P0964
Pressure Control Solenoid B Control Circuit / Open
Powertrain Transmission Control Transmission Solenoid Circuit 🟡 Moderate — Fix within a week
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What This Actually Means
In plain language — no jargon

The engine control unit detected a break or poor connection in the electrical circuit controlling the pressure solenoid for transmission fluid. Think of it like a light switch that's either loose or broken—the power can't reach the solenoid to function properly.

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Symptoms You May Notice
3 known symptoms for this code
Transmission shifting delays or harsh shifts
Check Engine Light illuminated
Transmission limp mode or reduced power
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECM monitors voltage and current draw through the pressure control solenoid B circuit. It detects opens (broken connections) or shorts by checking if expected voltage appears at the solenoid coil during commanded cycles. When resistance exceeds normal thresholds or voltage fails to reach the solenoid, the fault is triggered.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Solenoid Circuit Voltage 11.5-14.5V when commanded active 0V or missing signal / open circuit detected
Solenoid Coil Resistance 5-15 ohms (varies by solenoid) Infinite resistance (open) or critically high
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Wiring harness and connectors
Inspect the solenoid B connector for corrosion, loose pins, or damaged wires; clean or reseat connections.
2
Solenoid B electrical connector
Disconnect and reconnect the pressure control solenoid B plug to remove oxidation and ensure firm contact.
3
Pressure Control Solenoid B
Replace the solenoid if resistance tests show an open or if wiring repairs do not resolve the fault.