P081BStarter Disable Circuit High
- Generic OBD-II code · Powertrain
- How the car detects it
- The starter disable line carries the signal 'park or neutral – start allowed' from the transmission module, or its built-in range switch, to the body or engine module, which only then releases the starter. On Saab's 2010 9-5 automatic the line is open in a drive range (0 V at the body module) and closed in P or N (12 V). P081B means the start release line stays at positive, so the 'P/N' level is present in a drive range. Saab's 2012 9-3 checks it only outside P and N, with 9–18 V and not in limp mode. A short to positive could in principle allow a start in gear; the diagnosis catches it, and Saab names as the effect that the engine may not start because the release is refused.
- What you may notice
- Engine does not start or starts unreliably
- Start release in the wrong range possible (safety risk)
- No check engine lamp
- Likely causes
- LikelyP/N line shorted to positive (chafed against a supply wire)
- PossibleMoisture or corrosion in the connector
- RareTransmission module output stage faulty
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.