OBD-II code · Powertrain (generic, extended)
P2633 Fuel Pump B Control Circuit Low
Voltage on the second fuel pump control line is below the expected window. Usually a short to ground or a shorted motor winding.
Is it safe to drive with P2633?
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 ground
- PossibleInternal short in pump motor
- 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
- P0628Fuel Pump A Control Circuit Low
- P2630O2 Sensor Pumping Current Trim Circuit Low Bank 2 Sensor 1
- P2631O2 Sensor Pumping Current Trim Circuit High Bank 2 Sensor 1
- P2632Fuel Pump B Control Circuit / Open
- P2634Fuel Pump B Control Circuit High
- P2635Fuel Pump A Low Flow / Performance
- P2636Fuel Pump B Low Flow/Performance
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.