FixVault

Transmission Control Indicator Light

  1. 1) Check Transmission Control Indicator Light (TCIL)

    Turn ignition on. If TCIL is flashing, perform QUICK TEST procedures in SELF-DIAGNOSTICS - 7.3L DIESEL article. If any DTCs are present, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 7.3L DIESEL article and perform appropriate SYSTEM TESTS. If no DTCs are present, go to next step.
  2. 2) Check TCIL Symptom

    Toggle Transmission Control Switch (TCS) on and off several times to operate TCIL. If TCIL remains on, or remains off with TCS operation, go to appropriate symptom under SYMPTOM DIAGNOSIS under TROUBLE SHOOTING in appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. If TCIL goes on and off with TCS operation, TCIL is okay.