4. Check Stop Lamp Switch Input Signal Circuit For Open And Short

1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 2.

   Refer to WIRING DIAGRAM.

   1. Continuity should exist. 
4. Also check harness for short to ground and short to power.

OK or NG 

1. OK: GO TO 6 .
2. NG: GO TO 5.