Kind of broken brake light

[jakub7]

So I have a 03 xb9 and my brake light works partially. As in the front doesn't activate the brake light at all and the rear only activates when I apply ALOT of force. So even if it is the front switch, that doesn't explain the rear. I checked all wiring and all looked fine. Its led if that makes a difference. I searched the forum and all over the internet with no answer.

[user_deleted]

your 2003 XB uses a front nissin switch unique to that year and only fits 2003 XB and the 2000-2002 tuber models. it has the wide-spaced spade terminals. as with any other electrical switch they can fail. properly test it by removing the 2 wire plugs exposing the blade terminals...get an ohm meter...attaching the ohm leads one to each blade...and activating the brake lever. you should hear a light "click" and see the ohm-meter reveal the same reading to you as it would if you touch the ohm-meter leads together. the rear brake light switch is activated by pressure generated within the master cylinder. it is a pressure style switch. if sporadic in operation you can remove it and try to thoroughly clean the inner workings...and also check the little harness that goes up to the under seat area and plugs into main harness. that plug does occasionally corrode and a good cleaning solves it. if these 2 things don't resolve the problem the switch is at fault.
2003 XB front switch fits that year XB only. part # Y0820.9 also crosses over to honda part # 35340-MM5-600

[Cooter]

Lunatic is on top of it as usual

A good easy cheat to check the entire brake light electrical circuit (work for both the front and the rear) is to remove the 2 terminals at the switch and with the key on, touch them together. The brake light should turn on. If it doesn't, it's the switch or the bulb.

[neilrl79]

The front brake light switch on my 03 failed. I removed it, opened it up and used a wire brush wheel on a Dremel to clean the contacts, put it back together and reinstalled.... Worked perfect from there on out.