Diagnostic Instructions
Circuit/System Description
The instrument panel cluster (IPC) supplies current to the automatic transmission fluid temperature sensor and measures the voltage drop in the circuit. When the transmission fluid is cold, the sensor resistance is high and the IPC detects a high signal
voltage. As the fluid temperature warms to a normal operating temperature, the resistance becomes less and the signal voltage decreases. The IPC uses this information to determine the temperature value for the transmission temperature gage.
Reference Information
Schematic Reference
Driver Information System Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Instrument Cluster Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the automatic transmission fluid temperature sensor.
- Ignition OFF, test for less than 1 ohm between the ground circuit terminal B and ground
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify the scan tool Trans. Fluid Temp. parameter is less than 40°C (104°F).
⇒ | If greater than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the transmission fluid temperature gage. |
- Install a 3-amp fused jumper between the signal circuit terminal A and ground. Verify the scan tool Trans. Fluid Temp. parameter is greater than 120°C (248°F).
⇒ | If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the transmission fluid temperature gage. |
- If all circuits test normal, replace the automatic transmission fluid temperature sensor.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.