Fuel Fired Heater Performance
P2030 indicates the fuel fired heater system is not operating at peak efficiency or is malfunctioning. This code is set when the PCM detects performance issues with the auxiliary fuel heater, which is responsible for cabin heating and engine prewarming in diesel or cold-climate vehicles.
What You Might Notice
- No heat in passenger compartment
- Excessive heat in passenger compartment
- Climate control blower temporarily disabled
- Delayed cabin heating
- Inconsistent heater operation
Most Common Causes
- 1
Defective temperature sensor
Air intake or coolant temperature sensor is malfunctioning or reading incorrectly, preventing proper heater control feedback to the PCM.
- 2
Bad fuel fired heater injector
The heater injector is clogged, leaking, or electrically failing, preventing fuel from being properly sprayed into the heater combustion chamber.
- 3
Faulty heater burner or igniter
The ignition element or burner assembly in the fuel fired heater is defective, preventing ignition or sustained combustion.
- 4
Wiring or connector issues in heater circuit
Open, shorted, or corroded wiring or connectors in the fuel fired heater circuit are preventing proper electrical signal transmission to PCM.
How to Diagnose It
- 1
Check Defective temperature sensor — Air intake or coolant temperature sensor is malfunctioning or reading incorrectly, preventing proper heater control feedback to the PCM.
- 2
Check Bad fuel fired heater injector — The heater injector is clogged, leaking, or electrically failing, preventing fuel from being properly sprayed into the heater combustion chamber.
- 3
Check Faulty heater burner or igniter — The ignition element or burner assembly in the fuel fired heater is defective, preventing ignition or sustained combustion.
- 4
Check Wiring or connector issues in heater circuit — Open, shorted, or corroded wiring or connectors in the fuel fired heater circuit are preventing proper electrical signal transmission to PCM.
How to Fix It
- 1
Test and replace temperature sensors
Use a DVOM to test air intake and coolant temperature sensor readings against specifications. Replace any sensor reading outside manufacturer parameters.
- 2
Inspect and clean or replace fuel heater injector
Remove the fuel fired heater injector and inspect for clogs or damage. Clean with appropriate solvent or replace if defective. Verify proper fuel pressure to the injector.
- 3
Test and replace heater burner/igniter assembly
Use a diagnostic scanner to command the heater on and listen for ignition. If no ignition occurs, test igniter voltage with DVOM and replace the burner/igniter assembly if faulty.
- 4
Inspect wiring and connectors in heater circuit
Visually inspect all wiring harnesses and connectors related to the fuel fired heater system for corrosion, damage, or loose connections. Repair or replace damaged wiring and secure all connectors. Clear the code and retest.
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