Author Topic: Please help out the newbie! (Read 4604 times)

DipStick · « **on:** April 18, 2007, 10:17:02 PM »

A first post would probably better be put to use as an introduction, but I guess I'll just have to use post #2 for that... I have some questions about my newly aquired '91 318is that I cant find answers to:

1. This is going to sound silly, but where / which / what light is the SRS (airbag) light? Wherever it is, it does not light up ever, even though the harness for the squib has been CUT OUT of the steering column. (I found this out when I pulled my cluster out, yes it made me mad). I have found the wiring diagram posted elsewhere here, but it sure would be nice to know where this light is supposed to be, so I can troubleshoot a little more effectively:eek:

2. As I understand, the service indicator should display even with the engine running, right? Mine only displays with the key in the "on" position BEFORE I start the engine. I was able to perform the reset (which did appear to give me all my green segments back) but it still does not display at all with the engine started.

2a. I pulled out the service indicator board and it appeared to never had been modified, but it had lithium batteries installed on it?!? Did the late e30s come with lithium batteries on the SI board?!? At any rate, both cells measured a strong 3 volts. I think that this may be some kind of remanufactured board, but had no such markings on it, just your typical BMW stickers. Any thoughts?

3. While not that important in and of itself, I see that there is a chime module, though I have never heard a sound. I have only found a partial diagram for the chime module in the e30_91 PDF on this site, but I cant find out what else feeds into this box.

So does anyone have any diagrams to help fill in some of the blanks here, or can anyone provide any pointers as to what I should check into? I work on aircraft avionics systems for a living, and know how to troubleshoot, but it sure does make all the difference in the world when you are armed with the right info to start with! I really do appriciate any help you can offer!

Thanks for reading!

Paul

gearheadE30 · « **Reply #1 on:** April 19, 2007, 06:46:08 AM »

Welcome to the club!

1. the SRS light is on the panel in front of the sunroof crank if you have one. It looks like it is just a black plate unless the light is on. If there is a problem, the light will flash for about five minutes after starting the car and will stay on constantly after that.

2. It is normal for it to shut off while the engine is running, mine does it too. Not sure why BMW didn't make it stay on the whole time though.

2a. Lithiums weren't around in the early 90's. The standard batteries should be NiCD's in a AA size IIRC. It is fairly common for people to replace the stock batteries with lithiums or newer AA's when the originals die.

3. Sorry, can't help you here. Anyone?

Sorry, I don't have any diagrams, but the Bently Service manual is an invaluable tool for working on these cars. It can be found at Amazon.com. Unfortunately, the M42 engine is in the E36 book, but all the electronics should be in the E30 one. A Chilton's guide for the '89-'98 3 series came with my car, it also has some diagrams. Good luck and enjoy your stay

DipStick · « **Reply #2 on:** April 19, 2007, 12:50:47 PM »

I pulled the panel and found it disconnected, go figure. Thanks, I had no idea there were lights in there! Thanks to Gearheade30 for the info!

Question 1: Once I have all the faults in the SRS system corrected (like having the airbag actually hooked up!), will the SRS light quit flashing on its own, or is there some kind of reset that needs to be performed?

I do have both the E30 and E36 Bently Service manuals, but it would seem that they are just not as complete as they should be. Good examples are the SRS missing in its entirety, and little things, like the chime module, which are only half covered, and incorrect for my particular car; There must have been some changes in the later years.

Question 2: Can someone tell me what all conditions cause the chime module to sound? It appears from this crappy diagram that it is at least the following conditions:
*Key inserted, with door open
*Seatbelt unbuckled (first 5 seconds)
*Signal from OBC (possibly for temperature, low fuel, ?!?)
**One other thing that I can identify because there is a mystery wire feeding into the module that isn't in any diagram! What is it?

Question 3: I forgot to ask originally, but where is the outside temp sensor located? I am tired of it being -22 outside!

If anyone can provide any answers, it would be greatly appriciated!

ak96ss · « **Reply #3 on:** April 19, 2007, 01:18:42 PM »

In theory, the SRS light should stay on until the code is cleared. The unfortunate reality, however, is that the dealerships don't have that equipment anymore and there is no aftermarket solution that I am aware of that will reset the light. Problem seems to be the pond-water baud rate - it is too slow for anything to talk to it. At least, that's how I understand it. I fiddled with the check panel and disabled the light entirely - true, I don't see alarms anymore, but I don't have an airbag anymore anyway.

Outside temp sensor is in the duct leading to the driver's side front brake, yellow connector.

gearheadE30 · « **Reply #4 on:** April 19, 2007, 03:29:28 PM »

The only other cause of chiming that I have had is leaving the headlights on. Otherwise, that list covers it.

Wow, I guess I'm not the only one with the -22 problem. Unfortunately, when I looked under the car I realized that my brake duct is missing. Looks like I have another project

As far as SRS reset goes, there is a diagram here that shows where the pins are. Unfortunately, I have seen only one tool to reset it, and it was $250.

DipStick · « **Reply #5 on:** April 19, 2007, 04:26:21 PM »

LOL, yeah my brake ducts are gone too! I just hope I can find the connector. I found a semi-local place called "Strictly BMW" that says they can reset it / check for codes for like $50. I guess when I get this mess back together I will have to pony up.

I bet my mystery wire is for the lights then...I will have to check it out tomorrow, I gotta get ready for work now.

Thanks guys, you rock! I will follow up here when I get it all sorted out.

Paul

kona2four · « **Reply #6 on:** April 19, 2007, 07:41:37 PM »

http://ee1394.com/bmw/docs/e30_91.pdf

kona2four · « **Reply #7 on:** April 19, 2007, 09:41:15 PM »

christophbmw · « **Reply #8 on:** April 21, 2007, 12:59:05 PM »

Quote from: gearheadE30;24053

Welcome to the club!

1. the SRS light is on the panel in front of the sunroof crank if you have one. It looks like it is just a black plate unless the light is on. If there is a problem, the light will flash for about five minutes after starting the car and will stay on constantly after that.

hmmm, when i bought the my 318is 4 years ago my SRS light did the same thing, i thought that when it flashes there is a fault in the system, so i took the light out because it was anoying (removeing the light probabally dis-engages the srs system). Anyways if what your saying is true then i will put the light back in.

does it do this for anybody else?

Febi Guibo · « **Reply #9 on:** April 21, 2007, 02:08:35 PM »

The majority of our SI boards have sanyo 3.3v lithium batteries... although your board may have new ones soldered in. If the batteries don't have a glob of hot melt glue on them, means they were prolly replaced at some point.

and... WELCOME!

fyi, the bentley manuals (even the e36) are of limited use; check our forum's REFERENCE section for tons of factory specs and diagrams, including the electrical troubleshooting guide.