Glow Plug Relay, Checking
Special tools and workshop equipment required
- Multimeter.
- wiring diagrams.
Test requirements
- The fuse for the engine electronics OK.
- The Ground (GND) connections at the engine and transmission OK.
- The battery voltage at least 12.5 V.
- The generator OK.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK
Start diagnosis
-- Using a Multimeter, check the following wiring connection for voltage.
| Glow Plug Relay -J52- socket | Measure to |
|---|---|
| 2 | Engine Ground (GND) |
Specified value: 12.5 V
If the specified value was not obtained:
-- Using a Multimeter --, check the Glow Plug Relay -J52- socket 2 to the Battery (+) for an open circuit or short to Ground (GND).
-- Check the electrical harness connectors for damage, corrosion, loose or broken terminals.
-- If necessary, repair the wiring connection.
If no malfunctions are found in the wiring:
Checking relay activation
-- Switch the ignition on.
-- Using a Multimeter --, check the following wiring connection for voltage.
| Glow Plug Relay -J52- socket | Measure to |
|---|---|
| 4 | Engine Ground (GND) |
Specified value: 12.5. battery voltage.
-- Switch the ignition off.
If the specified value was not obtained:
-- Using a Multimeter --, check the Glow Plug Relay -J52- socket 2/86 to the Ignition/Starter Switch -D- electrical harness connector terminal for an open circuit.
Specified value: 1.5 Ω.
If the specified value was not obtained:
-- Check the Glow Plug Relay -J52- socket 28/15 to the Ignition/Starter Switch -D- electrical harness connector terminal for an open circuit or a short to Ground (GND).
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
-- If necessary, repair the wiring connection.
If no malfunctions are found in the wiring:
Checking Ground (GND)
-- Using a Multimeter --, check the Glow Plug Relay -J52- socket 3/85 to the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- electrical harness connector terminal T80/50 for an open circuit.
Specified value: 1.5 Ω.
If the specified value was not obtained:
-- Check the Glow Plug Relay -J52- socket 3/85 to the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- electrical harness connector terminal T80/50 for an open circuit or a short to Ground (GND).
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
-- If necessary, repair the wiring connection.
If no malfunctions are found in the wiring and the voltage supply was OK:
-- Replace the Glow Plug Relay -J52-.
-- Perform a road test to verify repair.
If the fault does not return:
Repair complete, Generate readiness code. Refer to READINESS CODE .
-- End diagnosis.
If the fault does return and no malfunction is detected in the wiring and the voltage supply was OK:
-- Replace the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248-. Refer to ENGINE CONTROL MODULE, 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 .
End diagnosis.