Test Z: The Engine Over Temperature Reconfigurable Telltale Indicator Is Never/Always On

PINPOINT TEST Z: THE ENGINE OVER TEMPERATURE RECONFIGURABLE TELLTALE INDICATOR IS NEVER/ALWAYS ON

Normal Operation
There are 3 separate situations when the instrument cluster (IC) receives a message to turn on the engine over temperature reconfigurable telltale indicator; a high engine temperature condition, failsafe cooling 1 or failsafe cooling 2 state. The PCM sends the applicable message to the instrument cluster (IC) over the high speed controller area network (HS-CAN) communication bus whenever any of the 3 conditions exist. The PCM receives the engine coolant temperature status through hardwired circuitry to the cylinder head temperature (CHT) sensor. If a high engine temperature condition exists, the PCM sends a message to the instrument cluster (IC) to turn on the engine over temperature reconfigurable telltale indicator. If a failsafe warning condition exists, the PCM sends a message to the instrument cluster (IC) to flash the engine over temperature reconfigurable telltale indicator.

If the instrument cluster (IC) does not receive the engine temperature or failsafe cooling status or if the data is deemed invalid by the instrument cluster (IC) for more than 5 seconds, the message is considered missing and the instrument cluster (IC) sets DTC U0100 and defaults the temperature gauge to the cold (C) stop and the engine over temperature reconfigurable indicator on.

- DTC U2199 (Invalid Engine Coolant Temperature Data) - is a continuous DTC that sets if the instrument cluster (IC) receives invalid engine temperature data from the PCM. The instrument cluster (IC) defaults the temperature gauge to the cold (C) stop and turns on the engine over temperature reconfigurable telltale.

This pinpoint test is intended to diagnose the following:
- PCM
- Instrument cluster (IC)

Z1-Z3:

Z4-Z5: