electrical and ignition #8 Fuse Problems

[Doug Riparetti]

#8 fuse blew-up on the drive home Saturday. I‘ve only own the car (1975) for a couple of months, that was the 1^st time driving in the rain. Not that the rain is/was the problem, but that was the deciding factor that has been different from the 2500 miles I’ve racked-up on the car since I purchased it.

 

After the Saturday drive, the right rear taillight does not work (it's not the bulb, I tried that), and the gauge cluster night-lights do not work. Prior to that, all electrical was in working order, (brakes lights, gauge cluster etc…..)  It popped the original fuse that was installed, plus two more, any thoughts of what went wrong?

 

Thanks

[esty]

https://www.google.com/search?q=site%3Abmw2002faq.com+%238+fuse+blew&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

[eurotrash]

spin the fuses with your finger a few times every now and then.  to insure good contact.

[Mike87]

I had an issue similar to yours many years ago. Turned out to be the backup light wiring at the transmission. One of the wires was pinched and kept grounding causing the fuse to blow. It would only do it on right hand turns. It was a nightmare to find, but once I found and corrected the problem, the issue has not returned.

[Doug Riparetti]

@Eurotrash

 

It's not a contact problem at the fuse box. I'm bringing to a buddy in a bit, to see WTF is going on

[FunkyLaneO]

You obviously have a short somewhere, maybe it is caused by water bridging an uninsulated spot of wire, who knows. you need to get a wiring diagram and trace out all the wires on that circuit and see if you can find the culprit.  If you don't want to waste a bunch of fuses testing you can take an old sealed beam headlamp and wire it in place of your fuse, it will light up every time the system shorts so you can watch the light while you unplug and wiggle things to isolate the short.

 

Here is an article that explains the sealed beam trick: http://www.crookedriverwriter.com/index.php?option=com_content&view=article&id=71:find-electrical-shorts-faster&catid=22&Itemid=235

[Doug Riparetti]

Found the problem. During my gauge cluster re-hab, the wire that attaches to the tack, was not properly pushed on to the terminal, and it fell off. It's been about 6-weeks since that that tasked was performed, I guess it took a while for it to fall off. Re-installed it, and everything is back to normal. Thanks for the help

[FunkyLaneO]

The signal wire falling off the tach wouldn't cause what you described so I am guessing you wiggled or reconnected something else under there that inadvertently fixed it.  Worst case scenario with the signal wire would be if it grounded out your car would stop running because it would no longer receive a valid signal from your distributor but no fuses would blow unless it touched an uninsulated hot circuit which there should not be behind your tach.

[Doug Riparetti]

I replaced the headlight switch that I picked up at a junk yard for 10 bucks, that cured the #8 fuse blowing problem, (gauge cluster lights, right rear taillight and right front parking light functioning PERFECT)