Accessory Control Relay Stuck On
The accessory control relay is not turning off properly.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer is trying to control an accessory relay but finds it's still powered on when it shouldn't be, disrupting normal function.
What the computer is actually seeing
The control module expects the accessory relay to be off but detects a voltage present at the relay terminal when it has commanded it off, usually less than 0.5 volts is expected when off.
What a healthy reading looks like
0.0 V when off, typically below 5.0 V when commanded off.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the power and ground to the accessory control relay. Ensure you have 12V at the power terminal and good ground.
- 22. Inspect the relay and its connections for corrosion or damage. Look for burnt contacts or broken pins.
- 33. Test or replace the relay to see if the issue persists. Use a known good relay to confirm operation.
- 44. Check the control signal from the ECM to the relay. You should see a low voltage signal when the relay is commanded off.
- 55. Inspect wiring for shorts or damage in the harness that could affect the relay's operation. Conduct a continuity test if necessary.
Common causes
- Sticky or faulty relay
- Wiring or connector issues
- Short circuit to power in the relay circuit
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive the vehicle with this code?
Yes, but it’s best to fix it soon to avoid draining the battery or malfunctioning accessories.
Will this code come back after clearing?
If the underlying issue isn’t fixed, it will likely return.
Why does this pair with other accessory-related codes?
Accessory circuits often share relays or wiring, leading to similar faults showing together.
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