P05E4Park Brake Sensor/Switch Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- The engine module reads the park brake status, directly or via another module, because strategies depend on it: a parked diesel filter regeneration only runs with the park brake applied (Navistar), idle shutdown and PTO logic use it, and Ford delays an automatic restart while the electric park brake moves. CARB requires such inputs to be monitored. The only documented user of this code family is Volvo Trucks: since OBD 2021 a second park brake sensor (about 0.5 V applied, 3.5 V released) must agree with the old switch; the engine module reports the fault. No passenger car maker uses it verifiably. P05E4 means the signal is below the lower limit: on a three-wire sensor a signal shorted to ground or a missing 5 V supply; on a simple ground switch it looks like a permanently applied brake.
- What you may notice
- Check engine light or OBD warning (heavy-duty)
- Park brake warning in the cluster
- Parked regeneration cannot be started
- Stop-start or idle shutdown not working
- Likely causes
- LikelySignal wire shorted to ground (chafed)
- PossibleSensor 5 V supply missing or shorted to ground
- PossibleSensor faulty internally
- RareModule input faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.