P27AE code meaning
Pressure Control Solenoid H Data Incompatible
Powertrain system Generic code P27xx codes Check engine light
What P27AE means
P27AE is the highest letter GM publicly checks for characterization data. It is absent from the 2016 eight-speed table and first appears in 17OBDG04, where H stands for the nine-speed's C6 clutch (C6789) and the ten-speed's torque converter clutch; 20OBDG04 adds mode valve B on CVTs with electronic range select. The test is identical to its siblings: one pass at TCM initialization, failure if the data are absent, of another device class, fail their checksum or show decreasing axis points, then Type A after one trip. On a ten-speed, wrong data for H mainly shows up as poor or shuddering lock-up. Since only the data are at fault, a dealer-level download, not a mechanical repair, normally ends it.
P27AE at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 1.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P27AE
- MIL on
- Shudder or missing converter lock-up on ten-speed units
- Higher fuel consumption if lock-up is suppressed
Common causes of P27AE
- Most likelyReplacement TCM delivered blank and not set up with valve body data
- PossibleValve body or solenoid service without data update
- Less likelyCorrupted solenoid H data block
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Pressure control solenoid hTCM
What each part of P27AE means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 7 | Area: transmission. |
| AE | The exact fault in that area. |
What to do next
- Note P27AE 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 P27AE
What does P27AE mean?
P27AE means "Pressure Control Solenoid H Data Incompatible". P27AE is the highest letter GM publicly checks for characterization data. It is a generic code, so it means the same on every make.
Is it safe to drive with P27AE?
Drive gently and only to a workshop. With P27AE the car can go into limp mode (reduced power) to protect itself.
Will P27AE fail an emissions test?
Yes, it can. P27AE 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 P27AE to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 1.5 hours of work. This is a job for a workshop.
Will P27AE clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.