Bmw635

Doing cluster refresh so I tried to fix the no alternator light but bulb is working, resistor is 72 ohm. Flex circuit is good and clean with silver pad, not copper. What would cause no alternator light?

Also have no D shift light on cluster. How do you get to the bulb? Seems like it's been done before with a wire- see pic. Thx.

Btw, the cluster is made by VDO so all the bulbs and sockets are the same as BMW so most BMW parts store should have these bulbs for $.80 each.

Alan

If the alternator connection is missing the light stays off...

Test it - with the car not running but ignition on - find CE plug connection M13* or K23** (or the 14 pin engine loom connector - pin 1 - blue wire) and short this to ground - the (no) charge light should come on. (BTW these are for an '88 - it varies by year)

If it illuminates - you either have a connectivity issue between these points and the alternator's D+ (61) terminal - or the alternator regulator has a problem.

Alan


* CE panel Plug M 3rd pin up on left hand side
** CE panel Plug K 3rd pin up on right hand side

Bmw635

Hi Alan,

I am trying to replace the D bulb in the cluster but only found LED locally, no incandescent with bi-pin or lead to solder on. Do you know how to tell which trace on the PCB is +/- for the LED placement? Any idea on what other bulb I can use?

I am trying to fix this cluster to reinstall before checking the wires/ connector you mentioned. I assume bulb is OK, resistor is 72ohm so I can button up the cluster for the no alternator light ? Thanks.

Alan

The 1.2W cluster warning lights are bi-pin incandescent capsules soldered to a plastic base - you can just take one apart and solder it in... easiest & cheapest route and you probably already have one?

Alan

Bmw635

Good news, bad news. I got the D light soldered in, clean the cluster reflector and add the Monokote on the 3 prism reflector for more light output into custer with non-LED and it looks great. Here's a pic with no flash and pitch blk garage.

Bad news, good news : The oil pressure gauge light is on but gauge either peg max or drop to zero when I wiggle the harness and connector behind it. It was fine before the cluster refresh. The elusive no alternator light came back 2x while I was wiggling the connector and wire for the oil pressure but not again since. Is this sign of bad ribbon cable where the connector slide onto? Can't be the connector is it?

Ribbon cable looks newer with silver pads -no copper , and the blue laminate look blue- not aged.

WallyP

A good cleaning with DeoxIt, followed by a "contact enhancer" might help. Stabilant is pricey, but very, very good.

Bmw635

Did the Pope bless these 928 with Deoxit? Took out cluster again to bless it with Deoxit so everything is alive again. What a great satisfaction with this project. Now on to next one.Thanks all.