Parking Brake Switch Test

Turn ignition on. Inspect parking brake switch circuit on computer. Disconnect connector from computer. Check for 12 volts between terminal 12 (Celica, Cressida, Supra and Corolla) or 15 (Pickup, 4Runner and Van) of harness side of connector and ground. If yes, replace computer. If no, there is an open in harness between terminal 12 or 15 (as applicable) and parking brake switch. Inspect switch.