OBD-II code · Powertrain (generic, extended)
P2634 Fuel Pump B Control Circuit High
Voltage on the second fuel pump control line is above the expected window. Typical causes are a short to battery or an open motor winding.
Is it safe to drive with P2634?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyControl wire shorted to B+
- PossibleOpen motor winding
- Less likelyConnector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Hard start, no start, or stalling under load
- Power loss especially at high load or rpm
- Possible long cranking time
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.8–3.5 h
- Emissions test
- Usually unaffected
- Parts involved
- Fuel Pump B, Wiring Harness
Related codes
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.