Drivers who encounter a P0752 code usually notice the transmission behaving erratically before the check‑engine light illuminates. The most common cues are:
These signs appear because Shift Solenoid A remains energized, forcing the hydraulic circuit to stay in the “on” position. The result is a mismatch between the driver’s torque request and the gear that the transmission actually selects.
The TCM commands each shift solenoid with a pulse‑width‑modulated (PWM) signal. If the TCM’s output driver for Solenoid A is shorted or its firmware has corrupted timing tables, the module may continuously send a “high” signal, producing the “stuck‑on” condition.
Corrosion, broken pins, or a short to ground in the harness that runs from the TCM to the solenoid can hold the circuit at voltage. A damaged connector seal can also allow moisture intrusion, creating intermittent “stuck‑on” readings that trigger P0752.
Although the solenoid itself is a mechanical component, its internal coil can develop an insulation failure that effectively shorts the coil to the power rail. In that case the TCM’s command is irrelevant—the solenoid will stay energized regardless of the signal.
Manufacturers sometimes release transmission calibration updates. If a vehicle’s software version is mismatched with the TCM’s hardware revision, the control algorithm may misinterpret sensor data and keep Solenoid A energized as a protective measure.
*While a faulty solenoid could cause the symptom, the issue may stem from the TCM not communicating correctly with the transmission. A diagnostic scan and module communication test will determine if module replacement or reprogramming is needed.*
Connect a professional OBD‑II scanner, read the P0752, and note any related codes (e.g., P0700, P0753). Clear the codes and perform a test drive to confirm recurrence.
Using a multimeter, measure voltage at the solenoid connector with the ignition on. A constant 12 V indicates a stuck power feed; a fluctuating reading suggests a wiring issue.
Many scan tools include a “TCM Output Test” that toggles solenoid signals while monitoring vehicle response. If the tool cannot command the solenoid off, the TCM’s output driver is suspect.
Visually examine the harness for frayed wires, corrosion, or loose pins. Perform a continuity check from the TCM pin to the solenoid connector. Replace damaged sections or clean corroded contacts.
If the vehicle’s service information lists a transmission control software revision newer than the one installed, flash the updated calibration to the TCM. This can resolve timing‑related “stuck‑on” conditions.
If the TCM output and wiring are confirmed functional, bench‑test the solenoid by applying 12 V directly. A solenoid that remains energized confirms internal failure and should be replaced. However, the primary repair focus remains on the control module.
When the TCM fails the output test or shows internal faults, re‑programming with the latest factory calibration often restores proper control. If the module’s hardware is damaged, replacement is the reliable solution.
Cost estimates
If the TCM repeatedly fails output tests after wiring verification, or if the module shows internal board damage (burn marks, corrosion, or moisture intrusion), replacement is the most dependable path. Repairing a compromised circuit board may provide a temporary fix, but the underlying failure often recurs, leading to additional transmission wear.
Modern control modules are complex and integrated with vehicle security and immobilizer systems. That’s why choosing a replacement isn’t only about the hardware—it’s about correct programming and compatibility. Flagship One specializes in VIN‑matched control modules, providing a plug‑and‑drive solution backed by warranty. Replacement units vary depending on production date and software version, so the correct module is matched by VIN before programming, ensuring seamless integration with your vehicle’s existing networks.
Service Recommendation: Most issues related to this fault are diagnosed and corrected through inspection, wiring repair, and calibration rather than module replacement. For modules not typically replaced through aftermarket suppliers, diagnosis and repair should be performed by a certified automotive technician with access to factory service information and tooling.