P2607Intake Air Heater B Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2607 says the signal from the circuit of intake air heater B stays too low, which normally means a grounded control or feedback line, or a relay output pulled down. No manufacturer documents P2607 publicly. The closest published equivalents are Deutz, whose MD1 code list files an under-voltage or ground short at the preheating relay of heater A as P0541, and Volvo, whose 2020 engine software list contains the low-side code P2CE3-11 for heater C but none for B. CARB asks for the heater circuit to be monitored for current and voltage drop, which is how such a low reading becomes visible. P2608 is the high-side counterpart, P2605 the open circuit, P2606 the plausibility check. With heater B unusable, cold starts take longer and the engine smokes white at first.
- What you may notice
- Hard starting in cold weather
- White smoke after a cold start
- MIL on
- Likely causes
- LikelyControl or feedback wire chafed through to ground
- PossibleInternal short in the preheat relay
- RareMoisture or corrosion in a connector of the heater circuit
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.