P2671 — Actuator Supply Voltage "B" Circuit High
P2671 — Actuator Supply Voltage "B" Circuit High. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: corroded, loose or damaged connector, control module driver fault, faulty sensor or actuator of the affected circuit.
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 P2671 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 With the actuator supply voltage "B" disconnected, measure signal voltage at the harness connector: a high reading with the component unplugged indicates a short to power in the harness; if it drops to normal, the component itself is faulty.
- 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 P2671 does not return.
Approximate repair cost
Repair cost depends on which component actually failed. Typical scenarios for P2671 (parts and labor, USD, independent shop rates): Control module repair: $300–$1,000; Replace the faulty sensor or actuator: $150–$500; Repair wiring or connectors: $80–$250. Overall, fixing P2671 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
Will P2671 clear itself?
Sometimes P2671 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.
Is it safe to drive with P2671?
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.
What are the symptoms of P2671?
Drivers most often notice: Check Engine Light on, increased fuel consumption in some cases, possible limp mode depending on the affected component, the affected system operates intermittently or not at all.
What is the most common cause of P2671?
The most common causes are: corroded, loose or damaged connector, control module driver fault, faulty sensor or actuator of the affected circuit.
How much does it cost to fix P2671?
Control module repair — $300–$1,000; Replace the faulty sensor or actuator — $150–$500; Repair wiring or connectors — $80–$250. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.
What does P2671 mean?
P2671 is logged by the onboard diagnostics when the sensor and actuator circuits does not behave as expected. The official definition is “Actuator Supply Voltage "B" Circuit High”. This is a powertrain (engine/transmission) category code.
“Circuit high” means the control module sees a voltage on the actuator supply voltage "B" circuit that is above the expected range — typically close to battery voltage. Physically this points to a short to a power feed, a broken ground return, or a failed component pulling the signal line high.
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 P2671 — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.
Common symptoms of P2671
- Check Engine Light on
- increased fuel consumption in some cases
- possible limp mode depending on the affected component
- the affected system operates intermittently or not at all
What causes P2671?
- open ground return of the actuator supply voltage "B"
- signal wire shorted to battery positive
- failed actuator supply voltage "B" pulling the signal high
- open or shorted wiring in the circuit
- poor ground connection
- corroded, loose or damaged connector
- faulty sensor or actuator of the affected circuit
- control module driver fault
- blown fuse feeding the circuit
How to diagnose P2671
- Connect an OBD2 scanner, confirm P2671 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.
- With the actuator supply voltage "B" disconnected, measure signal voltage at the harness connector: a high reading with the component unplugged indicates a short to power in the harness; if it drops to normal, the component itself is faulty.
- 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 P2671 does not return.
How to fix P2671
Start with the cheapest and most common causes before replacing expensive parts:
- Control module repair — $300–$1,000
- Replace the faulty sensor or actuator — $150–$500
- Repair wiring or connectors — $80–$250
How much does it cost to fix P2671?
Repair cost depends on which component actually failed. Typical scenarios for P2671 (parts and labor, USD, independent shop rates):
- Control module repair: $300–$1,000
- Replace the faulty sensor or actuator: $150–$500
- Repair wiring or connectors: $80–$250
Overall, fixing P2671 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 P2671?
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.