P2824: T93 default-disable valve open-circuit detection

In the cited GM table, P2824 is expressly limited to the T93 controller and the ten-speed default-disable control circuit. The generic pressure-control-solenoid-J label conceals that useful restriction. This monitor evaluates electrical voltage behavior associated with an open circuit; it does not directly test whether the valve moves hydraulically.

How the decision is qualified

The controller's open-circuit classification corresponds to very high circuit impedance, listed above 200 kilohms. That is a controller fault criterion, not permission to apply a resistance test to a connected powered module. The table accumulates more than 0.30 seconds of failure during a sample longer than 0.50 seconds, with a 6.25-millisecond update interval.

The assigned high-side driver must be on. Battery voltage must exceed 9 volts and remain below 32 volts, and the calibration must enable the monitor. Thus, an ignition-off continuity observation and the actual powered diagnostic are different pieces of evidence.

Useful next decisions

First establish that the vehicle actually has the documented T93 arrangement. Next determine whether the circuit fails when the relevant driver is enabled; an inactive supply can make an otherwise intact circuit appear electrically absent if the measurement is interpreted without its operating state. Use controller-specific service information to separate a disconnected load, interrupted wiring and internal driver behavior.

A successful verification should include a completed open-circuit monitor with normal driver operation. Merely clearing the code or observing normal gear engagement does not demonstrate that this particular electrical path now satisfies its diagnostic.

Source and applicability

Documented 2025 GM gm-2025-04b monitor only; vehicle, engine and controller applicability must be established separately. GM monitor table, PDF page 2312.