Fault codeP0813
MODERATEReverse Output Circuit
What this code means
Reverse Output Circuit.
P0813 is a generic code: it means the same thing on every make. P0813 belongs to family P08xx — Transmission (continued). Its page explains how to read a code and groups all its codes by part.
Type of fault
The control unit has detected an electrical anomaly on this circuit without saying exactly which. Diagnosis starts with a visual check of the wiring and connector, then measuring the component — resistance, supply, ground — with a multimeter.
Gear selector position switches
These switches tell the control units whether the selector is in Park, Neutral, Drive or Reverse. They only allow starting in Park or Neutral, light the reversing lights and lock out reverse while moving on some gearboxes.
What you notice
The engine will not start in Park, reversing lights that do not work, shift indicator wrong on the dashboard.
How to check it
Check the switch on the gearbox, its adjustment with the selector cable and its connector, which is exposed to dirt and water. A slightly misadjusted selector cable is a frequent cause.
Watch it live in Klaro
With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:
- Vehicle speed
What to do
Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.
Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →
How to read this code
- PPowertrain
- 0standardised code
- 8Transmission (continued)
- 13P0813
Other codes for the same part
- P0801Reverse Inhibit Control Circuit Malfunction
- P0812Reverse Input Circuit
- P0817Starter Disable Circuit
- P0850Park / Neutral Switch Input Circuit
- P0851Park / Neutral Switch Input Circuit Low
- P0852Park / Neutral Switch Input Circuit High
- P0853Drive Switch Input Circuit
- P0854Drive Switch Input Circuit Low
- P0855Drive Switch Input Circuit High