Jeep Fault Code
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Engine won't start or dies immediately; No fuel pump prime sound.
System
Not specified
Symptom
Engine won't start or dies immediately; No fuel pump prime sound.
Diagnosis & fix steps
Auto Shutdown (ASD) Relay Circuit.
LOGIC: The PCM has lost control of the ASD relay, which provides power to the fuel pump and ignition coil.
ACTION: 1. Swap the ASD relay with the Horn relay (they are usually identical) to test.
2. Check for a short in the fuel pump wiring.
FIX: Replace the ASD Relay or repair the fuel pump harness.
Red Seal field insights
The ASD relay is the "safety switch" of the Jeep. If the PCM detects a major electrical fault, it kills this relay to prevent a fire. Always check the harness near the fuel tank for pinches.
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
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