P2818 on GMC
Pressure Control Solenoid "H" Stuck On
P2818 on GMC vehicles indicates pressure control solenoid "h" stuck on. Au7o has documented this code across 1 GMC model — most commonly on Sierra 1500. SAE-defined generic powertrain/transmission code. Transmission pressure control solenoids meter line pressure to the clutch and band circuits so the transmission can change ratio smoothly. The transmission control module commands solenoid "H" off and then checks the resulting pressure, gear ratio and slip. P2818 sets when the module sees the hydraulic circuit still pressurised — the solenoid is stuck in the applied (on) state, either electrically or mechanically, so the element it feeds cannot release. The controller usually responds by forcing a failsafe or limp mode to protect the gearset. Typical repair costs on GMC range from $900 to $6,500, depending on the specific model and root cause.
Common Causes of P2818
- •Pressure control solenoid stuck open/on, or its valve-body bore worn so the valve will not return
- •Valve body wear, debris or varnish holding the control valve in position
- •Low, burnt, overheated or contaminated transmission fluid; clogged filter
- •Open, shorted or chafed solenoid wiring, or a corroded internal transmission connector / pass-through
- •Failed transmission control module or internal control solenoid assembly
- •Worn clutch material circulating debris through the hydraulic circuit
P2818 on GMC by Model
GMC Sierra 1500(1 issue)
- 10L80/10L90 10-Speed Valve Body Failure — Loss of Reverse, Limp Mode, and Year-Long Parts Backorder2024-2025
2024-2025 Sierra 1500 trucks with the 10-speed automatic (5.3L L84, 6.2L L87 and 3.0L Duramax LZ0) are failing at very low mileage with a stuck valve-body solenoid. Symptoms: a 'Service Transmission' or 'Service Transmission — Unable to Shift Soon' message, sudden hard/slamming shifts, slipping, complete loss of reverse (owners have had to push the truck out of parking spaces), and default limp operation limited to fifth gear and reverse. Several complaints report the failure occurring under 7,000 miles. NHTSA reports cite DTC P2818 (pressure control solenoid) and P0747/P0700. The situation is compounded by a national valve-body backorder — owners document 50-plus days and in some cases over a year waiting for the part, with GM sometimes authorizing a full transmission replacement instead. Complaint ODI numbers include 11756150, 11754176, 11748050, 11744152, 11739083, 11727368, 11721983, 11694617, 11684139, 11680422, 11680435, 11654431, 11644523, 11634982 (2024) and 11711937 (2025).
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View P2818 across all makes →Frequently Asked Questions
What does P2818 mean on GMC?▼
P2818 stands for "Pressure Control Solenoid "H" Stuck On." SAE-defined generic powertrain/transmission code. Transmission pressure control solenoids meter line pressure to the clutch and band circuits so the transmission can change ratio smoothly. The transmission control module commands solenoid "H" off and then checks the resulting pressure, gear ratio and slip. P2818 sets when the module sees the hydraulic circuit still pressurised — the solenoid is stuck in the applied (on) state, either electrically or mechanically, so the element it feeds cannot release. The controller usually responds by forcing a failsafe or limp mode to protect the gearset. On GMC specifically, this code is documented across 1 model.
What causes P2818 on GMC vehicles?▼
Common causes on GMC: Pressure control solenoid stuck open/on, or its valve-body bore worn so the valve will not return, Valve body wear, debris or varnish holding the control valve in position, Low, burnt, overheated or contaminated transmission fluid; clogged filter, Open, shorted or chafed solenoid wiring, or a corroded internal transmission connector / pass-through, Failed transmission control module or internal control solenoid assembly. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2818 on a GMC?▼
Repair costs on GMC range from $900 to $6,500, depending on the specific model and root cause.
Which GMC models have P2818 documented?▼
Au7o has documented P2818 on 1 GMC model: Sierra 1500.