Test D: Inaccurate Speedometer Reading

PINPOINT TEST D: INACCURATE SPEEDOMETER READING

D1-D4:

Normal Operation
The speedometer is controlled by a signal sent from the powertrain control module (PCM) to the instrument cluster through circuit 679 (GY/BK). The instrument cluster interprets the signal sent from the PCM and commands the speedometer to sweep to the correct reading.

Possible Causes
- incorrect tire size
- PCM
- instrument cluster