Fault Family
System: Powertrain (P-Codes)
2 SAE Codes
Fuel Fired Heater Performance
Diagnostic & Technical Explanation
P2029 (Fuel Fired Heater Disabled) applies to an auxiliary fuel-fired combustion heater used on some trucks and cold-climate diesels to speed engine warm-up and support cabin heat at idle, and is distinct from the vehicle's own combustion process. The control module disables the unit or logs a performance fault when it cannot establish or sustain combustion, most often from a fouled glow-plug igniter, a clogged fuel metering pump or nozzle, or a blocked combustion air or exhaust path.
These 2 diagnostic trouble codes share one
detection mechanism and one repair path, which is why MechanicDB groups them into a single
authored fault family rather than repeating the same explanation 2 times.
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)