P0813
Reverse Output Circuit
Transmission
Generic OBD-II
Low
What it means
P0813 flags a fault in the reverse output circuit — the control-module output that signals reverse gear, commonly driving the reverse lamps and back-up-related systems. Reverse driving itself usually still works, but the reverse signal or lights may not, most often from a wiring fault, a bad switch, or a lamp-circuit problem.
Low
Can I keep driving? Yes — the car still drives, but reverse lights or back-up systems may not work, which is a safety concern; fix it soon.
Common symptoms
What you'll notice
- Reverse lights don't come on, or work intermittently
- Back-up camera or parking sensors may not activate
- Other reverse-related components not functioning correctly
- Check-engine light on
Common causes
Most likely first
- Faulty reverse output switch or sensorLikely
- Wiring or connector fault in the reverse output circuitCommon
- Loose or corroded connectorsCommon
- Failed body control module (BCM) or lighting control moduleLess often
- Reverse-lamp bulb, fuse, or relay faultLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm the fault is in the reverse output circuit.
- Check the reverse-lamp bulbs, fuse, and relay first — cheap and common.
- Inspect the reverse output wiring and connectors for damage or corrosion.
- Verify the reverse switch operates when the selector is in reverse.
- Test the BCM or lighting module output and repair as needed.
FAQ
Quick answers
Is it safe to drive with P0813?+
The car still drives, but reverse lights or back-up systems may not work — a safety concern when reversing at night or in traffic. Fix it soon.
Can I just clear P0813?+
It returns while the circuit fault remains. Repair the wiring, switch, or lamp circuit before clearing.
Related codes
Often seen with P0813
Read & clear P0813 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX