P2818 code meaning
Pressure Control Solenoid H Stuck On
Powertrain system Generic code P28xx codes Check engine light
What P2818 means
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.
P2818 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 12 hours
- Clears after repairAfter a drive cycle
Symptoms of P2818
- 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
Common causes of P2818
- Most 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)
- Less likelyContaminated fluid holding the valve
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Pressure control solenoid hValve body
What each part of P2818 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 8 | Area: transmission. |
| 18 | The exact fault in that area. |
What to do next
- Note P2818 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2818
What does P2818 mean?
P2818 means "Pressure Control Solenoid H Stuck On". P2818 reports that valve H stays effective when it should be released. It is a generic code, so it means the same on every make.
Is it safe to drive with P2818?
Drive gently and only to a workshop. With P2818 the car can go into limp mode (reduced power) to protect itself.
Will P2818 fail an emissions test?
Yes, it can. P2818 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2818 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 12 hours of work. This is a job for a workshop.
Will P2818 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.