P1389
No Auto Shutdown (ASD) Relay Output Voltage at PCM
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The P1389 code on Chrysler, Dodge, and Jeep vehicles is a serious code indicating the PCM is not receiving output voltage from the Auto Shutdown (ASD) relay. The ASD relay is one of the most critical components in the Chrysler electrical architecture — it controls power to the fuel injectors, ignition coil(s), oxygen sensor heaters, and other essential engine systems. When the PCM cannot detect ASD relay voltage, it assumes a critical failure has occurred and shuts the engine down as a safety precaution.
This code can cause a complete no-start condition or sudden engine stalling while driving, which makes it a high-priority issue. The ASD relay is essentially the lifeline for the engine's fuel and ignition systems. Without it, there is no spark and no fuel injection. The good news is that the most common cause — a failed relay — is an inexpensive and easy fix. The ASD relay is located in the underhood fuse/relay box and typically costs $10–$20.
If replacing the relay doesn't solve the problem, check the associated fuse and then inspect the wiring between the relay box and the PCM for damage. Pay special attention to the PCM ground connections, as a corroded ground can prevent the PCM from reading the relay output even when the relay is working correctly. If the vehicle is stalling while driving, have it towed rather than risk being stranded in a dangerous location.
Severity
Symptoms
- •Engine stalls suddenly while driving and may not restart
- •Engine cranks but will not start at all
- •Loss of power to fuel pump and ignition system simultaneously
- •Check engine light illuminated (if engine runs long enough to set code)
- •Multiple electrical systems may seem dead with key on
Likely Causes
The ASD relay is the master power switch for the fuel injectors, ignition coil, and oxygen sensor heaters. If the relay fails internally, the PCM loses all sense voltage from these critical circuits, and the engine will not run.
Broken, chafed, or corroded wires in the ASD circuit prevent the relay output voltage from reaching the PCM. The PCM then shuts down the engine as a safety precaution.
A blown fuse in the ASD relay circuit removes power from the fuel and ignition systems. An underlying short circuit that blew the fuse should be identified and repaired to prevent recurrence.
A poor PCM ground connection or internal PCM failure can prevent the module from reading the ASD relay output voltage, even if the relay itself is functioning properly.
Estimated Cost
Professional Repair
Includes parts + labor
Common Fixes
- Replace the Auto Shutdown (ASD) relay
- Check and replace blown ASD fuse
- Inspect and repair wiring harness between ASD relay and PCM
- Clean and tighten PCM ground connections