Higher Than Normal Engine Coolant Temperature Gauge Readings (Reprogram PCM)

Some customers may comment on higher than normal engine coolant temperature gauge readings when operating the vehicle in very high outside ambient temperatures, and in stop and go or slow moving traffic.

Reduced air flow across the radiator and preheated air from stopped or slow moving driving conditions from traffic congestion may result in normally higher engine coolant operating temperatures as indicated by the temperature gauge.

Technicians are to reprogram the PCM with an updated software calibration. This new service calibration was released with TIS satellite data update version 7.3 available July 7, 2004. As always, make sure your TECH 2® is updated with the latest software version.

This new calibration will cause the PCM to command small amounts of additional fan engagement to control engine coolant temperatures and gauge readings closer to a customer perception of normal.

For vehicles repaired under warranty, use:

* This is a unique labor operation number for use only with this bulletin. This number will not be published in the Labor Time Guide.