P1850 — Chevrolet — Brake Band Apply Solenoid Circuit

P1850 (Chevrolet): Brake Band Apply Solenoid Circuit — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Brake Band Apply Solenoid Circuit. Source catalogue definition; confirm applicability using vehicle service information.

Affected system: Powertrain

Symptoms

  • Check Engine Light illuminated
  • Transmission shifting harshness or slipping
  • Inability to engage specific gears
  • Transmission stuck in limp mode

Possible causes

  • Faulty brake band apply solenoid
  • Open or short circuit in the solenoid wiring harness
  • Corroded or loose electrical connectors at the transmission
  • Failed Transmission Control Module (TCM)
  • Low or contaminated transmission fluid interfering with hydraulic pressure

What to check

  • Inspect the transmission wiring harness for physical damage or burnt insulation
  • Check all electrical connectors for corrosion and ensure secure seating
  • Measure the resistance of the brake band apply solenoid using a multimeter
  • Verify the transmission fluid level and condition for signs of debris
  • Perform a scan tool actuator test to confirm solenoid operation