P2727: Solenoid E circuit is electrically open in the selected transmission

P2727 identifies an open control circuit for pressure-control solenoid E in the reviewed GM monitor. The component mapping varies: the source names 9-speed C57R, 10-speed C1356789, 8-speed C45678R, or the CVT torque-converter-control solenoid.

Circuit identity comes before a parts decision

The same code letter therefore can refer to a clutch-control function in one transmission and converter control in another. Confirm the installed transmission and its mapping rather than using the generic label to choose a component.

The controller detects voltage outside its permitted circuit range. The stated open-circuit design specification is impedance above 200 kilohms between signal and controller ground. Failure must exceed 0.30 second in a sample period exceeding 0.50 second, with a 6.25-millisecond update.

Confirm the powered test context

Battery voltage must be above 9 V and below 32 V for more than one second. An applicable run/crank, accessory or accessory-power-mode condition must be satisfied, and the assigned high-side driver must be on.

An unpowered solenoid path is not automatically an open-circuit failure. Knowing whether the supply driver was enabled changes how a voltage observation should be interpreted. The impedance limit is not a live-circuit resistance-testing instruction.

Verification should establish an intact correctly identified control path and a completed monitor without recurrence. P2727 does not prove that the associated clutch is mechanically failed or that the solenoid itself needs replacement. The documented response is Type A, one trip.

Source and applicability

Keep the stated transmission function and source calibration separate from other applications. GM diagnostic table, PDF page 1182.