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Pinpoint Test 6: Incorrect Speedometer Indication




PINPOINT TEST 6: INCORRECT SPEEDOMETER INDICATION

Normal Operation

The instrument cluster receives the vehicle speed sensor (VSS) signal from the PCM over the high speed controller area network (HS-CAN) communication bus. The instrument cluster monitors the VSS input from the PCM and commands the speedometer with a corresponding movement of the pointer.If the instrument cluster receives invalid vehicle speed data from the PCM for 5 seconds or less, the instrument cluster defaults the speedometer to the last setting, based upon the last known good vehicle speed message. If the instrument cluster does not receive the vehicle speed data from the PCM or if the data received is deemed invalid, the instrument cluster sets DTC U0100 in continuous memory and defaults the speedometer to 0 km/h (0 mph).
NOTE:If DTC U0100 is set in the instrument cluster, other observable symptoms may be an inoperative tachometer, temperature gauge or odometer.

Possible Causes
- Axle ratio configuration
- Tire size configuration
- PCM
- Instrument cluster

Diagnostic Procedure