Component Testing
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
- Disconnect the automatic transmission 20-way inline connector and measure the resistance between the TFT sensor signal circuit and the low reference circuit. Refer to Temperature Versus Resistance - Engine Coolant Temperature Sensor
and Temperature Versus Resistance - Intake Air Temperature Sensor
for the 3.6L engine or Temperature Versus Resistance
for the 3.8L engine or Temperature Versus Resistance
for the 5.3L engine for resistance values.
- If the resistance is not within the specified range for the given temperature, replace the TFT sensor.
- Test the TCM for supplying the 5-volt reference circuit to the TFT sensor.
- If the TCM is not supplying a 5-volt reference to the TFT sensor, replace the TCM.