P0957 — Auto Shift Manual Mode Circuit Low

How much does it cost to fix P0957?

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.

How do I diagnose P0957 myself?

Start with a scan: confirm P0957, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the auto shift manual mode, and verify the suspect component against live data before buying parts.

What does OBD2 code P0957 mean?

P0957 — Auto Shift Manual Mode Circuit Low. 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, blown fuse feeding the circuit.

Will P0957 clear itself?

Sometimes P0957 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 P0957?

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.

When your vehicle's computer detects that an electrical circuit related to the automatic shift manual mode is holding voltage below specifications, it logs OBD2 trouble code P0957. This code falls under the powertrain category, meaning it involves either the engine, transmission, or the electronic systems that manage the connection between them. The phrase "circuit low" tells you the voltage on that particular wire has dropped close to ground level — essentially, the signal the computer expects to see is missing because something is pulling it down or shorting it out.

The affected circuit is responsible for communicating the driver's manual shift requests in vehicles equipped with automatic transmissions that offer a manual-style mode. The transmission control module relies on accurate voltage readings from this circuit to interpret whether you're requesting an upshift, downshift, or no request at all. When P0957 sets, the ECU has compared live sensor and actuator readings against factory-calibrated thresholds over multiple drive cycles and consistently found the voltage too low. It then stores a freeze frame snapshot — engine RPM, load, coolant temperature, and vehicle speed recorded at the exact moment of failure — which becomes your most valuable diagnostic clue.

Symptoms of P0957

• Check Engine Light illuminates on the dashboard
• Manual shift mode stops responding or behaves erratically
• The automatic transmission may feel sluggish or stuck in a fixed gear
• Intermittent operation of the affected system
• Reduced fuel efficiency in some driving conditions
• The vehicle may enter a protective limp mode with limited gear selection

Common Causes

The most likely source of P0957 is a wiring short to ground — a chafed wire insulation rubbed through until the copper conductor contacts bare metal. Here are the typical culprits, ranked from most to least frequent:

• Signal wire shorted to ground due to damaged insulation
• Failed auto shift manual mode sensor or actuator pulling the circuit low
• Corroded, loose, or damaged connector with poor electrical contact
• Blown fuse supplying power to the circuit
• Open circuit or broken wire interrupting voltage delivery
• Control module driver output failure (rare)
• Missing supply voltage to the component from a related circuit

How to Diagnose P0957

1. Hook up an OBD2 scanner, retrieve P0957, and record the freeze frame data before clearing anything. This snapshot tells you engine RPM, load, coolant temperature, and speed at the moment of failure.
2. Check for related diagnostic trouble codes — secondary codes often point to the real problem. Also search for manufacturer TSBs for your specific make and model on nhtsa.gov or the brand's technical portal.
3. Perform a visual inspection of the wiring harness and connectors feeding the auto shift manual mode circuit. Look for cracked insulation, corrosion at the pins, wires pulled out of connectors, and any signs of heat damage.
4. Measure voltage at the component connector first — confirm battery voltage is present. Then check resistance from the signal wire to ground; a reading near zero ohms confirms a short to ground in the harness.
5. If voltage checks out, test the component itself: reference voltage, ground reference, and signal output at the connector. Swap known-good parts if available to isolate whether the sensor or actuator is faulty.
6. Wiggle-test the harness while monitoring live data — any signal dropout points to an intermittent open or broken wire inside the insulation.
7. After repairs, clear the code and drive through conditions matching the freeze frame data. P0957 returning confirms the repair is incomplete.

Repair Options and Costs

Tackle the cheapest probable cause before replacing expensive components. Three main repair paths exist for P0957, with typical parts and labor at independent shops:

• Wiring repair or connector replacement: $80–$250. Often just a section of chafed harness or a corroded connector that needs cleaning or replacement.
• Sensor or actuator replacement: $150–$500. If testing confirms the component itself is failed, it will need swapping for an OEM or quality aftermarket unit.
• Control module repair: $300–$1,000. Sometimes the TCM or PCM has an internal driver failure — repair or replacement is pricier but less common.

Overall, fixing P0957 typically runs between $80 and $1,000. An accurate diagnosis before buying parts is the single best way to keep costs down — the worst-case scenario is rarely the first thing to check.

Can You Drive With P0957?

In most cases, yes — the vehicle stays drivable, though you may notice limited transmission function or the manual shift mode becoming unavailable. The car usually continues operating in default automatic mode. However, if P0957 comes alongside stalling, no-start conditions, or brake/steering warnings, treat it as a priority repair.

Related OBD2 Codes

• P0900: Clutch Actuator Circuit/Open
• P0901: Clutch Actuator Circuit Range/Performance
• P0902: Clutch Actuator Circuit Low
• P0903: Clutch Actuator Circuit High
• P0904: Gate Select Position Circuit
• P0905: Gate Select Position Circuit Range/Performance