P0976
Shift Solenoid B Control Circuit Low
Powertrain Transmission Control Solenoid Control Circuit 🟡 Moderate — Fix within a week
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What This Actually Means
In plain language — no jargon

The transmission control computer detects that Shift Solenoid B isn't receiving enough electrical power to operate properly. It's like a light switch that's not getting enough current to turn the light on.

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Symptoms You May Notice
3 known symptoms for this code
Transmission stuck in limp mode or default gear
Harsh or delayed gear shifts
Check Engine Light illuminated
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECM monitors the voltage and current flowing through Shift Solenoid B's control circuit. When voltage drops below the minimum threshold needed to activate the solenoid coil, the ECU logs a fault. The circuit typically operates at 12V, and a significant voltage drop indicates resistance, wiring issues, or a failing solenoid.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Solenoid Control Voltage 11-14V with proper current draw Below 10V or insufficient current when commanded on
Circuit Resistance 4-8 ohms coil resistance Above 15 ohms or open circuit detected
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Battery and connections
Clean corrosion from battery terminals and check battery voltage is above 12.6V at rest.
2
Solenoid wiring harness
Inspect wires for cuts, corrosion, or loose connectors at Shift Solenoid B and transmission control module.
3
Shift Solenoid B
Test resistance with multimeter; replace solenoid if resistance is out of specification or circuit remains open.