• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

Electrical Problem....feedback/suggestions will be Appreciated

mwctexas

New member
Hello Forum Members....I've sought help from the forum several time....and received excellent information....
Well...I've got an issue with my 1974 R90/6
Started and warmed it up for 2 minutes or so, cut it off...ran fine...Went to get on and leave....switch on...nothing but headlight and tail light...no cluster, no starter, no brake lights, turn signals or horn. Battery connections are fine.
Fooled around with the shift lever...juggled oil pressure switch/Trans switch wires..cluster lights were intermittent. Finally they stayed on...started up and rode off...concerned.
While riding no horn, turn signals and when I'd tap either brake...the generator light pops on, bright red.
Got home, cut it off, 30 minutes later hopped on, would not start.
Hopefully this is something you can pass along your thoughts and or suggestions.
I appreciate your help and taking the time to read this.
Thank you very much!!...Mike
 
9 times out of 10 it's the battery. How old is the battery? Can you get it load tested? One way of load testing is to put a voltmeter across the battery terminals and what the readings as you hit the starter. Voltage should not drop below 10 or so...more than that would indicate a bad battery.

Could also be your starter relay. Corrosion on the terminals. Find it under the tank on the left side...unplug and replug several times to help scrape some of the corrosion away.

But I'd see about getting the battery a good load test.
 
Battery Tested..

Thanks for the info. It's a 3 month old AGM. Load tested. With ignition on, no cluster lights, no starter. If I apply brakes or hit starter button, no change in battery voltage.
 
Guess it's starter relay next. Definitely check connections...the easy stuff.
 
Problem fixed!

Thanks for all the replies!.....Using the feedback I replaced what was obviously the original starter relay....It needed replacing regardless...
That didn't do it. So again based on the feedback I was going to replace the ignition switch...but, after disconnecting/reconnecting the connectors on it..
Problem solved!..I may replace it anyway, hopefully I can find an original switch and replace it. They aren't avail new.
Thanks again for the help. Much obliged. Mike..
 
I have found that a shot of WD-40 on connections- or switches from time to time helps with problems like you described.
OM
 
Back
Top