Fuel Fired Heater Disabled
The P2029 code indicates that the engine control module (ECM) has detected a fault in the fuel fired heater system, typically used in diesel vehicles to preheat the engine coolant. This heater is often disabled due to electrical issues, such as a blown fuse, faulty relay, or wiring problems, or due to a malfunctioning heater unit itself. The system may be disabled to prevent further damage or safety hazards.
01. Most Common Causes
- Blown fuse or faulty relay for the fuel fired heater
- Damaged wiring or connectors in the heater circuit
- Malfunctioning fuel fired heater unit
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced cabin heat or longer warm-up time in cold weather
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for related codes.
Step 2: Inspect the fuel fired heater fuse and relay; replace if blown or faulty.
Step 3: Visually inspect wiring and connectors for damage, corrosion, or loose connections.
Step 4: Test the heater unit's resistance and power supply; replace if defective.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, it is generally safe to drive, but you may experience reduced cabin heat and longer engine warm-up in cold weather. The vehicle will not be damaged, but the heater should be repaired for comfort.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the cause. A fuse or relay replacement is cheaper, while a heater unit replacement may cost more.