P2671 code meaning
Actuator Supply Voltage B Circuit High
Powertrain system Generic code P26xx codes Check engine light
What P2671 means
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.
P2671 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2671
- Warning lamp after the next start
- Often no immediate shift complaint
- Failsafe may not engage correctly if another fault occurs
Common causes of P2671
- Most likelySupply line shorted to another powered circuit
- PossibleHigh-side switch in the controller stuck closed
- Less likelyMoisture or corrosion bridging pins in the transmission connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Actuator supply bControl moduleWiring harness
What each part of P2671 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 6 | Area: computer (engine control module) and output circuits. |
| 71 | The exact fault in that area. |
What to do next
- Note P2671 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2671
What does P2671 mean?
P2671 means "Actuator Supply Voltage B Circuit High". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P2671?
Drive gently and only to a workshop. With P2671 the car can go into limp mode (reduced power) to protect itself.
Will P2671 fail an emissions test?
Yes, it can. P2671 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2671 to fix?
Difficulty: hard. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P2671 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.