NGC

P2610-PCM INTERNAL SHUTDOWN TIMER FAST RATIONALITY





For a complete wiring diagram Consult Diagrams/Electrical

Theory of Operation

The PCM compares actual shutdown time to a calculated shutdown time value. The calculated shut down time value is based on the amount of shutdown time necessary for the ECT to drop a specific amount after a completely warmed up engine is shut down. If the difference between actual shutdown time and the calculated shut down time is greater than a maximum value, a one trip failure will set. The shutdown time is measured again after 1 hour of ignition off time following the next engine warm up cycle. The PCM compares the shutdown time to a calculated value. If the difference is greater than a maximum value, the MIL is illuminated and a DTC will set.

- When Monitored:
With the engine running after a cycle when a complete engine warm up was achieved, the difference between engine coolant temperature and ambient air temperature greater than 10° C (50° F), after a minimum temperature drop of 10° C (50° F) during ignition off, and battery voltage greater than 10 volts.

- Set Condition:
The PCM detects that the engine coolant temperature does not drop a specified amount during the measured engine off time. Two trip fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE

NOTE: Diagnose and repair any other DTCs set in the PCM before proceeding with this test.

Turn the ignition on.
With the scan tool, Clear DTCs in the Powertrain Control Module (PCM).
Start the engine and allow it to reach operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

2. CHECKING THE PCM POWER AND GROUND CIRCUITS
Perform the diagnostic procedure for *CHECKING THE PCM POWER AND GROUND CIRCUITS. Checking the PCM Power and Ground Circuits
Were any problems found?

Yes

- Repair the PCM power and ground circuit(s) as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 3

3. POWERTRAIN CONTROL MODULE (PCM)
Verify that the PCM is operating at the latest software version available.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test.Powertrain Verification Test