resistance is high, therefore, the ECM will see a low voltage. The engine oil temperature sensor is not used by the ECM to determine any calibration values. This sensor information is processed in the ECM and sent across serial data, on circuit 800, to the Central Control Module (CCM) for use in determining when to change the engine oil.

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

1. Code 52 will set if:

^ Time since engine start is 30 minutes.
^ Signal voltage indicates engine oil temperature below 144~C (291~F).


DIAGNOSTIC AIDS:

^ If code 62 was set; the CCM's oil life monitor system has been calculating the engine oil life with false information. The oil life monitor must be reset and the engine oil and filter may be changed.

^ A Scan tool reads temperature of the oil in the engine and should read close to ambient air temperature on a cold engine and rise as engine oil temperature increases.

^ Check harness routing for possible short to ground in CKT 13133.

^ Refer to TESTING PROCEDURES/DIAGNOSIS BY SYMPTOM/INTERMITTENTS..