Having problems

My 1989 735iL is having problems. All gauges don't work. Car starts and runs well. What causes this?

Fuse #1, #17, #20 are all related to the cluster I believe. I know #1 is for sure. If you have checked these and they look good, try taking them out and reinserting them. If that doesn't work, replace them with the EXACT SAME amperage fuse. Sometimes, just because a fuse looks good, doesn't mean it is good. Tiny fractures in the fuse bit might be separated enough to not allow good enough contact, and thus looks ok but isn't.

Out of curiosity, are your brake lights working as per normal? If something isn't right with your brake lights and fuse #1 blows, your cluster will go dead.

It also might be a loose connection behind the cluster. Although I do find that pretty unlikely. In any case, if it is a loose connector, you might want to spray some electrical contact cleaner on the contacts first and LET DRY COMPLETELY BEFORE REINSTALLING.

There's also a capacitor fix that you can do that are sometimes the cause of a lot of problems related to the cluster...let us know how the fuses go first and I'll try to find the write up on how to replace the caps.

Okay guys, I tried replacing the fuses that affect the instrument cluster and gauges #1, #17, & #20 but the same result. My obc had defaulted to pppp but now is miraculoulsy working. What should I do next? Everything else works fine...

It may be possible that pulling the fuses may have "reset" the cluster...you say it defaulted to PPPP (indicates to me that it's a sort of "boot" program after reset, like turning your computer on in the morning). Although I would have no idea as I'm not too familiar with the behavior of our clusters (aside from speedo readings, etc).

If it works fine, LEAVE IT BE! :grinyes: It's quite possible that you fixed it and, as you say, is now working fine...

Okay guys; here's what happened: after the miraculous working of the obc, which reset itself. All gauges started to work. I had noticed that while driving earlier the "brake fluid light" would come on and go off intermittently. Then, as all the gauges began to work again the light went out. But immediately while driving and stepping on the brakes for the first time after everything worked the gauges went dead again. Tell me if it has something to do with the brakes or as you stated earlier the "brake lights" or is there a loose connection by the brake pedal or is it in the electrical connection at the tail lights?

Thanks again...

First off, check your brake fluid to make sure it's filled properly. If it is, don't worry about it. If you get that same warning again after you've fixed the cluster, you might be looking at a loose brake fluid sensor connector or a knackered sensor.

Check the tail lights at the rear to make sure all are working properly. If they are, move onto the brake switch.

If your brake lights are working fine and you've wriggled the connectors in behind the trunk, you might be looking at an LKM fix (Light Control Module) although I'm not sure if the LKM is even remotely related to the cluster.

Check the fuses again and see which one(s) have blown, if any. If one did blow, then you are most likely dealing with a short circuit on one of the systems that fuse is fusing. If all looks ok, replace with another one just for good measure.

If all checks out well, I'd suggest you pull the cluster out and reseat any connectors on the cluster (take off and put back on). If that doesn't fix it, I'll put you in contact with someone who'll be able to help you more indepth...

Okay guys, here is the latest... While driving last night, the unthinkable happened. All gauges went dead again and the headlights went out. I had to drive with the fog light to get home. This is getting irritating. Is there any feasible solution to this electric mayhem? Please help...

Thanks for all the previous responses.

Wow, that's no good! I'm glad your fog lights still worked.

At this point, I think I mentioned a few posts back about the LKM. Unless it was just coincidence that your both of your headlights went out, this might be causing your problems, however, like I said, I don't know how much of the cluster the LKM will affect, aside from illumination, maybe.

LKM and Mustard Relay fix (http://www.e32fixes.com/results.asp?method=show_fix&fixid=1)

http://www.bmwe34.net/e34main/maintenance/electrical/LKM.htm

Thanks, lincolnmaster80... I'll give it a shot and see what happens. Can't hurt to try....

Lincolnmaster80 has made some excellent recommendations. For information, you can pick up a rebuilt LKM on eBay and many also have a warranty. It may be a good idea to pull all of the modules and reseat them, as corrosion can build up on the contacts and result in electrical gremlins. I have a 1994 740iL, and I also had to replace the brake light switch as they had a recall for a defect that caused false brake light failures. I can't remember if this fault went back to 1989.. Keep us posted.

Hey, thanks lincolnmaster80, resoldering the LKM and Mustard Relay did fix the lights problem. But I still have the cluster (gauges) problem. Remember, last week I stated that all the gauges miraculously began to work and then immediately stopped when I applied the brakes. Well, the "brake fluid light" comes on intermittently and stays on from time-to-time. I checked the brake fluid reservior and its full and the electric connection has no corrosion. In addition, I did what muleman suggested and pulled all of the modules and reseated them but to no avail. Should I now pull the cluster to check for a loose connection? I can think of nothing else left to do. Please advise...

Glad to see you got your sight (lights) back! :grinyes:

I would try and reseat the cluster connections. Glad to know for sure that the LKM dosen't affect the cluster.

