electrical problem with cluster help!!!!

[usmcrob6]

i have been working on bmw 325es its and 86. ok here is the problem. when you start the car all the gauges work for about 4 secs then they shut off the tach, stat,gas and mpg just all drop but the speedo still works and the anti lock light still comes on. we have changed the ignition switch and moved around some of the relays its one of my customers cars and i am pretty new to bmws so any help anyone

 

[E30m42cab]

If you're sure this wasn't happening before you got the car, it's most likely your SI Board batteries.
http://www.pelicanparts.com/BMW/tec...placing_service_indicator_board_batteries.htm
Actually, if the car has had the battery unplugged, you might just need to run the car a bit to get the SI batteries up and working again... but more than likely, they'll need replacing.

 

[Big Daddy]

Scott is correct, an 86 most likely the batteries have given up.

 

[Doughnut]

Scott is correct, an 86 most likely the batteries have given up.

I'll +1 the batteries with scotty and huge dad.

 

[usmcrob6]

but if thats it then why do the gauges and stuff work when you start the car but then they turn off? the ac and heater dont work either but it works when you start the car but when the gauges stop working so does the heater and ac.

 

[Doughnut]

Purhaps a relay getting to much power?

 

[AWD_Guy]

I just give the old bird a punch and everything turns on. :lol: