Intake Air Heater/Cold Start Indicator Fault
Indicates a problem with the intake air heater circuit.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The intake air heater helps the engine start in cold weather by warming the air going into the engine. If there's a fault, it might not heat the air properly, making it harder to start on cold days.
What the computer is actually seeing
The engine control module (ECM) monitors the intake air heater's operation and looks for expected current flow (typically around 5-10 amps). If it sees an open circuit (no current) or an overcurrent, it sets this code.
What a healthy reading looks like
5-10 amps of current flow through the intake air heater circuit when activated.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the vehicle's coolant temperature. If it's below 50°F (10°C), the heater should be active. If not, proceed to step 2.
- 22. Inspect the wiring and connectors for any visible signs of damage or corrosion. Repair as necessary.
- 33. Measure the current at the intake air heater while starting the engine. Ensure it’s between 5-10 amps. If not, replace the heater if it’s open or shorted.
- 44. If the heater is functioning correctly, check the ECM for faults. Perform a software update if one is available.
- 55. Clear the code and run the engine to see if it returns.
Common causes
- Faulty intake air heater
- Open circuit in the wiring
- Short to ground or battery
- Faulty ECM
- Corroded connectors
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderate severity. The vehicle may start hard in cold weather, so plan to fix it soon, especially if temperatures drop.
If I clear the code, will it come back?
If the underlying issue isn't fixed, the code will likely return.
Why does this code pair with others like SPN 0351?
Codes like SPN 0351 are related because they pertain to the same intake air heating system, indicating that multiple components or circuits may be affected.
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