P2809

Code

Generic P — Powertrain

Pressure Control Solenoid G Stuck On

Brand: Generic

Type: P — Powertrain

Views: UK: 20 EN: 27 RU: 24

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Short to ground on the solenoid control circuit
Failed/shorted solenoid coil (internal short)
Stuck or mechanically seized valve inside the solenoid
Contaminated/dirty transmission fluid or debris blocking valve
Corroded or loose connector pins
Broken or chafed wiring harness

Symptoms

Harsh, delayed or erratic shift engagement
Transmission stuck in a gear or in limp mode
Higher than normal transmission line pressure
Reduced drivability and fuel economy
Transmission overheating or whining
MIL/Check Engine Light on with stored P2809

What to check

Scan for codes and record freeze-frame and live data (solenoid command vs feedback if available)
Check transmission fluid level and condition (metal particles or contamination)
Visually inspect solenoid connector and wiring for damage, corrosion or pin push-out
Backprobe the solenoid control circuit and measure voltage/duty when commanded
Measure solenoid coil resistance (compare to spec)
Perform wiggle test while monitoring live data for intermittent faults

Signal parameters

Typical solenoid coil resistance (generic): ~5–50 ohms (vehicle-specific — consult spec)
Control type: PWM or switched 12 V with ground-side switching depending on vehicle
PWM frequency (typical range): ~50–250 Hz for many transmission solenoids (vehicle-specific)
Duty cycle range: 0–100% (TCM commands varying duty to modulate pressure)
When 'stuck ON' the control line may show near-continuous drive duty or a short to ground/power

Diagnostic algorithm

Read and record all transmission-related DTCs and freeze-frame data. Note whether other solenoid or pressure codes are present.
Verify correct transmission fluid level and condition. If fluid is heavily contaminated, consider fluid/filter service before further testing.
Clear codes and attempt to reproduce. Monitor live data: observe solenoid G command (duty/voltage) and any reported pressure or feedback values.
Visually inspect the solenoid G connector, pins and wiring for corrosion, damaged insulation, pinbacking or moisture intrusion.
With harness unplugged, measure solenoid coil resistance at the connector. Compare to manufacturer spec. Unreasonable low resistance suggests internal short; open/high resistance suggests open coil.
Backprobe the connector with the system running/commanding the solenoid. Measure voltage and/or PWM duty at the control wire while commanding ON and OFF. Look for continuous drive or an always-on signal when command is OFF.
Check for a short to ground or short to battery on the control wire using an ohmmeter/voltmeter. Wiggle the harness along its routing while monitoring to find intermittent shorts.
If wiring and connector are good but solenoid shows abnormal behavior, bench-test or swap the solenoid with a known-good unit to confirm solenoid failure.
If solenoid and wiring test good and the TCM continues to show the circuit stuck on condition, test the TCM output driver or consider module reprogramming/replacement following manufacturer procedures.
After repair, clear codes and perform a road test under various conditions to verify proper shift quality and that code does not return.

Likely causes

Wiring short to ground at or near the solenoid connector
Solenoid coil failure (internal short or internal sticking)
Connector corrosion or poor connection causing incorrect feedback
Contaminated fluid causing the valve to stick

Fault status

⚠️ Status

Pressure Control Solenoid G Circuit Stuck On — the TCM/PCM detects solenoid G remains energized or reports continuous on-state. May cause elevated line pressure, harsh shifts or limp mode.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.5-3.0 hours