Instrument cluster issues E32

[dcs71]

I have an elec problem with my 1989 750iL, when i drive and turn the lights on the instrument cluster stops and the hazard light blink in the panel. if i turn off the lights the cluster does resume back to normal after a few seconds. This then throws up an error that the rear brake lights need checking, if i turn the car off and on the dash is all good again, until i turn the lights on. The Eccon - Park (trans indicator light) comes on but when I put it in to D the light goes out ? and the trip metre always goes back to 000.0 everytime i stop start the car, the main k's change and stay as they are though.

[dcs71]

My E32 1989 750iL has cluster issues, when i turn the lights on the cluster stops working, if i turn off the lights it will fix itself in a few seconds but it will display "brake light issue" on the display.

The display also shows the E P then when i put it in Drive the E P no longer displays, the trip metre works when driving but will always drop back to 000.0 when i stop and start the car, the k's still change and display as normal.

Not sure i should get the auto elec to look at it? was thinking might be an easy fix ?
Cheers David

750iL 1.JPG750iL 2.JPG

[shogun]

I will start, brake light: does it show bulb or brake light circuit? In case circuit, you might need a new brake light switch http://www.nmia.com/~dgnrg/page_25.htm
Disappearing light/gear mode: clean the switch and see what happens http://www.nmia.com/~dgnrg/page_13.htm

Not working tripmeter might be a dirty speed sensor or wire problem at the sensor http://www.bmwe34.net/E34main/Mainte...eed_sensor.htm
Or there is a cluster problem, the are on the electronic board where the push buttom for reset the day trip mileage might be oxidized. For that you have to remove the cluster and check, clean, resolder.
Or the caps must be replaced http://bmwe32.masscom.net/johan/dash...dash_caps.html

But with your problem with the light switch and cluster stops working an electric expert has to chime in.

Do you have a spare cluster to see if the problem goes away when swopping it?

I would also remove the light switch, maybe a blank wire contact or something wrong there.

[dcs71]

Thanks So much for all the help and guidance guys, i swapped out the cluster and all works well changed the coding plug over so the k's are still the same from the original, sooooo happy, my bronze beauty is back on the road

[shogun]

Glad that it worked so easy. Do not throw away the old cluster, maybe it can be repaired, new capacitors. As you changed also the coding plug, you should have a white backplate cluster
Application date.. Back plate colour.. Code plug type......... Size........................... Extra information
start ->02/89........... Grey............... HML 075......... 2048 bytes................. No self test or diagnosis via Modic. Stops at 299960. code plug is non-standard
02/89 -> 09/90 .......White............ PIC 93C46........ 1024 bytes................. Self test + diagnosis via Modic. Code plug is standard EPROM
09/90 -> end........... Blue.............. PIC 93C56........ 2048 bytes.................. Self test + diagnosis via Modic. Code plug is standard EPR

[dcs71]

Thanks yes i have kept the old one, but it looks like water has got to it as the big silver conductor on the plate has rust around the small vents of it, the Capacitors all look ok