P2812

Code

Generic P — Powertrain

Pressure Control Solenoid G Control Circuit/Open

Brand: Generic

Type: P — Powertrain

Views: UK: 22 EN: 41 RU: 24

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Open or damaged wiring between TCM/PCM and solenoid
Corroded, bent or disconnected solenoid connector
Failed pressure control solenoid G (coil open)
Blown fuse or faulty relay affecting transmission electronics
Faulty TCM/PCM driver circuit
Poor ground or low battery voltage

Symptoms

Check Engine / Transmission warning light set
Transmission may go into limp/limited-slip mode
Harsh, delayed, or no shifting related to the affected pressure circuit
Reduced drivability and possible stuck gear
Diagnostic trouble code P2812 stored (may be accompanied by related transmission codes)

What to check

Read and record freeze frame and all stored codes, check for related transmission codes
Verify battery voltage (11–14.5 V) and charging system health
Visually inspect solenoid connector and wiring for damage, corrosion, pin push-out
Check relevant fuses and relays for continuity and correct operation
Back-probe the solenoid connector and measure coil resistance and control signal
Perform a wiggle test on harness while monitoring live data/voltage for intermittent faults

Signal parameters

Coil resistance (typical range): ~10–40 ohms (varies by vehicle). Open = infinite / OL; short ≈ 0–1 ohm.
Supply/reference voltage at solenoid connector: battery voltage (~11–14.5 V) with ignition ON.
Control output: TCM usually switches the solenoid to ground via PWM. Expected switching voltage: near 0 V when driver ON; near battery voltage when OFF.
PWM frequency: commonly 30–300 Hz (varies by design). Duty cycle varies with commanded pressure (0–100%).
Continuity: low resistance between solenoid pin and module control pin; high insulation to chassis ground except intended ground path.

Diagnostic algorithm

Confirm P2812 with a scan tool, record other codes and freeze frame data, then clear codes and attempt to re-create.
Check battery and charging voltage. Low voltage can cause false faults.
Visually inspect the solenoid G connector and harness to the TCM for damage, corrosion or rodent chew; repair any physical damage.
Disconnect harness at the solenoid. Measure coil resistance across solenoid terminals. Compare to spec; an open or out-of-range reading indicates a faulty solenoid.
With harness disconnected, check for supply voltage on the reference/supply pin (should be battery voltage) and check the control pin while commanding the solenoid ON/OFF with a scan tool. If no command or no change, suspect module or wiring.
Check continuity between the solenoid connector and the TCM control pin. Look for opens, high resistance, or shorts to ground/battery. Repair any harness faults.

Likely causes

Open circuit in the solenoid harness or a disconnected connector (most common)
Corroded or pushed-out terminal at the solenoid or module connector
Failed solenoid coil (open winding)
Intermittent wiring short to ground or to battery
Faulty TCM/PCM output driver (if wiring and solenoid test good)

Fault status

⚠️ Status

TCM detected an open or missing control signal on the Transmission Pressure Control Solenoid G circuit. The ECM/TCM set P2812 and may limit transmission functionality until the fault is corrected.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours