P0955 — Auto Shift Manual Mode Circuit

P0955: Concerns the circuit for manual shifting mode in an automatic transmission.

Meaning, symptoms, causes and checks

Concerns the circuit for manual shifting mode in an automatic transmission. The verified definition does not describe a general Sport, Winter or performance-mode selector.

Affected system: Automatic/manual shift control (ASM)

Symptoms

  • Warning light may illuminate
  • Related system function may be impaired
  • Vehicle-specific symptoms vary

Possible causes

  • Transmission fluid, hydraulic, solenoid, connector, or control-circuit issue
  • Related wiring, connector, power or ground fault
  • Vehicle-specific mechanical or control issue

What to check

  • Record stored and pending codes and freeze-frame data
  • Compare commanded and actual transmission data, inspect fluid condition and level according to the vehicle procedure, then test the relevant circuit and solenoid.
  • Confirm measured values against the vehicle service information
  • Retest under the conditions that set the code
  • Compare commanded and actual transmission data, inspect fluid condition and level according to the vehicle procedure, then test the relevant circuit and solenoid.
  • Repair the verified cause and confirm the code does not return

Also written as: P0955-00, P095500, PO955 (some scan tools add the fault-type byte, e.g. -00).