OBD-II code · Powertrain (generic, extended)
P2029 Fuel Fired Heater Disabled
The fuel-fired auxiliary heater (used to warm coolant or DEF on cold start) has been disabled by the control module — typically because of repeated start failures, low-voltage supply, or a self-protection condition.
Is it safe to drive with P2029?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyHeater glow plug failed
- PossibleLow battery voltage triggered lockout
- PossibleFuel supply starved — empty tank or pump weak
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–4 h
- Emissions test
- Usually unaffected
- Parts involved
- Fuel Fired Heater, Heater Glow Plug, Heater Fuel Pump
Related codes
- P2026EVAP Fuel Vapor Temperature Sensor Circuit Low Voltage
- P2027EVAP Fuel Vapor Temperature Sensor Circuit High Voltage
- P2028EVAP Fuel Vapor Temperature Sensor Circuit Intermittent
- P202AReductant Tank Heater Control Circuit/Open
- P202BReductant Tank Heater Control Circuit Low
- P202CReductant Tank Heater Control Circuit High
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.