P2670 code meaning
Actuator Supply Voltage B Circuit Low
Powertrain system Generic code P26xx codes Check engine light
What P2670 means
P2670 is set when the second high-side actuator supply delivers too little voltage while it is switched on, which nearly always means a short to ground somewhere on the supply line or in a load connected to it. GM documents it in several controllers. In the 16OBDG08 TCM tables for Silverado and Sierra a ground short is recognised at an impedance of 0.43 ohm or less, confirmed after three events, Type A. GM's 2023 TCM compares the supply voltage with battery voltage and also watches the average current, 60 ms to fail, Type A. In GM's hybrid tables (Volt THPC in 16OBDG01, HPC1 in 19OBDG01) high side driver 2 reports the short within about 0.13 s, again Type A after one trip. Solenoids on that supply drop out, so the transmission enters a failsafe mode.
P2670 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 P2670
- Failsafe gear, no normal shifting
- MIL on immediately
- Further solenoid circuit codes stored alongside
Common causes of P2670
- Most likelySupply wire chafed and shorted to ground
- PossibleShorted solenoid on the supplied group pulling the line down
- Less likelyFaulty high-side driver in the controller
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 P2670 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. |
| 70 | The exact fault in that area. |
What to do next
- Note P2670 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 P2670
What does P2670 mean?
P2670 means "Actuator Supply Voltage B Circuit Low". P2670 is set when the second high-side actuator supply delivers too little voltage while it is switched on, which nearly always means a short to ground somewhere on the supply line or in a load connected to it. It is a generic code, so it means the same on every make.
Is it safe to drive with P2670?
Drive gently and only to a workshop. With P2670 the car can go into limp mode (reduced power) to protect itself.
Will P2670 fail an emissions test?
Yes, it can. P2670 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 P2670 to fix?
Difficulty: hard. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P2670 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.