1
Intermittent bulb warning Mon Oct 17, 2016 2:21 pm
Bikesmith
![Bikesmith](https://2img.net/u/4211/29/48/93/avatars/4479-75.jpg)
Silver member
![Silver member Silver member](https://i.servimg.com/u/f80/11/71/56/74/bmw-2s10.gif)
Hey everyone!
I (think I) fixed my problem!
The entire time I've had my 1985 K100rs, my bulb warning light has been coming on intermittently. I'd occasionally go 300 miles without seeing it. More commonly, it was every 5 miles. A tap of the brake lever would always turn the light off, but it always came back.
I tried all the usual things; I replaced all light bulbs, cleaned and deoxited all connections. Nothing worked. Yesterday, I finally pulled the Bulb Monitoring Unit out and opened it up. At three of the joints between the connector blades and the circuit board, the solder had cracked. The blades were wiggling freely. Seeing that made me surprised the BMU was working at all.
After re-soldering all the joints (including the ones that still seemed good), I took the bike out for a quick 50 miles. No warning light
Of course, the problem might not actually be fixed. The warning light could still come back at any time. But I really think I got it this time.
I figured I'd post this message since I can't imagine I'm the only one with this issue. Hopefully, someone else can benefit from my trial and error.
-Jon
I (think I) fixed my problem!
The entire time I've had my 1985 K100rs, my bulb warning light has been coming on intermittently. I'd occasionally go 300 miles without seeing it. More commonly, it was every 5 miles. A tap of the brake lever would always turn the light off, but it always came back.
I tried all the usual things; I replaced all light bulbs, cleaned and deoxited all connections. Nothing worked. Yesterday, I finally pulled the Bulb Monitoring Unit out and opened it up. At three of the joints between the connector blades and the circuit board, the solder had cracked. The blades were wiggling freely. Seeing that made me surprised the BMU was working at all.
After re-soldering all the joints (including the ones that still seemed good), I took the bike out for a quick 50 miles. No warning light
![cheers](https://2img.net/i/fa/i/smiles/icon_cheers.png)
Of course, the problem might not actually be fixed. The warning light could still come back at any time. But I really think I got it this time.
I figured I'd post this message since I can't imagine I'm the only one with this issue. Hopefully, someone else can benefit from my trial and error.
-Jon
__________________________________________________
Jon
Mechanically competent, electrically perplexed
------------------------------------
1985 BMW K100RS
1959 BMW R60
1942 Chevrolet 3/4-ton Special
1940 Royal Enfield WD/CO
1975 Porsche 911S