P2671Actuator Supply Voltage B Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2671 points to voltage on the second actuator supply when the controller has switched it off, so the line is fed from outside or the switch inside the module no longer opens. The solenoids on that supply can then no longer be de-energised as a group, which defeats the failsafe. GM tests this mostly at start-up or shut-down: in the 16OBDG08 TCM tables a short to power below 0.5 ohm is detected during initialisation with the driver off; the 2023 TCM checks at power-down whether the supply stays above 70 % of battery voltage, stores the result and sets the code at the next start as Type B. GM's hybrid HPC1 table of 2019 likewise rates it Type B. Ford's 2014 list contains P2671 without MIL. P2669 is the open circuit, P2670 the short to ground.
- What you may notice
- Warning lamp after the next start
- Often no immediate shift complaint
- Failsafe may not engage correctly if another fault occurs
- Likely causes
- LikelySupply line shorted to another powered circuit
- PossibleHigh-side switch in the controller stuck closed
- RareMoisture or corrosion bridging pins in the transmission connector
- 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: €100 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.