P2670 — Actuator Supply Voltage "B" Circuit Low
powertrain (engine/transmission)
Is it safe to drive?
Short-term driving is OK In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.
How to diagnose with an OBD scanner
- Read the code and freeze frame Connect an OBD2 scanner, confirm P2670 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the actuator supply voltage "B" for damage, corrosion, chafing or poor contact.
- Subsystem check Check for supply voltage at the actuator supply voltage "B" connector first; then measure resistance from the signal wire to ground — near-zero ohms confirms a short to ground in the harness.
- Subsystem check Measure reference voltage, ground and signal continuity at the component connector.
- Subsystem check Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
- Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2670 does not return.
Approximate repair cost
Repair cost depends on which component actually failed. Typical scenarios for P2670 (parts and labor, USD, independent shop rates): Replace the faulty sensor or actuator: $150–$500; Repair wiring or connectors: $80–$250; Control module repair: $300–$1,000. Overall, fixing P2670 usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Common questions
What does OBD2 code P2670 mean?
Actuator Supply Voltage "B" Circuit Low (P2670): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
Will P2670 clear itself?
Sometimes P2670 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.
How much does it cost to fix P2670?
Replace the faulty sensor or actuator — $150–$500; Repair wiring or connectors — $80–$250; Control module repair — $300–$1,000. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.
How do I diagnose P2670 myself?
Start with a scan: confirm P2670, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the actuator supply voltage "B", and verify the suspect component against live data before buying parts.
What is the most common cause of P2670?
The most common causes are: corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
What does P2670 mean?
Seeing P2670 on your scanner? The control unit has caught the sensor and actuator circuits operating outside its calibrated window. The formal description is “Actuator Supply Voltage "B" Circuit Low”, and the code is grouped under powertrain (engine/transmission) faults.
“Circuit low” means the voltage on the actuator supply voltage "B" circuit stays below the expected minimum — close to ground. The usual physical reasons are a short to ground, a chafed wire touching metal, a missing supply voltage, or a failed component dragging the signal down.
This code does not appear from a single bad reading: the module must see the fault condition repeat under defined operating conditions before it turns on the warning light. The freeze frame captured with P2670 — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.
Common symptoms of P2670
- possible limp mode depending on the affected component
- Check Engine Light on
- increased fuel consumption in some cases
- the affected system operates intermittently or not at all
What causes P2670?
- signal wire shorted to ground (chafed insulation)
- missing supply voltage to the actuator supply voltage "B"
- failed actuator supply voltage "B" pulling the signal low
- poor ground connection
- open or shorted wiring in the circuit
- control module driver fault
- faulty sensor or actuator of the affected circuit
- blown fuse feeding the circuit
- corroded, loose or damaged connector
How to diagnose P2670
- Connect an OBD2 scanner, confirm P2670 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Visually inspect the wiring harness and connectors related to the actuator supply voltage "B" for damage, corrosion, chafing or poor contact.
- Check for supply voltage at the actuator supply voltage "B" connector first; then measure resistance from the signal wire to ground — near-zero ohms confirms a short to ground in the harness.
- Measure reference voltage, ground and signal continuity at the component connector.
- Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
- Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2670 does not return.
How to fix P2670
Start with the cheapest and most common causes before replacing expensive parts:
- Replace the faulty sensor or actuator — $150–$500
- Repair wiring or connectors — $80–$250
- Control module repair — $300–$1,000
How much does it cost to fix P2670?
Repair cost depends on which component actually failed. Typical scenarios for P2670 (parts and labor, USD, independent shop rates):
- Replace the faulty sensor or actuator: $150–$500
- Repair wiring or connectors: $80–$250
- Control module repair: $300–$1,000
Overall, fixing P2670 usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Can you drive with P2670?
In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.