Pinpoint Test AB: The Engine Over-Temperature Message Center Warning Indicator Is Never/Always On

Instrumentation, Message Center and Warning Chimes

Pinpoint Test AB: The Engine Over-Temperature Message Center Warning Indicator Is Never/Always On

Normal Operation

The Instrument Panel Cluster (IPC) receives the engine over-temperature command from the PCM over the High Speed Controller Area Network (HS-CAN) communication bus. If the PCM detects an engine over-temperature condition or has entered into the fail-safe cooling mode, the PCM sends a command to the IPC (Instrument Panel Cluster) to turn the engine over-temperature warning indicator on. The PCM provides a fail-safe cooling strategy that begins limiting engine performance and provides engine shut down in the event that the engine has reached an over-temperature condition.

If the engine over-temperature message is missing or invalid for less than 5 seconds, the engine over-temperature message center warning indicator remains in the last state (on or off) based upon the last known good message received. If the engine over-temperature message is missing for more than 5 seconds, the IPC (Instrument Panel Cluster) sets DTC U0100:00 in continuous memory and defaults the engine over-temperature message center warning indicator on.

NOTE: If DTC U0100:00 is set in the IPC (Instrument Panel Cluster), other observable symptoms may be an inoperative speedometer, tachometer or odometer.

This pinpoint test is intended to diagnose the following:

- PCM concern

- IPC (Instrument Panel Cluster)

PINPOINT TEST AB : THE ENGINE OVER-TEMPERATURE MESSAGE CENTER WARNING INDICATOR IS NEVER/ALWAYS ON

AB1 CHECK THE MESSAGE CENTER WARNING INDICATOR FUNCTION

- Close all doors, hood and luggage compartment lid.

- Ignition ON.

- Open the driver door while monitoring the door ajar message center displays.

Does the door ajar message center warning indicator display?

Yes
GO to AB2.

No
INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.

AB2 RETRIEVE THE RECORDED DTCs FROM PCM KOEO (Key ON Engine OFF) SELF-TEST

- Check for recorded PCM DTCs from the Key ON Engine OFF (KOEO) self-test.

Are any PCM DTCs recorded?

Yes
REFER to Computers and Control Systems Information.

No
GO to AB3.

AB3 RETRIEVE THE RECORDED DTCs FROM THE IPC (Instrument Panel Cluster) SELF-TEST

- Check for recorded DTCs from the IPC (Instrument Panel Cluster) self-test.

Is DTC U0100:00 recorded?

Yes
GO to Pinpoint Test AQ.

No
If the engine over-temperature message center warning indicator is never on, the system is functioning normally.

If the engine over-temperature message center warning indicator is always on, INSTALL a new PCM. TEST the system for normal operation.