Pinpoint Test B: Transmission Fluid Temperature (TFT) Sensor
WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Refer to Figure preceding these pinpoint tests.
- B1 ELECTRONIC DIAGNOSTICS
- Key in OFF position.
- Select PARK.
- Check to make sure the transmission harness connector is fully seated, terminals are fully engaged in connector and in good condition before proceeding.
- Connect the scan tool.
- Key in ON position.
- Enter the following diagnostic mode on the scan tool: Diagnostic Data Link.
- Enter the following diagnostic mode on the scan tool: PCM.
- Enter the following diagnostic mode on the scan tool: PID/Data Monitor and Record.
- Enter the following diagnostic mode on the scan tool: PIDs; TFT, TFTV.
- Does the vehicle enter PID/Data Monitor and Record?
- Yes : REMAIN in PID/Data Control. GO to B2.
- No : REPEAT procedure to enter PID. If vehicle did not enter PID, See INTRODUCTION - GASOLINE article for diagnosis of PCM and NGS.
- B2 WARM-UP/COOL-DOWN CYCLE
- While monitoring the TFT PIDs, carry out the following test: If transmission is cold, run transmission to warm it up. If transmission is warm, allow transmission to cool down.
- Do the TFT PIDs increase as the transmission is warmed up or decrease as the transmission is cooled or does the TFT or TFTV drop in and out of range?
- Yes
: If the TFT PIDs increase as the transmission is warmed or decrease as the transmission is cooled, CLEAR all DTCs. ROAD TEST to verify if concern is still present. If concern is still present, REFER to DIAGNOSIS BY SYMPTOM to diagnose transmission overheating.
If the TFT or TFTV drop in and out of range, INSPECT for intermittent concern in the internal/external harness, sensor or connector.
- No : GO to B3.
- B3 ELECTRICAL SIGNAL CHECK
- Disconnect: Transmission Harness Connector.
- Visually inspect all wires and connectors for damage.
- Measure the voltage between pin 2 harness side and ground.
- Is the voltage between 4.5 and 5.5 volts?
- Yes : GO to B4.
- No : REPAIR the circuit. TEST the system for normal operation.
- B4 CHECK RESISTANCE OF THE TFT SENSOR
- Measure the resistance between pin 2 and 12 at the solenoid body connector.
- Record the resistance.
- Resistance should be approximately in the following ranges:TRANSMISSION FLUID TEMPERATURE SENSOR RESISTANCE
°C °F Resistance (Ohms) -40 to -20 -40 to -4 967K - 284K -19 to -1 -3 - 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 - Is the resistance within range?
- Yes : REFER to DIAGNOSIS BY SYMPTOM to diagnose an overheating concern.
- No : INSTALL a new solenoid body assembly.