Code 10, Stoplight Switch On Constantly
- Apply parking brake. Turn ignition on. Observe brake lights. If brake lights are on, replace stoplight switch.
- Turn ignition off. Disconnect RWAL ECM connector. Measure voltage between ECM terminal No. 8 and ground. See Figure. If reading is less than 10 volts, repair open in Green/White wire between stoplight switch and RWAL ECM. If reading is 10-15 volts, replace RWAL ECM.