P2717

P2717 narrows the P2716 family fault to a specific failure mode: Pressure Control Solenoid D control circuit LOW — the TCM driver is seeing the solenoid command line pulled to ground or near-ground when it should be cycling between 0V and battery voltage under PWM control. The fault modes are: the solenoid coil is internally shorted to ground (the coil winding has bridged to the solenoid case), the harness wire from the TCM driver pin to the solenoid is shorted to chassis ground somewhere between the connector and the solenoid (often where the lead-frame passes through the case connector), or the TCM driver itself has failed shorted-low on that channel (rare but possible on high-mileage TCMs that have run through repeated solenoid coil shorts that took out the driver). Cheapest-first ladder: with the solenoid disconnected at the case connector, key-on, measure resistance from the solenoid driver pin to ground — anything below the coil's spec resistance (8-30 ohms typical for PCS-D) measured between the TCM pin and ground with the solenoid disconnected indicates a wiring-to-ground short, NOT a solenoid; with the harness disconnected from the TCM and from the solenoid, isolate the solenoid-side resistance (8-30 ohms coil-to-coil, infinite resistance coil-to-case-ground — anything less than infinite to the solenoid case is a shorted coil); back-probe the TCM driver pin with the harness reconnected and scope the PWM waveform during a commanded lockup — a healthy driver pulses 0V to 12V at the commanded duty cycle, a stuck-low driver sits at 0V. Before condemning the TCM on a P2717, ALWAYS isolate the solenoid coil itself (drop the pan and check coil-to-case resistance) — a coil that's shorted internally to its own case will take out the TCM driver on the next drive cycle if not replaced, so condemning the TCM first wastes the money and leaves the root cause in the trans.

Vehicle-specific patterns: 2011-2017 Ford F-150/Expedition/Mustang 6R80 is the dominant P2717 platform — the TCC PCS coil ages and develops an internal short to case ground, which then takes out the TCM driver on the same channel if not caught early; Ford issued service updates on early 6R80 solenoid replacement and on TCM replacement when the driver is confirmed failed. 2013-2018 Ram 2500/3500 with the Aisin AS69RC throws P2717 from internal lead-frame chafe in the trans pan where the lead-frame routes over the valve body — the chafe shorts the PCS-D circuit to case ground. 2008-2014 GM 6L80/6L90 throws P2717 from internal wiring harness pin-fret and from the PCS coil shorting to ground on high-mileage trucks. 2009-2014 Chrysler 545RFE/65RFE family throws P2717 from solenoid pack internal failure. 2007-2013 BMW ZF6HP and ZF8HP-equipped models throw P2717-class codes from mechatronic-unit internal failure (the mechatronic is the integrated TCM + solenoid pack; the failure is usually internal solder-joint fatigue on the TCM substrate). Estimated repair: $250 to $1,800.