Diagnosing intermittent fog light failure

[Jimmy2Time]

Last spring, I rewired my 99 R1100RTP’s right handle bar light switch back to the original euro mode (On/Parking/Off). I used Woodie’s posts to help me through this process.

During the same time, I installed some fog lights and mounted them to the crash bars. I used the auxiliary power that runs into the glove box that used to power the extra police battery for the main power to run the lights and I tapped into the parking light as the trigger source. I used one of the police switches on the handlebar to turn them on/off. This was the same police switch that used to turn on and off all the lights (headlight & parking light) before I rewired the right handlebar.

 

Everything has worked fine up until about a week ago. Road to work, fog lights worked. When I started up the bike for the trip home, the fog lights wouldn’t work. I checked the police fuses and they all look fine. All the other lights are working as normal.

Yesterday, same thing happened, fog lights turned on in the morning but for my return trip home, they didn’t.

 

Needless to say, I’m confused. I was thinking that it could be the switch but at this point I’m just guessing.

 

I really could use some solid advice on how to track down this problem.

 

I’m not an electrical genius. I have a multi-meter and I tested the line coming from the switch, but it seemed backwards. I got a reading when the bike was on but the switch was set to off. When I turned the switch to the on position, I didn’t get a reading anymore.

 

Any advice is appreciated. Thanks in advance.

[KevinH]

Clean the switches. Grime and water play havoc with the contacts.