1996 PCED OBDI | SECTION 18: Diesel Diagnosis — 7.3L DI Engine |
R1 DIAGNOSTIC TROUBLE CODE (DTC) 0381
- DTC 0381 is set when the PCM detects a malfunction in the glow plug warning lamp circuit.
- Possible causes:
- Open/grounded circuit
- Open WAIT TO START lamp
- Open fuse (F-Series — fuse 17, Econoline — fuse 18)
- Start engine.
- Key on, engine running.
Does WAIT TO START lamp remain on?
R2 CHECK CIRCUIT 464 (BK/PK) FOR SHORT
- Key off.
- Disconnect PCM.
- Key on, engine off.
Is WAIT TO START lamp on?
Yes | No |
SERVICE ground short in Circuit 464 (BK/PK) between WAIT TO START lamp and PCM. RERUN Scan Tool Diagnostic Test. | REPLACE PCM. RERUN Scan Tool Diagnostic Test. |
R3 CHECK FUSE FOR OPEN
- Key off.
- Check fuse (F-Series — fuse 17, Econoline — fuse 18) for continuity.
Is fuse OK?
R4 CHECK WARNING LIGHT BULB FOR OPEN
- Disconnect WAIT TO START lamp.
- Check bulb for continuity.
Is bulb OK?
Yes | No |
GO to R6. | REPLACE bulb. RERUN Scan Tool Diagnostic Test. |
R5 CHECK CIRCUIT 640 (R/Y) FOR GROUND SHORT
- Disconnect WAIT TO START lamp.
- Measure resistance between Circuit 640 (R/Y) and chassis ground.
Is resistance greater than 10,000 ohms?
Yes | No |
REPLACE fuse. RERUN Scan Tool Diagnostic Test. | SERVICE ground short in Circuit 640 (R/Y). REPLACE fuse. RERUN Scan Tool Diagnostic Test. |
R6 CHECK FOR OPEN CIRCUIT 640 (R/Y)
- Key off.
- Disconnect WAIT TO START lamp.
- Key on, engine off.
- Measure voltage on Circuit 640 (R/Y) at warning light harness connector.
Is B+ present?
Yes | No |
GO to R7. | SERVICE open in Circuit 640 (R/Y) between fuse and WAIT TO START lamp. RERUN Scan Tool Diagnostic Test. |
R7 CHECK FOR OPEN IN CIRCUIT 464 (BK/PK)
- Disconnect PCM.
- Install breakout box.
- Measure resistance in Circuit 464 (BK/PK) between the WAIT TO START lamp and Pin 80 on the breakout box.
Is resistance less than 5 ohms?
Yes | No |
REPLACE PCM. RERUN Scan Tool Diagnostic Test. | SERVICE open in Circuit 464 (BK/PK). RERUN Scan Tool Diagnostic Test. |