P2029

Fuel Fired Heater Disabled

Q: Is it safe to drive with P2029?

Yes. The fuel-fired heater only assists warm-up in cold conditions, so the engine drives normally without it — you may just see slower heat and the warning light.

Q: Can I just clear P2029?

It will return if the module still has a reason to disable the heater. Address the companion codes or heater fault first, then clear.

Auxiliary emissions / cold-start heating Generic OBD-II Low

What it means

P2029 means the control module has disabled the fuel-fired heater — an auxiliary burner used on some vehicles to warm the coolant or cabin faster in cold weather. It's typically set because a fault or an out-of-range condition made the module shut the heater off, and it does not affect the engine's ability to start or run.

Low

Can I keep driving? Safe to drive; the engine runs normally. You may only notice slower cabin or engine warm-up in cold weather.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Slow cabin or engine warm-up in cold weather
Auxiliary (fuel-fired) heater not operating

Common causes

Most likely first

Fuel-fired heater has been disabled by the control module due to a fault or unmet operating conditionsLikely
Fault in the heater's control circuit or wiringCommon
Low fuel or conditions outside the heater's operating rangeCommon
Faulty fuel-fired heater unitLess often

How to diagnose & fix

Work through it in order

Read freeze-frame and any companion codes to see why the module disabled the heater.
Confirm operating conditions (fuel level, temperature, battery voltage) are within the range the heater needs.
Inspect the heater's wiring, connector, and fuse for faults.
Have the fuel-fired heater unit tested per the manufacturer's procedure and replace if faulty.

FAQ

Quick answers

Is it safe to drive with P2029?+

Yes. The fuel-fired heater only assists warm-up in cold conditions, so the engine drives normally without it — you may just see slower heat and the warning light.

Can I just clear P2029?+

It will return if the module still has a reason to disable the heater. Address the companion codes or heater fault first, then clear.

Read & clear P2029 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX