P2818Pressure Control Solenoid H Stuck On
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2818 reports that valve H stays effective when it should be released. In GM's eight-speed table for the 8L90, H is the default valve: in Park at 400-900 rpm, with fluid between 0 and 40 °C and a converter clutch test pressure of 600 kPa, slip of 6 rpm or less for 0.5 s counts as a fail, and the MIL follows after two trips. Bulletin PI1405 repeats cold starts in that range and replaces the gearbox if the code returns; 15-07-30-002 instead reprograms the module against firm 1-2 and 3-1 shifts with P0606 or P2818. On the ten-speed H is the converter clutch valve; GM bulletin 24-NA-230 links a stuck-on clutch on 2024-2025 Silverado and Sierra 1500 to the engine stalling when D or R is selected, mostly due to the valve body.
- What you may notice
- Engine stalls when coming to a stop or when D or R is selected
- Firm upshifts or downshifts, shudder
- MIL on, code may set only at low fluid temperature
- Likely causes
- LikelyValve in the valve body sticking in the applied position
- PossibleEarly TCM calibration (GM 8L90 2015, reprogramming)
- PossibleInternal transmission fault that persists when cold (PI1405)
- RareContaminated fluid holding the valve
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.