1996 PCED OBDI | SECTION 18: Diesel Diagnosis — 7.3L DI Engine |
S1 DIAGNOSTIC TROUBLE CODE (DTC) 0380: CHECK IF GLOW PLUGS ARE CONTINUOUSLY ON
- DTC 0380 is set when the PCM detects a malfunction in the glow plug relay control circuit.
- Possible causes:
- Shorted to power
- Open/grounded circuit
- Open fuse (F-Series — fuse 22, Econoline — fuse U)
- Worn or damaged glow plug relay
- Disconnect glow plug relay coil connector (hard shell).
- Turn key to on position.
- Measure voltage at Circuit 16 (R/LG) Pin B to ground.
Is battery positive present?
| Yes | No |
|---|
| GO to S2. | OPEN ignition power circuit. REPAIR short to ground. CHECK fuse (F-Series — fuse 22, Econoline — fuse U). |
S2 RELAY COIL RESISTANCE TEST
- Key off.
- Measure resistance of coil at points A and B.
Is resistance between 5 ohms and 15 ohms?
| Yes | No |
|---|
| GO to S3. | REPLACE glow plug relay. RETEST system. |
S3 CHECK SHORT TO POWER
- Key off.
- PCM disconnected.
- Install breakout box.
- Measure voltage from test Pin 101 to chassis ground.
Is B+ present?
| Yes | No |
|---|
| SERVICE short to power. RERUN Scan Tool Diagnostic Test. | GO to S4. |
S4 GLOW PLUG CIRCUIT SHORT TEST
- Key off.
- Measure resistance from ground to glow plug relay harness connector Pin A Circuit 1086 (P/O).
Is the resistance less than 5 ohms?
| Yes | No |
|---|
| FIX short to ground. | GO to S5. |
S5 CHECK CIRCUIT FOR OPEN
- With breakout box installed and PCM disconnected, measure resistance from Pin 101 to glow plug relay harness connector Pin A Circuit 1086 (P/O).
Is the resistance less than 5 ohms?
| Yes | No |
|---|
| REPLACE PCM. | SERVICE open in Circuit 1086 (P/O). RETEST system. |
S: Introduction