P0964

P0964 is the Pressure Control Solenoid B Control Circuit Range/Performance code — the electrical circuit ohms out fine but the hydraulic response does not match the commanded duty cycle within the expected band. PCS-B is the second linear/PWM pressure-control solenoid in the valve body (the first, PCS-A, sets main line pressure; PCS-B typically controls a clutch-apply circuit or a secondary regulator depending on platform). Cheapest-first: tap into the appropriate test port and connect a line-pressure gauge, then sweep the PCS-B duty cycle with a bidirectional scan tool while watching gauge response — a healthy linear PCS should produce smooth proportional pressure changes between roughly 50 and 260 psi depending on application. Stuck-high pressure with zero command means a stuck-closed solenoid or a sticking valve bore; stuck-low pressure with full command means a stuck-open solenoid, worn pump, or excessive internal leakage. Bench-ohm the solenoid against spec — most PCS-B units land 8-30 ohms cold (3-7 ohms for GM force-motor designs, 4-6 ohms for Toyota/Chrysler linear PCs, 5-12 ohms for Aisin). Then check ohms-to-ground on each pin (should be >100k ohms to case) and pin-to-pin for the solenoid itself; a low pin-to-ground reading with normal pin-to-pin resistance means ATF migration has shorted the winding to the case. Active driver current at full duty should land 0.5-1.5 A — anything below 0.3 A or pegged at 2 A points at the TCM driver or wiring, not the solenoid. Expensive-misdiagnosis caveat: on Chrysler 545RFE/68RFE the entire solenoid pack is a sealed integrated assembly with PCS-A, PCS-B, and all on/off shift solenoids on one body, and internal cross-leakage between adjacent solenoid bores frequently presents as a clean P0964 (or P0965/P0966/P0967) when the real fix is full solenoid-pack replacement — replacing just the PCS-B circuit-side wiring or the valve body separator plate will not catch a pack that's bleeding internally.

Vehicle-specific patterns: 1996-2007 GM 4L60E/4L65E in the Silverado/Tahoe/Trailblazer line throws P0964 (or the older equivalent P1870/P0776) when the 2-3 shift solenoid wears or the pressure-regulator boost valve bore eats itself — Sonnax oversized boost-valve kit is the standard fix, $80-200 in parts plus pan-drop labor. 2003-2010 Dodge Ram 1500/2500 with the 545RFE and 2007-onward 68RFE see P0964 routinely between 70,000 and 150,000 miles as the integrated solenoid pack degrades; per AAMCO and RepairPal aggregated cost data, RAM 545RFE/68RFE solenoid-pack replacement runs $500-900 parts plus labor at independents, and Chrysler dealer quotes typically land $1,000-1,400 all-in. 2007-2013 Dodge/RAM 6.7 Cummins with the Aisin AS69RC sets P0964 from PCS-B contamination after a failed deep service or torque-converter shudder dumping debris into the pack — Aisin solenoid replacement requires valve-body R&R, $800-1,400. 2001-2010 Chevy/GMC HD with the Allison 1000 throws the LCT1000 equivalent from PCS-2/PCS-3 chafing where the internal harness crosses the case-flange ridge, a known wiring fix before solenoid replacement. Estimated repair: $300 to $1,500.