Intake Manifold Heater Circuit Failure
The intake manifold heater is not operating properly.
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 computer is checking if the intake manifold heater is working and has found it either isn't heating up when it should or there's a problem in the circuit.
What the computer is actually seeing
The engine control module (ECM) monitors the voltage from the intake manifold heater circuit; it expects to see close to battery voltage (about 12-14 volts) when it's activated. If it detects low voltage (under 5 volts) or an open circuit (no voltage), it triggers the code.
What a healthy reading looks like
Expected voltage at the heater should be 12-14 volts when the heater is active. Resistance of the heater should typically be between 1.5 to 3 ohms.
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. Inspect the wiring and connectors to the intake manifold heater for any visible damage or corrosion. Decision: Repair or replace any damaged components.
- 22. Measure the voltage at the intake manifold heater connector with the engine running and the heater activated (check if it’s on). Decision: If voltage is 12-14 volts, go to step 3; if not, trace back to find the fault in the circuit.
- 33. Test the resistance of the intake manifold heater itself using a multimeter. Decision: If resistance is between 1.5 and 3 ohms, the heater is likely good; if outside that range, replace the heater.
Common causes
- Faulty intake manifold heater
- Damaged wiring or connectors
- Open or short circuit in the heater circuit
- Failed engine control module (ECM)
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally drivable, but the engine may have reduced performance or start issues in cold weather due to the heater function failing.
Will this code come back after clearing?
If the underlying issue isn't fixed, the code will likely reappear after clearing.
Why does this code pair with other SPNs?
It's common for multiple codes to appear if there are related circuit issues or if multiple sensors share a common power source.
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