Pinpoint Test C: The Temperature Gauge Is Inoperative

Instrumentation and Warning Chimes

Pinpoint Test C: The Temperature Gauge Is Inoperative

Normal Operation

The PCM uses the Cylinder Head Temperature (CHT) sensor to measure the engine temperature. The Instrument Cluster (IC) receives the engine temperature data from the PCM over the High Speed Controller Area Network (HS-CAN) communication bus. The IC (Instrument Cluster) monitors the engine temperature data received from the PCM and commands the temperature gauge indication with a corresponding movement of the pointer.

If the engine temperature data is missing or invalid for 5 seconds or less, the IC (Instrument Cluster) defaults the temperature gauge to the last setting, based upon the last known good temperature status message. If the IC (Instrument Cluster) does not receive the engine temperature status message from the PCM for more than 5 seconds, the IC (Instrument Cluster) sets DTC U0100 in continuous memory and defaults the temperature gauge to cold (C). If the engine temperature status message is invalid for more than 5 seconds, the IC (Instrument Cluster) sets DTC U2199 in continuous memory and defaults the temperature gauge to cold (C).

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

This pinpoint test is intended to diagnose the following:

- PCM

- IC (Instrument Cluster)

PINPOINT TEST C : THE TEMPERATURE GAUGE IS INOPERATIVE

C1 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO (Key ON Engine OFF) SELF-TEST

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

Are any DTCs recorded?

Yes
REFER to the Computers and Control Systems Information.

No
GO to C2.

C2 RETRIEVE THE RECORDED DTCs FROM THE IC (Instrument Cluster) SELF-TEST

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

Are any DTCs recorded?

Yes
For DTC U0100, GO to Pinpoint Test AJ. Pinpoint Test AJ: DTC U0100

For all other DTCs, REFER to DTC Charts. Instrument Panel, Gauges and Warning Indicators

No
GO to C3.

C3 CARRY OUT THE TEMPERATURE GAUGE ACTIVE COMMAND USING THE SCAN TOOL

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: IC (Instrument Cluster) DataLogger.

- NOTE: The coolant temperature should range between [-]40-59°C (40-138°F) with the gauge in the cold (C) range, between 60-120°C (140-248°F) with the gauge in the normal or mid-range and above 121-123°C (250-253°F) with the gauge in the hot (H) range.

Select the IC (Instrument Cluster) temperature gauge (ENGCOOLNT) active command. Command the temperature gauge to the approximate values in the following table while monitoring the gauge.

Temperature Command Gauge Position Below 50°C (122°F) Cold (C) Approximately 87°C (189°F) Center of the gauge (mid-range) Above 121°C (250°F) Full hot (H)

Does the temperature gauge operate according to the above specifications?

Yes
INSTALL a new PCM. TEST the system for normal operation.

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