Fuel Temperature Sensor, Checking
- Fuel system is under pressure.
Use only gold-plated terminals when servicing terminals in the electrical harness connector of Fuel Temperature Sensor -G81-.
Special tools and workshop equipment required
- Multimeter.
- jumper wire.
- Wiring diagram.
Test requirements
- The Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- fuses OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, shift selector lever into position "P" or "N".
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.
- Engine cold.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to GENERAL DIAGNOSIS .
Start diagnosis
-- Perform the function test in diagnostic mode 06. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .
If the specified values were not obtained:
Checking internal resistance
-- Disconnect the Fuel Temperature Sensor -G81- electrical harness connector -arrow-.
-- Using a multimeter, check the Fuel Temperature Sensor -G81- terminals 1 to 2 for resistance.
Use the chart below for the specified values:
- Area A: Resistance values 0 to 50° C (32° - 122° F).
- Area B: Resistance values 50 to 100° C (122° - 212° F).
Examples:
- Range A, 30° C (86° F) equals a resistance of 1500 to 2000 Ω
- Range B, 80° C (176° F) equals a resistance of 275 to 375Ω
If any of the specified values were not obtained:
-- Replace the Fuel Temperature Sensor -G81-.
If the specified values were obtained:
Checking wiring
If the manufacturers test box is being used, perform the following step.
-- Install the test box. Refer to 68-PIN TEST BOX ADAPTER, VAG1598/19, INSTALLING .
If the manufacturers test box is not being used, perform the following step.
-- Remove the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248-. Refer to DIESEL DIRECT FUEL INJECTION ECM, REPLACING .
-- Using a Multimeter --, check the Fuel Temperature Sensor -G81- electrical harness connector terminals to the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- electrical harness connector T60 terminals for resistance.
| Fuel Temperature Sensor -G81- electrical harness connector terminals | Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- electrical harness connector T60 terminals or test box socket |
|---|---|
| 1 | 40 |
| 2 | 39 |
Specified value: 1.5 Ω Max.
If the specification was not obtained:
-- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
-- If necessary, repair the faulty wiring connection.
If no malfunction is detected in the wiring:
-- Replace the Fuel Temperature Sensor -G81-.
-- Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
-- Perform a road test to verify repair.
If the DTC does not return:
Repair complete, Generate readiness code. Refer to READINESS CODE .
-- End diagnosis.
If the DTC does return and no malfunction is detected in the wiring:
-- Replace the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248-. Refer to DIESEL DIRECT FUEL INJECTION ECM, REPLACING .
-- Assembly is performed in the reverse of the removal.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test requirements
- The Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- fuses OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, shift selector lever into position "P" or "N".
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to GENERAL DIAGNOSIS .
Start diagnosis
-- Perform the function test in diagnostic mode 06. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .
If the specified value was not obtained:
-- Disconnect the Diesel Fuel Injection Pump -- electrical harness connector.
Checking internal resistance
-- Using a multimeter, check the Diesel Fuel Injection Pump -- terminals 4 to 7 for resistance.
Use the chart below for the specified values:
- Area A: Resistance values 0 to 50° C (32° - 122° F).
- Area B: Resistance values 50 to 100° C (122° - 212° F).
Examples:
- Range A, 30° C (86° F) equals a resistance of 1500 to 2000 Ω
- Range B, 80° C (176° F) equals a resistance of 275 to 375Ω
If any of the specified values are not obtained:
-- Replace the Diesel Fuel Injection Pump --.
If the specified values were obtained:
Checking wiring
If the manufacturers test box is being used, perform the following step.
-- Install the test box. Refer to 68-PIN TEST BOX ADAPTER, VAG1598/19, INSTALLING .
If the manufacturers test box is not being used, perform the following step.
-- Remove the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248-. Refer to DIESEL DIRECT FUEL INJECTION ECM, REPLACING .
-- Using a Multimeter --, check the Diesel Fuel Injection Pump -- electrical harness connector terminals to the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- electrical harness connector T121 terminals for resistance.
| Diesel Fuel Injection Pump -- electrical harness connector T10 terminals | Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- electrical harness connector T121 terminals or test box socket |
|---|---|
| 4 | 103 |
| 7 | 111 |
Specified value: 1.5 Ω Max.
If the specification was not obtained:
-- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
-- If necessary, repair the faulty wiring connection.
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
If no malfunction is detected in the wiring:
-- Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
-- Perform a road test to verify repair.
If the DTC does not return:
Repair complete, Generate readiness code. Refer to READINESS CODE .
-- End diagnosis.
If the DTC does return and no malfunction is detected in the wiring and the voltage supply was not OK:
-- Replace the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248-. Refer to DIESEL DIRECT FUEL INJECTION ECM, REPLACING .
-- Assembly is performed in the reverse of the removal.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .