dash brake pad light goes on intermittently,also coolant light on my check panel

Hello to all my buddies who love their Bimmer's as I do. I have owned my 88supereta since 1991. The car has cost me a small fortune in repairs over the years but I can't part with it. I'm hoping that someone here can help me with latest problem(s)-lol Yes like most here I have been learning to fix small problems myself finally. In March 2010 my brake lining warning light was on steady. I had new pads.rotors and sensors put on however intermittently my brake lining warning would go on. I had the car checked many times and keep being told the brake pad,rotor and sensors are working.Has anyone here dealt with this problem?? I believe my second problem I may have solved but before I buy the part I thought I would seek advice. Problem-ON my CHECK PANEL my coolant warning light goes on intermittently too. My coolant is full however the warning light continues to go on from time to time. My thinking is that I need to replace the coolant level sensor. Did I figure it out-lol- I figure if I did I got one out of two. I really am glad to be a member here. Look foward to hearing other members expertise. Thx

Yep, coolant level sensor in the coolant tank cap could be going south. As for the brake pad light, did you change the wear sensors when the brakes were done? Most likely, you have a bad brake pad wear wire-sensor, again, relatively easy and cheap fix.

alan

Hi Alan, Thx for the info. Now on the brake pad sensors, I had them done at Firestone which is probably why I am having problems. The mechanics at Firestone tell me that have tested the sensors 2 times and they are good. Is there anything else besides bad brake sensors that could cause the brake pad warning to come on sometimes? The brake job is still under warranty so if you think thin it could be is bad sensors I take it back to them. Dave here also in SO. California

The sensor system works when the pad wears to the point that the disc hits the sensor severing the wire embedded in the sensor. At that point, the warning light goes on. You could have a broken wire down stream of the sensor or possibly a bad connector where the sensor plugs into the body wire loom. I think there has even been a mention of the sensor wire not being routed properly and then gets mowed in half once again activating the warning light.

Typically, when you replace the pads, it is good practice to install new sensors. There is one on the driver's front and the passenger rear (2 wheels, not on all 4 if memory serves me).

HTH

alan

Alan I really appreciate this. I did have new sensors installed when the brakes pads, and rotors were installed. I am going to print out what you wrote-I will not include your name. Then I am going back to Firestone since the pads, rotors and sensors are under warranty still. Thank you!!!!!

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my88supereta
Alan I really appreciate this. I did have new sensors installed when the brakes pads, and rotors were installed. I am going to print out what you wrote-I will not include your name. Then I am going back to Firestone since the pads, rotors and sensors are under warranty still. Thank you!!!!!

Hey Dave, On my 88 325is I did away with the pad sensors (and the bulb on the dash) and check the pads every so often physically. One option.... Welcome to the club

Rick

Dave, you can download a free pdf file containing full wiring diagrams for your car from either of these two sources:
http://shark.armchair.mb.ca/~dave/BMW/e30/
http://wedophones.com/BMWManualsLead.htm

Find the page that describes the Brake Warning System (section 3435). There you can see that it's one continuous circuit looping through the sensor in the right-rear and left-front. If that circuit is opened anywhere, i.e. the wire is broken such as happens when the brake sensor is worn through, or the wire is grounded out anywhere, such as happens when the worn through end of the wire in the sensor touches the brake rotor, that will trigger the brake lining warning light.

More often than not though, it'll simply be a cracked wire somewhere, or a bad connection in one of the many connectors or splices in the circuit.

The warning light kept coming on intermittently in my car too. It bugged me. I wasted hours trying to track it down. I finally gave up and simply removed the bulb from the warning light in the instrument cluster. I have the wheels on and off my car often enough and always check the condition of the brakes. I can live without that warning light. But good luck to you, it may just be a loose connector.

The coolant level warning light actually is useful though, and that one is worth fixing. You can find the wiring diagram for that in the pdf document in the section for the Active Check Control (section 6216-2). The coolant level sensor, same as the washer fluid level sensor, is a float switch that is normally closed when the level is okay. If the fluid level drops too low the switch opens, thereby triggering the warning light in the overhead check panel.

You can cheat by unplugging the sensor and sticking a paper clip into the connector to permanently complete the circuit. But I would strongly recommend you don't do that, because it is useful to have the warning light functional in the event of a coolant leak. The float sensors do sometimes fail when the float ceases to float. They're relatively cheap to replace. Try Bavarian Autosport. They have everything and are very easy to deal with.

One of my cars has the same problem. The light is on most of the time. Occasionally on the freeway, it goes out for a while. I should probably just take the bulb out too.
Bob in Everett

Hello Everyone, I purchased a new coolant level sensor and removed the old one. Then I reconnected the new one and started my car. What a surprise, The coolant light is still shining bright!!lol- I bought my car in Boston way back in 1990 with 26,000 miles for $15,500. Apparently the previous owner had traded it in for at the time considered a hot commodity a Mazda Miata. I have always been curious if he traded the car because it was a lemon or if he was just caught up in the Miata hype at the time. Now I feel old because so many owners of e30's were children when the Miata was the first new sports car two seater with all of fun of the triumph spitfires and the updated Japanese Technology to spare owners spending their life savings the repair bills British triumphs were known for. Twenty years later think I either got a lemon or perhaps e30's have a long engine life only if you spend and spend and spend. Does $20,000 in repairs over 20 years sound like I got a lemon? I have replaced 3 air conditioners-the last one was a nightmare!!! I also have a 330cic mystic blue convertible which looks incredible. My plan was get as much cash out of my 88 and enjoy at what I had read in consumer reports a much better built vehicle. Oh yea my 88 now has 126,000 on it. That 5k a year over 20 years. It was stored from November until April for the first 12 years. I wanted to share this with other E30 owners to see if any are owners long term like myself. If there are some think a got a great big lemon?? Anyways I love the car and my 04' is sitting in my garage 1st due to the fact I have almost smashed into other cars to the right of me on expressways because there is a major blindspot in that model. It's impossible to detect cars to the right of you when they are in that blindspot. My 04 is a total different animal. I went from a sports coupe to a head turning car that drives like a Mercury Marquise!! Beware-lol- I just ordered a set of European convex side mirrors that are supposed to eliminate the blindspot I can't wait to see if they work. I guess I will be taking my 88' to the repair shop for the coolant level light and the brake pad light which goes on and off. UGG here everytime I get stuck for at least $1000. My 04 has 26K I bought it in 05 in St.Louis!!! Flew there on a whim and picked it up for $32,500 instead of $46K they were selling for in San Diego. That car I purchased with 19K and drove it from St. Louis to San Diego at about 1000 miles-so 6k I have driven it from 05-2010. NOT Cheaper-has to replace 4 tires because the are low profile. That was $1000 for the rear and $500 for the Front. The dealer has recommended replacing the front bushing when and if my car reaches 30k the mileage for the 1st inspection. I think they are the most beautiful automobiles on the road. But man they are not built well. No way!!! Okay COMMENTS!!! ANYONE-Does everyone hate me or are you all rich?? LOL-

Did you try shorting out the connector with a paper clip like Ferdinand suggested? If the light still stays on, your problem is downstream of the connector at the coolant tank. If the light goes out, is the coolant tank all the way up to the full mark? Also, test the float itself, it wouldn't be the first time a new part was bad.

alan

Hi Alan. I know you mentioned how to check the new coolant sensor but I'm not clear on the exact procedure and I'm somewhat nervous I may do more damage. Here's what I know so far. I start the car remove the new sensor keeping it attached to the car wiring. Then didn't you mention to use one of those testing devices to see if the sensor is getting electricity? I have the device with it looks like a screw driver , a long metal poker that goes into a plastic clear handle. Inside the handle is a small light bulb and there is a separate wire with a clip. I am supposed to touch the prong to something and clip the single wire to something and see if the sensor completes the circut and the light inside the handle goes on? Alan you are really a generous person sharing your expertise. I have been up since 3am and that tool is in my car so I can't even tell you the name of it. Did you tell me about the tool and testing the new coolant sensor or did I read that somewhere else? I have researched so many places thats why I am tempted to get ripped off and leave the car at a garage.

Alan the sensor I bought screws into the small plastic coolant tank. The tank is filled to the brim. What do you mean test the float? Is the float inside of the plastic coolant tank?

