Test Dd: Fuel Tank Temperature Sensor: Testing

WARNING: This page is about a different car, the 2002 Ford Pickup and 2002 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

1) Check FTT Sensor Connector

Turn ignition off. Check FTT sensor harness connector for damage and good connection. FTT sensor is located on fuel tank. If FTT sensor harness connector is okay, go to next step. If FTT sensor harness connector is faulty, repair or replace connector as necessary, then go to step 3).

NOTE: A non-functioning FTT sensor will give a constant reading of 59°F (15°C) if circuit is still intact.

2) Check FTTMP PID Default
Ensure ignition is off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, access AFCM and select FTTMP PID from PID/DATA MONITOR & RECORD menu. If FTTMP is not defaulted to 59°F (15°C), leave scan connected and go to next step. If FTTMP PID is defaulted to 59°F (15°C), replace FTT sensor.

3) Check FTTMP PID

Connect scan tool to DLC if not done previously. Turn ignition on. Using scan tool, access AFCM and select FTTMP PID from PID/DATA MONITOR & RECORD menu. If FTTMP PID value is more than -58°F (-50°C) and less than 140°F (60°C), system is operating normally, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES - EEC-V - BI-FUEL article. If FTTMP PID value is less than -40°F (-40°C), leave scan tool connected and go to next step. If FTTMP PID value is more than 248°F (120°C), leave scan tool connected and go to step 5).

4) Check FTT Circuit For Short

Turn ignition on. Using scan tool, access FTTMP PID from PID/DATA MONITOR & RECORD menu. Disconnect FTT sensor connector. If FTTMP PID value is about 140°F (60°C), replace FTT sensor. If FTTMP PID value is not about 140°F (60°C), go to step 6).

5) Check FTT Circuit For Open

Turn ignition on. Using scan tool, access FTTMP PID from PID/DATA MONITOR & RECORD menu. Disconnect FTT sensor connector. Connect a jumper wire between FTT sensor harness connector terminals. If FTTMP PID value is about -58°F (-50°C) or is more than 140°F (60°C), replace FTT sensor. If FTTMP PID value is not about -58°F (-50°C) or is 140°F (60°C) or less, remove jumper wire and go to next step.

CAUTION: Always disconnect bi-fuel relay module power supply 3-pin harness connector C495 before disconnecting or reconnecting compuvalve main harness connector C1294 to avoid damaging compuvalve or connectors. See Figure.

6) Check FTT Circuit To Compuvalve For Open
Turn ignition off. Ensure FTT sensor is disconnected. Disconnect bi-fuel relay module power supply harness connector C495. Disconnect compuvalve harness connector C1294. Using DVOM, measure resistance between compuvalve harness connector C1294 terminal No. 8 (White wire) and FTT sensor terminal "A" (Black wire). Also. measure resistance between compuvalve harness connector C1294 terminal No. 26 (White wire) and FTT sensor terminal "B" (Orange wire). See Figure and Figure . If both resistances are less than 5 ohms, perform COMPUVALVE CHECK under QUICK TEST. If fault still exists, replace compuvalve. If either resistance is 5 ohms or more, repair open in affected circuit between FTT sensor and compuvalve. See WIRING DIAGRAMS article.