Measure the voltage between harness connector terminal and chassis ground.
Connector & terminal
4 door model
(B65) No. 1 (+) — Chassis ground (−):
5 door model
(B65) No. 3 (+) — Chassis ground (−):
Is the voltage 10 V or more?
• Check fuse No. 4 (in fuse & relay box).
• Check for open or short circuit in the harness between stop light & brake switch and fuse & relay box.