P23A3Exhaust Heat Exchanger Exhaust Bypass Valve B Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- With P23A3 the module sees the control line of exhaust bypass valve B sitting lower than its commanded state allows, which usually means that the wire or the driver stage of the actuator has found a path to ground. Water or road salt in a connector under the vehicle is a typical trigger. P23A3 itself appears in no public manufacturer document. For the valve A equivalent P237D, Ford's SSM 53003 on 2021–2023 F-150 PowerBoost hybrids blames the actuator mounted on the heat exchanger and supplies service kit PL3Z-5K245-B, while SSM 51921 links the code on Mavericks to water inside the heat exchanger. CARB expects such outputs to be monitored for out-of-range circuit states. If the flap cannot be driven, warm-up may take longer; P23A4 is the opposite short.
- What you may notice
- Check engine light on
- Heater output builds up slowly after a cold start
- Fault may reappear after rain or washing
- Likely causes
- LikelyControl wire chafed through and touching body or exhaust ground
- PossibleMoisture or salt bridging pins in the actuator connector
- PossibleInternal short in the valve B actuator
- 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 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.