Pinpoint Test B : TFT (Transmission Fluid Temperature) Sensor

Pinpoint Tests

PINPOINT TEST B : TFT (Transmission Fluid Temperature) SENSOR

NOTE: If the scan tool is unable to access the transmission PIDs, REFER to Computers and Control Systems Information.

NOTE: Read and record all DTCs.

B1 CHECK THE TFT (Transmission Fluid Temperature) INPUT CIRCUIT

- Ignition OFF.

- Connect the scan tool.

- Disconnect: Transmission C1623.

- Inspect the connector for damaged or pushed out terminals, corrosion, loose wires and missing or damaged seals.

- Ignition ON.

- Access the TFT and TFTV PIDs on the scan tool.

Does the TFT PID display -40°C (-40°F) and the TFTV PID display 4.9 volts?

Yes
GO to B2.

No
REPAIR the vehicle harness circuit VET27 (BN/YE) for a short to ground. CLEAR the DTCs. TEST the system for normal operation.

B2 CHECK THE TFT (Transmission Fluid Temperature) INPUT SIGNAL CIRCUIT FOR VOLTAGE

- Measure the voltage between the transmission vehicle harness C1623-18, circuit VET27 (BN/YE), harness side and ground.





Is the voltage between 3.0 and 5.1 volts?

Yes
GO to B3.

No
INSPECT the vehicle harness circuit VET27 (BN/YE) for an open. If an open circuit is not found, REPLACE the PCM. PROGRAM the PCM with the latest calibration level. PERFORM the solenoid strategy download procedure. REFER to Solenoid Body Strategy Solenoid Body Strategy. TEST the system for normal operation.

B3 CHECK THE TFT (Transmission Fluid Temperature) SIGNAL RETURN CIRCUIT

- Connect a fused jumper between the transmission vehicle harness C1623-18, circuit VET27 (BN/YE) and C1623-19, circuit RE406 (GY/VT), harness side.





Does the TFT PID display a temperature between 195°C-200°C (383°F-292°F) and the TFTV PID display 0 volts?

Yes
GO to B4.

No
INSPECT the vehicle harness circuit RE406 (GY/VT) for an open. If an open circuit is not found, REPLACE the PCM. PROGRAM the PCM with the latest calibration level. PERFORM the solenoid strategy download procedure. REFER to Solenoid Body Strategy Solenoid Body Strategy. TEST the system for normal operation.

B4 CHECK THE TFT (Transmission Fluid Temperature) INTERNAL HARNESS/COMPONENT

- Measure the resistance between the transmission C1623-18, and C1623-19, component side using the following chart.

Transmission Fluid Temperature (TFT)

° C° F Resistance -40 to -20 -40 to -4 967K-284K -19 to -1 -3 to 31 284K-100K 0-20 32-68 100K-37K 21-40 69-104 37K-16K 41-70 105-158 16K-5K 71-90 159-194 5K-2.7K 91-110 195-230 2.7K-1.5K 111-130 231-266 1.5K-0.8K 131-150 267-302 0.8K-0.54K






Does the temperature to resistance specifications match?

Yes
REFER to Diagnosis By Symptom Diagnosis By Symptom to diagnose an overheating concern.

No
INSPECT the transmission internal harness for an open or short to ground. If an open or short to ground is not found, REPLACE the TFT (Transmission Fluid Temperature) sensor.