Speedo etc

[nomininolife]

I have just purchased my first BMW, it is an 89' 318i touring. It runs perfectly fine but I did not notice when I test drove it that the speedo did not work. I have had a read through the posts on this forum and it appears it is a common problem. I have to check the connector on the diff and the connecting wires, now if this does not cure the problem it appears I will have to replace the instrument pod. Will a pod from any E30 fit or is it engine specific?

Thanks for your help

Dave

[eko]

Welcome to the Zone mate!

You will need to replace the speedo with another from a 4 cyl car.

Try the diff connectors first as this sorted mine out,failing that you will be able to pick a replacement up on here easilly.

HTH

[Widge]

Before you replace the pod, try taking it out and tightening the bolts on the back. Redoing the diff connectors worked on mine, but I have been told these bolts connect the circuitboard on the back of the speedo with the mechanisms inside, so when they come loose it leads to intermittent working of any of the instruments.

Idaelly if you have to replace it you need the correct instrument pannel, however if you can get one of the same design for a different engine you can swap the coding plugs (depending which design it is).

[Brianmoooore]

Before you replace the pod, try taking it out and tightening the bolts on the back. Redoing the diff connectors worked on mine, but I have been told these bolts connect the circuitboard on the back of the speedo with the mechanisms inside, so when they come loose it leads to intermittent working of any of the instruments.

Idealy if you have to replace it you need the correct instrument pannel, however if you can get one of the same design for a different engine you can swap the coding plugs (depending which design it is).

Nuts on the back of the cluster affect the fuel gauge and the temp gauge only.
Any later type cluster can be used as long as you retain your car's coding plug on the front, or you can just swap a speedo into your existing cluster, but the problem is most likely to be with the wiring to the plug on the back of the diff.
Sretch the idividual wires one at a time.

[bigdek]

check fuses also.

mine didnt work as a dodgy radio install from the previous owner continually blew the fuse which is shared with the speedo

[Brianmoooore]

check fuses also.

mine didnt work as a dodgy radio install from the previous owner continually blew the fuse which is shared with the speedo

Yes, don't forget the very basics of course! Fuses 10, 12, and 21 are all associated with the instrument cluster.

[nomininolife]

Today I have eliminated the fuses as the cause. Fuse 12 was blown, which I replaced but no change. The search continues.

[nomininolife]

It appears I have not eliminated the fuses as the cure. Fuse 21 blows as soon as power is introduced to it. Is there a common fault linked to this fuse or is it a matter tracing through to find the fault?

Again thanks for the help

Dave

[Brianmoooore]

I. Is there a common fault linked to this fuse

Yes, two.
Glove box light on early models, and boot light wiring on the boot hinge.
Unfortunately, neither of thes applies to a 89 touring. (Unless your glovebox light works without ignition on).
Radio memory feed is also on this feed, and having seen some very dubious radio installs in my time, then this is where I would start.

[nomininolife]

Sorry I got the wrong fuse, its actually fuse 12 a 7.5 amp fuse that is blowing. Any help is greatly appreciated

[Brianmoooore]

Sorry I got the wrong fuse, its actually fuse 12 a 7.5 amp fuse that is blowing. Any help is greatly appreciated

12 is also a radio feed, so same answer.