Powertrain, generic (extended)

P27AA Pressure Control Solenoid D Data Incompatible

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modePossible

P27AA is set when the TCM finds the calibration block for pressure control solenoid D unusable. Which hardware that is depends on the gearbox: GM's 2016 eight-speed assigns D to clutch 4 (C23468), while the 2017-2020 tables put the nine-speed's C2 clutch (CB29), the ten-speed's C5 clutch and the CVT's C1 clutch behind the same letter, so the D used by stuck-off code P2714 is not always the same part. GM checks it once at start-up, Type A. Ford handles the same task differently: its 10R60/10R80 summary reports a bad or empty TRID block holding solenoid data under its own codes P163E and P163F. Reprogramming the data that belong to the fitted valve body clears the fault.

Likely causes

Solenoid data not loaded after a transmission or TCM repair

Used TCM from another vehicle still carrying its old valve body data

Wrong valve body part number used for the download

Symptoms

MIL and stored DTC at key-on
Rough shifts into gears using the clutch behind valve D

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€100–400

Time0.5–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

pressure control solenoid dtcm

References: law.cornell.edu, gsi.ext.gm.com, gsi.ext.gm.com, fordservicecontent.com.