What it means
The control circuit of intake air heater C reports a circuit low condition. Cold-start preheating cannot be commanded as expected.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Intake air heater C warms incoming air to help the engine start and run cleanly in cold conditions. The control module monitors the heater C control circuit and sets P2CE3 when its signal is lower than expected, which can happen when the wire or heater element is shorted to ground.
Common causes
Most likely first.
- Control wire shorted to ground
- Heater element shorted
- Connector pins corroded - high contact resistance
Symptoms
- Check-engine light
- Hard starting in cold weather
- Rough running or white exhaust smoke after a cold start
How to diagnose it
- Record freeze-frame data and related intake-heater codes, and note whether symptoms occur during cold starts.
- Inspect heater C's wiring and connector for chafing against metal, moisture, corrosion, or damaged insulation that could short the circuit to ground.
- With the circuit safely disabled according to the manufacturer's procedure, check heater C's control wire for an unintended ground connection.
- Test the heater C element for a short and check its connector contacts for corrosion or damage, comparing results with the manufacturer's specification.
- If no short is found in the wiring or heater, test the control module output and circuit response using the manufacturer's diagnostic procedure.
Common fixes
- Repair chafed or pinched wiring that is shorting the heater C control circuit to ground.
- Clean or replace corroded heater C connector terminals.
- Replace the intake air heater C element if it is confirmed shorted.
- Repair a confirmed fault in the heater C control circuit or module output.
Can I keep driving?
The vehicle may start and run poorly in cold weather because heater C may not provide the needed preheating. Avoid repeated long cranking, and have the short repaired promptly because it can stress the circuit or its control components.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.