The float and cap are integral (same) part. Just pull off the connector that attaches to the cap and short it with a paper clip. You won't do any damage to the electrical system nor will you receive a shock. If the light goes out, the issue is a bad sensor even if it is new.

alan

Hi Alan. First off after all my bitching about the expense of owning a BMW I do want to say that after 20 years of driving me 88, I still love it!!! I will try your suggestion on testing the coolant sensor. I'm not sure if I mentioned this but I started buying parts from Bavarian Auto Parts when I lived in Boston and still buy from them and seek their advice. One of their representatives said that there is a master board that uses batteries. He indicated often when the batteries start to leak that can cause warning lights to come on for no reason. If I find that my new coolant sensor works would the next step be to examine the master board batteries that the BA Rep. mentioned? I will update you after I test the coolant sensor. I have one other question for everyone. I live in San Diego and there is a repair restoration BMW company located in La Jolla just north of me. Most of their restorations are on the bmw2002 and the six series from the 80's. On their site they discuss the e30 model and they recommend the 325is model for anyone looking for a great car at much more reasonable price than 2002's series. I have never had the chance do drive the 325i or the 325is. I know that engine has a smaller displacement and more horsepower 189 versus 127 on mine. I did add a performance chip from Dinan so my horsepower probably is up from 127. Is the 325I and 325is substantially faster and better than my 325? I ask because I see them relatively cheap and I wonder if I should sell mine and buy the i or is model. The company in La jolla believes that model will be the next 2002 as far as becoming a classic and in the next few years should appreciate in value. If I'm putting money into my plain 325 perhaps I should get the i series and down the road get a payback on investment. Thx everyone

ALAN RW THANK YOU!!! I ..I took a paper clip and inserted it into the sensor wiring plug and the coolant warning light went off. Apparently the new sensor I purchased is faulty. Now I just need to return it and hopefully get one that works. Thank you Alan and to everyone here that helped me out.

I was right? Really?



alan

YES YOU WERE!!!!

You shouldn't be surprised; you've been around here long enough to know most of the things that can go wrong.
And how many times have we seen new parts that were defective...too many

Congrats on getting your brake warning light sorted!! Hope it has restored your faith in E30s and improved your confidence to get your hands dirty. Start off with diagnosing and replacing a brake wear sensor, next thing you know you'll be blueprinting engines!

Just a suggestion, long posts without paragraphs are hard to read. You will get more responses if you break them up into paragraphs.

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my88supereta
...there is a master board that uses batteries. He indicated often when the batteries start to leak that can cause warning lights to come on for no reason. If I find that my new coolant sensor works would the next step be to examine the master board batteries that the BA Rep. mentioned?

Yes. They are called the Service Indicator batteries and all kinds of crazy things happen to the dash when they stop working.

You should buy the Bentley E30 service manual (here's the link: [www.amazon.com] ). The first time you use it, it will pay for itself in the money you saved by not going to the mechanic!

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my88supereta
Is the 325I and 325is substantially faster and better than my 325? I ask because I see them relatively cheap and I wonder if I should sell mine and buy the i or is model. The company in La jolla believes that model will be the next 2002 as far as becoming a classic and in the next few years should appreciate in value. If I'm putting money into my plain 325 perhaps I should get the i series and down the road get a payback on investment. Thx everyone

Here's the specs: [e30world.com]
The 325i is quicker than the supereta only above about 3500rpm, if you don't want to rev it out then the supereta will be quicker. (I haven't driven a supereta though)

As for the investment side of things, (with a few rare exceptions) there will never be any payback on investment. You buy it to enjoy it, not to make money- cars are terrible investments!! The 2002 may be considered a classic, but even then you won't find many people who have actually made money off owning one (especially when you consider the costs in keeping it in pristine condition). And buying another car gives you a heap more unknowns, the 325i you buy could need more work than the supereta you've got. If you want the added niceties of a 325i, I'd say you're better off adding 325i bits to your 325 (most can be just bolted in without modification) than starting from scratch with an unknown 325i.

If you want more power, your 2.7L engine is a great starting point for modifications. Many people use the eta block with the 325i head to make good power (and since your supereta already has some 325i parts, I'm guessing there'd be less to swap).

Cheers,
Simon

PS The E30 is not a lemon!! Any 22 year old car is going to need things replacing to keep it working well. This forum (and many others) is proof that it's worth the effort.

The payback is that this is the best car I have ever owned. All of my friends who have driven the car say it is a very fun and surprising car to drive.

Hail the E30!!!!

alan