P2606
Intake Air Heater B Circuit Range/Performance
Cold-start / intake air heating
Generic OBD-II
Low
What it means
P2606 means the intake air heater 'B' circuit isn't performing as the control module expects. This heater warms incoming air to help cold starts and reduce cold-run emissions, so a fault mainly shows up as harder starting or rougher running in cold weather — it does not stop the engine from running.
Low
Can I keep driving? Safe to drive. You may notice harder cold starts or rougher running until warm, but the engine will still run.
Common symptoms
What you'll notice
- Check-engine light on
- Harder starting in cold weather
- Rougher idle or slight hesitation until the engine warms up
- Often no noticeable symptom in warm conditions
Common causes
Most likely first
- Failed intake air heater element (heater 'B')Likely
- Faulty intake air heater relayCommon
- Open, shorted, or corroded wiring in the heater circuitCommon
- Poor connection or bad ground at the heater connectorLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for related intake-air-heater circuit codes (P2607, P2608).
- Inspect the heater element, relay, and wiring for damage, corrosion, or loose connectors.
- Measure the heater element resistance and check for supply voltage and a good ground when commanded on.
- Replace the heater element or relay as indicated, then clear and re-test on a cold start.
FAQ
Quick answers
Is it safe to drive with P2606?+
Yes. The intake air heater only aids cold starts and warm-up, so the main effect is harder cold starting and slightly rough running until warm.
Can I just clear P2606?+
You can, but it will return once the heater circuit is used again in cold conditions unless the fault is repaired.
Related codes
Often seen with P2606
Read & clear P2606 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX