Cluster Capacitor Replacement - Question

[BMWDriver]

Well, I found the culprit. It's a 1000µF, 16V, 105 degrees Farenheit (or is it Celcius ?) capacitor which leaked.

It's causing the fuel gauge to show empty when half full or less, and shows the "Oil Low" message repeatedly, though there is enough. The fuel gauge had been somewhat inaccurate for awhile before anyway.

My question is: would a below 105 deg. F capacitor do to replace ? Last time I went shopping for a capacitor was for a 45µF at 95 degrees, but found 85 to be the highest available.

I'll post pictures of my repair and of the leaky thing later this week, maybe tomorrow.

[gale]

Get the 105 C caps, the inside of the car can get smokin hot in the summer, especially the dash if it's in the sun.

Try Allied:

www.alliedelec.com

put "capacitor electrolytic radial" in the search.

[BMWDriver]

Thanks for the info. I'll do my best.

Looking at the head unit I pulled out, and took apart, I found 1000µF capacitors at 16V, exactly what I need, except they rate at 85 C. 105C is beyond boiling point, and I should wonder if that is ever reached inside a car. But, when soldering... maybe that's the issue here.

I'll go shopping tomorrow at The Source, and cross my fingers to find what I need.

[bones]

hey driver, glad to see you are going after that cluster also.ive got a 1989 525I 240,000 miles.i replaced 9 caps on the board and bought them all at radio shack.they were the 105's.but i exceeded the voltage and microfarad rating on all but a couple and the cluster works flawlessly.even fuel quanity is stable and seems to be accurate.i also flowed all solder joints on all the connectors from the harnesses to the board,i know this made a difference especially on the connector that houses the coding chip.your soldering iron should have a tip no bigger than a well sharpened pencil.this will limit the amount of heat transfered to the component and the pcb. good luck.bones

[Blitzkrieg Bob]

I was able to find all of them at Digikey.com

[BMWDriver]

Thanks for the feedback. Well, Radio Shacky (now The Source in Canada - they got bought) is getting out of capacitors it seems, and all these types of part. They hardly carry them anymore. However, there is a spot here in Montreal called Addison Electronique which carries all kinds of electronic parts; a real dream place for electronic enthusiasts. They're just out of my way and closed on Sundays.

So, I've replaced the biggie with an 85 C capacitor. Checking on the bmwe34.net, the advice is that this should pose no problem. I've also done research on capacitors (Wikipedia and linked pages) and it relates to the environment temperature it can withstand.

That was the finest soldering job I've ever done, and it's nice. I don't have a pic, they're at home. I'm waiting to see how it goes when my fuel gauge reaches half. I might decide to replace all capacitors in the end, nevertheless. Maybe next week.

[Blitzkrieg Bob]

finding 105 caps locally, so I just ordered them from Digikey for a few $.

[BMWDriver]

finding 105 caps locally, so I just ordered them from Digikey for a few $.

Are you doing the blue cluster ? Could you list the caps if so ? That would save me some of the trouble of unplugging the bat, pulling out the cluster, open it, list, close it, put back in, replug the bat, drive to Addison, buy, drive back, unplug the bat, pull out again...

[Blitzkrieg Bob]

Are you doing the blue cluster ? Could you list the caps if so ? That would save me some of the trouble of unplugging the bat, pulling out the cluster, open it, list, close it, put back in, replug the bat, drive to Addison, buy, drive back, unplug the bat, pull out again...


But I have a blue one at home, if you want to wait till I get home and look at it. But I'd hate to set you up for trouble, I think there may have been several makes over the years with a different set of caps.

[BMWDriver]

But I have a blue one at home, if you want to wait till I get home and look at it. But I'd hate to set you up for trouble, I think there may have been several makes over the years with a different set of caps.

Well, take a pic if you can, I'll compare it to the picture I took of the whole board. No rush, I probably won't go before Thursday. The important thing is the µF and V ratings.:) Very very much appreciated.:)