Instrument cluster not functioning correctly!

I'm gearing up to do this...

No hurry as I have a another paired cluster/EKM in the car now.

I'm searching for the exact EKM I need (Not much luck).

I think I'm also going to get an EEprom socket, so once I get the little devil off, I don't have to reheat him and possibly ruin it.

email me if you want to talk turkey.

Replied in your other thread...

REVTOR; It will do no harm to look.
also by pointing out the BM thread I have made members aware of it's existance.

i did it my cluster was not working. bought a cluster from the junk yard it did not work look at the e31 electronic diagram you need the bod control module ekm in order for it to work. it is located under the foot rest on the driver side my car is left hand drive second module there are three located there.

The gauge cluster and EKM are married components and one is rather useless without the other. I have both in perfectly fine shape that I can send. You chaps there use the same display as we Yanks, no?

sandwich: Do you at any chance live near another 8 fellow who is willing to lend you their cluster - just a few minutes for testing is enough. Obviously the other cluster will detect mileage tampering and show "EEEE" on the odometer display, but the gauges should work properly. If they do, you know for sure the problem is in your cluster. If the other cluster's gauges don't work as well, it's quite safe to assume your cluster is ok. The EKM is then the next suspect.

Now, before you even think about this you need to be sure the other cluster will not continue to show the "EEEE" when it's back in the original car (otherwise you may have 2 "bad" clusters ;)). I've never done this, so I'm not sure what will happen. Perhaps others can chime in? If the cluster can be returned to the original car safely, this would be a good quick test for your cluster. Alternatively you can test your cluster in the other car (same issues may apply).

I hadde a similar problem and it was fuse nr 17 that I could not see that it was broken, try to measure all the fuses so that they are all ok.

As I understand it and having read somewhere, there is a sort of time limit before the test cluster is trashed, IE: that it has attempted to marry to the existing EKM but can't, and thus is rendered unusable without fault in the original car. I seem to remember 1-2 hours.

Zitat von revtor;78684

sandwich: Do you at any chance live near another 8 fellow who is willing to lend you their cluster - just a few minutes for testing is enough. Obviously the other cluster will detect mileage tampering and show "EEEE" on the odometer display, but the gauges should work properly. If they do, you know for sure the problem is in your cluster. If the other cluster's gauges don't work as well, it's quite safe to assume your cluster is ok. The EKM is then the next suspect.

Now, before you even think about this you need to be sure the other cluster will not continue to show the "EEEE" when it's back in the original car (otherwise you may have 2 "bad" clusters ;)). I've never done this, so I'm not sure what will happen. Perhaps others can chime in? If the cluster can be returned to the original car safely, this would be a good quick test for your cluster. Alternatively you can test your cluster in the other car (same issues may apply).

Zitat von sandwich;78695

All the tests so far seem to all point to the cluster. All signals are leaving the EKM as they should and seem to get no further than the cluster.

This I don't understand... You have a spare cluster that shows exactly the same (faulty) behavior. Then what makes you think it's in the cluster? My conclusion would be that it's very unlikely the cluster...

Zitat von rcrad6653;78704

As I understand it and having read somewhere, there is a sort of time limit before the test cluster is trashed, IE: that it has attempted to marry to the existing EKM but can't, and thus is rendered unusable without fault in the original car. I seem to remember 1-2 hours.

You refer to a maiden EKM or cluster. A new unused EKM or cluster can be changed between vehicles for up to 8 hours (counting when powered). After that, it's permanently paired to the cluster or EKM that's connected to it.

Now the Electrical Troubleshooting Manual Diagnostic Procedures (ETMDP) clearly states no coding data is exchanged when both are used an from a different vehicle. This seems to suggest you can safely test a used cluster from another car (for the gauges - not the odometer of course as it will show "EEEE") and later return it to the original car without issues. But considering the prices, confirmation from others who have done so may be at place ;). Anyway, this doesn't apply anymore - sandwich already has a spare cluster.

But on a sidenote... If someone ever gets a new EKM from the dealer, it would be great to hand it to someone to read the contents of the EEPROM before it was installed in the car. If we know what's in the EEPROM of a maiden EKM, it would be possible to change used EKMs into maiden ones which could really help a lot of people who are now facing the expense of a new unit.

Ok then. Steve, from our conversation I checked part numbers between the units I have and your '98.... it's the same part but there are about 5 different part number supersessions, including mine to yours. I have an extra EKM that is of no use to me, so send me your contact info and I'll fire it over the pond straight away. That will get you closer than you are now. If the cluster lights up you'll have to get another pair of course, but we'll cross that bridge later. This module is known good so if the cluster doesn't work we need to look elsewhere for the problem. If we're gonna throw darts they might as well be free ones......

I had a similar problem before you have to find a donor car and get both the cluster and the body control module. Or you will have to get the body control module coded to match the cluster.
Goodluck

Zitat von cura;78715

Or you will have to get the body control module coded to match the cluster.

And that's exactly what is impossible. In an attempt to minimize odometer fraud (or to raise extra cash for the dealers), BMW equipped both the EKM module and cluster with a countdown timer. Once either unit is past 8 operating hours, they can no longer be coded to another vehicle. So the only options are a brand new module from the dealer, or like you said a used EKM and cluster pair.

But at the moment I'm intrigued why sandwish assumes the problem is with his cluster, while his descriptions of the issue tell different...

Zitat von sandwich;78727

We have tested all pulses emitted from both the EKM and the general module with a scope....serivce guys words not mine! All information leaves the EKM, for example when the engine is running, the scope detects an increase in revs etc etc. These measurements have been taken at the instrument cluster end of the loom.

I have reread your original post and it seems the situation may be a bit more complex than I assumed. Basically the cluster gauges receive information from two sources: The fuel tank gauge, water temperature gauge and speedo get their data from the EKM while the tacho gets it data directly from the engine's DME module. The data link to the EKM is a single-wire digital bus. You cannot really diagnose it with an oscilloscope. The tacho signal from the DME on the other hand is a frequency-pulse signal. I assume that is what the service guys tested.

When I first read the topic I thought your tacho was the properly working gauge. Since the tacho is the only one which doesn't get its data from the EKM the cause seemed quite obvious to me. However, it's not the tacho but the speedo which kind of ruins my theory .

Unlock the MID service menu and lookop service menu 6 and 7 (current and average fuel tank contents). Do both give a proper and realistic reading? The displayed tank contents are retrieved from the EKM, so if the MID can display the correct fuel tank contents the cluster should as well. In other words, if the reading is ok the issue is probably not with the EKM.

There is of course still the fact the other cluster shows exactly the same behavior, which is... well... rather confusing. The way I understood it is that the gauges should work properly apart from the EEEE error in the trip/odometer display. But that may be incorrect information. Really nobody who can shed some light on this? I'd like to know as well.