Circuit/System Testing
WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Disconnect the AT 20-way inline connector. Using a DMM and the J 35616
GM-approved terminal test kit, measure the voltage at the TFT sensor signal circuit at the engine side of the connector. The voltage should be 4.9-5.1 volts.
- If the voltage is less than the specified range, test the TFT sensor signal circuit for an open, high resistance, or short to ground.
IMPORTANT: If a short to voltage is found, test the TFT sensor for damage.- If the voltage is above the specified range, test the TFT sensor signal circuit for a short to voltage.
- Using the J 35616
, measure the voltage between the TFT sensor signal circuit and the low reference circuit at the engine side of the AT 20-way inline connector. The voltage should be 4.9-5.1 volts.
- If the voltage is less than the specified value, test the low reference circuit for an open, high resistance, or short to ground.
- Install the J 44152
jumper harness (20 Pins) on the transmission side of the AT 20-way inline connector. See Special Tools
. Using the J 35616
, measure the resistance between the TFT sensor signal circuit and the low reference circuit. Refer to Temperature Versus Resistance
.
- If the resistance is greater than the specified range for a given temperature, test the TFT sensor signal circuit and the low reference circuit for an open or high resistance.
- If the resistance is less than the specified range, test the TFT sensor signal circuit and the low reference for a shorted together condition or a faulty TFT sensor.
- If a shorted together condition is found, replace the transmission wiring harness.
- Using the J 35616
, measure the resistance between the TFT sensor signal circuit and the transmission case. The resistance should be greater than 10K ohms.
- If the resistance is less than 10K ohms, test the TFT sensor signal circuit for a short to the transmission case.
- If a short to the case is found, replace the transmission wiring harness.
- Using the J 35616
, measure the resistance between the low reference circuit and the transmission case. The resistance should be greater than 10K ohms.
- If the resistance is less than 10K ohms, test the low reference circuit for a short to the transmission case.
- If a short to the case is found, replace the transmission wiring harness.
- Using the J 35616
, measure the resistance between the TFT sensor signal circuit and all other circuits of the J 44152
except the low reference circuit. See Special Tools
. The resistance should be greater than 10K ohms.
- If the resistance is less than 10K ohms, replace the transmission wiring harness.
- If all circuits/connections test normal, test the TFT sensor.