Pressure Control Solenoid "B" Control Circuit/Open
The transmission control module has detected an open or shorted circuit in the Solenoid B control circuit, which regulates transmission fluid pressure. This solenoid controls fluid flow during specific gear changes and transmission operation, and when it malfunctions, the transmission enters limp mode to prevent damage.
What You Might Notice
- Check Engine Light activated
- Transmission slips when shifting
- Transmission shifts hard or bangs into gear
- Increased fuel consumption
- Transmission overheats
Most Common Causes
- 1
Solenoid B electrical connector issue
The connector to the Solenoid B may be loose, corroded, or damaged, preventing proper electrical communication. Check for corrosion, bent pins, or loose connections at the solenoid connector.
- 2
Wiring harness damage
The wiring to Solenoid B may be cut, frayed, or broken, creating an open circuit. Inspect the transmission harness for visible damage, pinched wires, or rodent damage.
- 3
Solenoid B failure
The Solenoid B coil may have an internal open or winding failure, preventing it from receiving and responding to electrical signals. This requires solenoid replacement.
- 4
Transmission control module issue
The PCM or transmission control module may have a faulty output driver or internal circuit problem preventing it from sending voltage to the solenoid. This is less common but possible.
How to Diagnose It
- 1
Check Solenoid B electrical connector issue — The connector to the Solenoid B may be loose, corroded, or damaged, preventing proper electrical communication. Check for corrosion, bent pins, or loose connections at the solenoid connector.
- 2
Check Wiring harness damage — The wiring to Solenoid B may be cut, frayed, or broken, creating an open circuit. Inspect the transmission harness for visible damage, pinched wires, or rodent damage.
- 3
Check Solenoid B failure — The Solenoid B coil may have an internal open or winding failure, preventing it from receiving and responding to electrical signals. This requires solenoid replacement.
- 4
Check Transmission control module issue — The PCM or transmission control module may have a faulty output driver or internal circuit problem preventing it from sending voltage to the solenoid. This is less common but possible.
How to Fix It
- 1
Inspect and clean solenoid connector
Locate the Solenoid B connector, disconnect it, and inspect for corrosion or damage. Clean the connector pins with electrical contact cleaner and dielectric grease, then reconnect firmly.
- 2
Check and repair wiring harness
Trace the solenoid B wiring harness from the connector to the control module. Look for cuts, abrasions, or pinches. Repair damaged wires with proper splicing and heat shrink tubing or replace the harness section.
- 3
Replace Solenoid B
If connector and wiring are intact, remove the old solenoid and install a new or rebuilt Solenoid B unit. Ensure proper seating and torque specifications are followed.
- 4
Verify transmission control module function
If solenoid and wiring are good, use a multimeter to test voltage output from the transmission control module to the solenoid circuit. If no voltage is present, the PCM may require reprogramming or replacement.
Need a deeper diagnosis?
Search for related repair guides or browse by system.