Weird Electrical Problem - BMW Forum

thekid · 10-29-2005, 01:55 PM

Yesterday I get in my car, turn it on and everything is reset, the radio is saying code, the OBC is stuck on Celcius and the clock says nothing but some dashes. So I set the clock, can't remember the radio code and drive to where I am going. I get back in the car, turn it on and everything is reset once again. WTF? So I start thinking about it, check the battery connections (even though the car could not start if the connections where that bad). So now I am thinking perhaps a fuse it blown? I called my friend/mechanic, he said he thinks it can only be a fuse (or something weird and worse), but at that time couldn't pull up a diagram for me to let me knwo which one(s) to check. Any one know which one(s) to check that could cause this? Or anyone have a better idea of where to start looking?

Michael Cornish · 10-30-2005, 01:54 AM

Had a similar problem with my e36
Was a fuse with a dry joint. Easiest way is to look in the fuse box under the bonnet (hood) and look at the legend.
One fuse will probably be common to all of your features not working. replace that fuse with a new one.
Hope this helps
regards
Michael

bad man working · 10-30-2005, 01:11 PM

Radio: fuse 9 & 44 = 20amp
OBC: fuse 23 = 5AMP F45 = 7.5amp

thekid · 10-30-2005, 05:36 PM

Thanks for the replies, but today it has gotten worse. Today when I turned the key, the gauges moved (like they normally do), then nothing happened. Then the car acted as though the battery was disconnected. So i went to the back, checked the connections, both were connected firmly. I pushed down on one of the connections and the car did the "key in ignition door open beep" once. Then no more, even though my key was in the ignition and the door was open. Then I got back in the car and started it. It started the first time, but the ilde was high, it held steady at abou 1.5k rpms. I tapped the gas, and it returned to 1.5k rpms. I drove the car around the parking lot to try and diagnos any other possibly symptoms related to the idle. The car drove fine, except for the high idle, so I parked it and borrowed a car.

I've still not gotten in to the fuses, because I don't have any extra fuses, I was going to get some while I was out today, but I ran out of time because of todays new car trouble.

thekid · 11-04-2005, 05:02 PM

Well i bought a multimeter and have checked the fuses. The fuses are fine and the multimeter reads above 13volts on the battery. The battery connectors look good, no corosion or anything like that... any other clues? Today the car started the first time no problem and the idle was rock steady in the appropriate range.

Gator · 11-05-2005, 10:26 AM

"I pushed down on one of the connections and the car did the "key in ignition door open beep" once." gives you a clue that the problem is in the battery or the connection that you pushed down. If everything was OK, nothing would have happened when you pushed. As always the first thing to suspect is the battery.
It probably has an intermittent internal short. Before you waste a lot of time troubleshooting, replace the battery with a known good one and see if the problem goes away.

thekid · 11-05-2005, 06:43 PM

This battery is a good one, it is not the battery. It may be a battery connector but both are corrosion free, or it may be the actual cable itself. At least one of those are what I am leaning towards right now.

BImmerN2B · 11-05-2005, 07:13 PM

Check Your Battery Cables Connections Because I Had A Problem Where The Car Would Start When It Wanted To. Then Took It To The Mechanic And All It Was Was The Battery Cables Connection That Was Loose.