P237DExhaust Heat Exchanger Exhaust Bypass Valve A Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P237D concerns the same drive line as P237C, the one that operates bypass flap A of an exhaust heat recovery unit, but here the module measures a voltage that sits too low – the usual picture of a control wire touching ground or an actuator shorted internally. Moisture in a connector under the car can produce exactly that. Ford names P237D in two full-hybrid bulletins: SSM 51921 for 2.5L Maverick hybrids built for model years 2022–23, where water inside the heat exchanger is the cause and the unit is renewed, and SSM 53003 for the PowerBoost F-150 hybrid of model years 2021 to 2023, which points to the heat exchanger actuator and supplies a replacement kit. Both bulletins describe a lit MIL. Unlike P237E, the short goes to ground; with the flap uncontrolled, warm-up can take longer.
- What you may notice
- Check engine light on
- Slower heater response after a cold start
- Car otherwise drives normally
- Likely causes
- LikelyWater in the heat exchanger or its actuator shorting the drive (Maverick)
- PossibleActuator internally shorted to ground
- PossibleControl wire chafed through against the body or exhaust bracket
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €80 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.