Pinpoint Test B: TFT Sensor
PINPOINT TEST B: TFT SENSOR
NOTE: Refer to the Transmission Vehicle Harness Connector illustration in Transmission Connector Layouts Transmission Connector Layouts.
NOTE: Refer to the Transmission Internal Harness Connector illustration in Transmission Connector Layouts Transmission Connector Layouts.
NOTE: Read and record all DTCs.
NOTE: Use the PID Chart for available diagnostic PIDs. Refer to Diagnostic Parameters Identification (PID) Chart TorqShift.
-------------------------------------------------
B1 ELECTRONIC DIAGNOSTICS
- Select PARK.
- Ignition OFF.
- Check to make sure the transmission vehicle harness C1385 is fully seated, terminals are fully engaged in the connector and are in good condition before proceeding.
- Connect the scan tool.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: PID List.
- Monitor the appropriate PID for the Transmission Fluid Temperature (TFT) sensor.
- Can the PIDs be monitored?
Yes
GO to B2.
No
REPEAT procedure to enter PID list. If the vehicle did not enter PID list, REFER to Computers and Control Systems Information for diagnosis of the PCM.
-------------------------------------------------
B2 WARM-UP/COOL-DOWN CYCLE
- While monitoring the TFT PIDs, carry out the following test: If transmission is cold, operate to warm it up. If transmission is warm, allow transmission to cool down.
- Does the TFT PIDs temperature increase as the transmission is warmed up or decrease as the transmission is cooled or does the TFT drop in and out of range?
Yes
CLEAR the DTCs. CARRY OUT the road test to verify if concern is still present. 5: Road Test If concern is still present, REFER to Diagnosis By Symptom Diagnosis By Symptom to diagnose transmission overheating.
No
GO to B3.
-------------------------------------------------
B3 ELECTRICAL SIGNAL CHECK
- Disconnect: Transmission Vehicle Harness C1385.
- Visually inspect all wires and connector for damage.
- Measure the voltage between the transmission vehicle harness C1385-18, harness side and ground.
- Is the voltage between 4.5 and 5.5 volts?
Yes
GO to B4.
No
REPAIR an open or short in the transmission vehicle harness. CLEAR the DTCs. TEST the system for normal operation. If normal operation does not return, INSTALL a new PCM.
-------------------------------------------------
B4 CHECK THE RESISTANCE OF THE TFT SENSOR
- Measure the resistance between the transmission internal harness C1385-18 and C1385-22, component side.
- Record the resistance.
- Resistance should be approximately in the following ranges using the following chart.
TRANSMISSION FLUID TEMPERATURE (TFT):
- Is the resistance in range?
Yes
REFER to Diagnosis By Symptom Diagnosis By Symptom to diagnose an overheating concern.
No
GO to B5.
-------------------------------------------------
B5 CHECK THE INTERNAL HARNESS FOR AN OPEN
- Drain the transmission fluid.
- Remove the transmission fluid pan.
- Disconnect: TFT Sensor.
- Measure the resistance between the transmission internal harness and C1385-22 and the TFT sensor connector using the following chart.
- Are the resistances less than 5 ohms?
Yes
GO to B6.
No
INSTALL a new internal harness. CLEAR the DTCs. TEST the system for normal operation.
-------------------------------------------------
B6 CHECK THE INTERNAL HARNESS FOR A SHORT TO GROUND
- Measure the resistance between transmission internal harness C1385 and ground using the following chart.
- Is the resistance greater than 10,000 ohms?
Yes
GO to B7.
No
INSTALL a new internal harness. CLEAR the DTCs. TEST the system for normal operation.
-------------------------------------------------
B7 CHECK THE RESISTANCE AT THE SENSOR
- Measure the resistance between pins 1 and 2 at the TFT sensor.
TRANSMISSION FLUID TEMPERATURE (TFT):
- Is the resistance within specification?
Yes
CLEAR the DTCs. If the DTCs return and an overtemp condition is present, REFER to Computers and Control Systems Information. If the condition returns, INSTALL a new PCM.
No
INSTALL a new TFT sensor. CLEAR the DTCs. TEST the system for normal operation.
-------------------------------------------------