NOTE: IF YOU HAVE AN AIR BAG, IT IS CRITICAL YOU FOLLOW THESE INSTRUCTIONS ON THE WEB SITE BELOW. (You'll find out why in VERY short order if you don't)

Some changes to note:
1. Battery is under the rear seat on the right hand side. To disconnect the battery, there's a black plastic access cover just under the seat. I believe this is the negative battery cable. For instructions, see my "Magic Reset (http://www.automotiveforums.com/vbulletin/showthread.php?t=684216)" post. (If you wanted to try the magic reset first, it's helped "cure" some other problems unrelated to the cluster)
2. Air bag connector might not be orange (not sure what color it is if it's different)
3. You might be able to remove the cluster or fit your hand behind there without removing the steering wheel. Some have been able to do it on similar styled E34 5-series.

Instructions for steering wheel WITH air bag (http://www.bimmernut.com/~billr/images/airBagAndBulbs_files/airBagAndBulbs.html)

Instructions for steering wheel WITHOUT air bag (http://bmwe32.masscom.net/sean750/dash_bulbs/changingClusterBulbs.htm)

As I was doing some research, I didn't really find any specific to your problem, but there have been a lot of "weird" problems with the earlier E32 clusters that were solved with a Capacitor fix. If reseating doesn't help, then I'll refer you to some "higher ups" (people who are more experience with solving cluster problems than I am) before I recommend the Cap Fix.

http://bmwe32.masscom.net <-- BOOKMARK THIS SITE

Hey lincolnmaster80, thanks for all your guidance...I pulled the cluster and ran the volt meter across the capacitors and just like you said it was the capacitor. So I replaced the bad one and now the cluster works like a charm. I really appreciate all your help. I look forward to coming to you again for help. Thanks again.

Good show mate. I'm happy for ya! Glad to see another E32 in a happy working state of being!

Okay guys, I'm back with another one. My 89 735il has been running just fine as of yersterday. However this afternoon, I tried to start it and the fuel pump message was displayed. I checked the fuses and they are okay. The tank is full. Could it be the fuel pump or something else? Need help again...

Before you start, you should wait in key position 2 for a few seconds, just so the fuel system and electrical system can charge, then turn it over.

There should be a slight buzzing/humming noise when you leave the system to charge for about 3 seconds before starting. If this buzz/hum is not there, you're looking at either fuel pump relay or the fuel pump itself.

Check the relay first because it's easier to check. Try the good old fashioned "reseat" method. It is in the "E-box", the box on the other side of the engine bay and looks exactly like the fuse box on the drivers (left hand) side.

Fuel pump relay is the only orange one in that box:
http://bmwe32.masscom.net/johan/e_box/ebox_1987_735i.jpg

If this doesn't change, the fuel pump replacement is found at Johan and Sean's E32 Page. The write up is for a 750 but I think the procedure is pretty much the same. Where ever there are two send lines, there will only be one for your car. If I remember correctly, he even touches on how to test them, if you feel like your up to it...

Fuel Pump Replacement (http://bmwe32.masscom.net/sean750/fuelpump_replacement/Fuelpump.htm)

If there is a humming and the system is charging, make sure that your gear stick is in P. It might also be your starter relay, which can be found here:

http://bmwe32.masscom.net/johan/e_box/fuse_box.html

Let us know how it goes.

Hey thanks again lincolnmaster80...I'll give it a try.

:banghead: Okay guys, I'm back looking for help. My 89 735iL message center shows "trans program". Now it doesn't go into gear. I've tried every gear but nothing. After sitting for about 2 hours it did go into reverse but hesitated when placed in drive. Is this a computer glitch or is this a more serious problem. The tranny has around 199 thousand miles on it. Should I start looking for another tranny?

Sincerely,
Cajunboyla

Before I explain in detail, here's a list of things to check:

1. Battery voltage (at the battery itself under the rear seat)
2. Tire pressure
3. The transmission program button next to the shifter stalk is clean and the contacts for the shifter stalk are clean and corrosion free.
4. Transmission wiring harness


Now then, those are the main things to check. Here comes the details.

1. Proper Battery Voltage: These cars are pretty sensitive to battery voltage. Anything less that about 10 volts, the car will do wierd things. Make sure the battery is good and has a stong voltage of about 12V, +/- .5 volts. Try the "magic reset" (found on the main 7-series forum), this method has been known to solve some problems. If the problems come back after the reset, it is because your computers have relearned the problem the car is suffering.

2. Correct Tire Pressure: If one tire is not properly inflated, the brake/ASC sensors will detect the lower pressure tire as spinning to fast because it has a smaller diameter and the car will shift improperly. However, you'd notice this symptom only when the car is in motion, as you've said the car doesn't go into gear at all to get moving. But it's still good to check these things!:grinyes:

3. Shifter Stalk/S-E-M selector: After 199,000km's, these two circuits have seen a lot of use. The one you're probably most concerned with, however, is the shifter stalk contacts. You can take this out by following the instructions on the web site below. Clean off with electrical contact cleaner and let dry COMPLETELY before reinstalling. Quick question: Is the gear displaying on your dash?

http://www.nmia.com/~dgnrg/page_13.htm


4. Transmission Wiring Harness: Located underneath the car, this sometimes can wriggle itself loose and become dirty. You'll have to jack the car up and crawl underneath. Of Course, if it is dirty, it's a good idea to clean it off now while you're there. Disconnect the battery before you clean off and, again, let dry completely before re-inserting. I'm not sure where this connector is...I'll look for some pictures or write ups to help you out...


As always, let us know what you find. These are just the basics to check first.