Red and Yellow Brake Lights on

[Guest Keith_Milford]

Obviously, I'm not having a good day. Just picked up my beautiful 88 Reatta today, and, after driving about 150 miles, got a message about an anti-lock brake warning, low brake pressure, need service. Then I noticed the red brake light was on (the yellow one had already been staying on, but the brake system had been checked out, and the yellow light was supposedly not indicative of a brake problem; more likely an electrical problem). Anyway, I pulled over and checked the brake operation. The pedal was spongy, and when I pressed on it, it made a whine and slowly pressed almost to the floor. However, I was able to get it home, with one "hard pedal" incident. The "brake test" seems to be concerned with situations where the brake warning lights actually will turn off at some point; I don't have that situation. So, where do I start? I'm sure the info is here somewhere, but after sifting through posts for over an hour, I decided I apparently don't know how to search on this site.

Thanks for any help.

[Ronnie]

Take the brake test and report the results here. We can help.

[Guest Keith_Milford]

Again, each brake test seems to begin with some version of "wait for the lights to go out" or "count the seconds/pumps until the lights go out/on". My lights were alway on. I guess I'm not understanding something. Anyway, I just went out and cranked the car, and the red light did go out. Sooo, I will take the test and post the results as soon as possible. Then, hopefully, you fine folks can steer me in the right direction. I appreciate your quick response, and your offer of help in isolating this problem. I am extremely excited about the opportunity to have this car in the stable.

[Booreatta]

just a guess but I would start with 3 things. Pressure switch, accumulator, pump. Accumulator is suspect in what you post. Just a guess at this point. Jim Finn would have the pressure most likely and You can still order the accumulator from GM Parts direct

Good Luck

[DAVES89]

When you start to have brake light/brake issues very seldom do the lights go out while driving. The only exception I can think of is the brake sensors. They may help the light [amber] go back out. I have not heard of the red light going back out while driving.

At any rate, good that you are at home. Do not drive the car until you have both diagnosed and replaced the "bad" parts. With the "hard" brake pedal stopping is severly diminished.

Go to www.Reatta.net and take the brake test. Then report back with your results.

Do not be disheartened, most of us upon purchasing our cars have found some "gotchas" that were not disclosed by the previous owner.

If you keep the mindset that you are now a hobbyist with a rare car the initial money you spend will be easier to take. B&TM is right Jim Finn should have the pressure switch and the accumulater [iMHO] should be bought new.

At any rate welcome to the forum and post some pictures of your new ride.

BTW if you change your profile to include your city/state you might find a fellow enthusist in your area. Or at least advise you on a mechanic for some of the harder repairs you might run into.

[Barney Eaton]

Fairly simple test......

* Engine OFF, hood open

* Pump brake pedal until it gets hard.

* Turn ignition switch to RUN position, DO NOT start engine.

* Listen for the brake pump ....how long does it run before turning off? (less than 10 seconds is bad, more than 40 is bad, inbetween is acceptable)

* Pump brake pedal as if you were doing multiple stops (down/up, down/up) how many pumps do you get before the pump turns on? A low number (1, 2, 3)indicates a failing accumulator...somewhere around 4 or more is acceptable for now.

Once you have done the above and found the condition of the accumulator, you can move on to why the YELLOW and RED light are on all the time.

One condition that will cause both lights to be on is low brake fluid. If your fluid level is good, unplug the connector to the fluid level device on the side of the resevoir and see if the light go out. You could have a faulty or stuck sensor.

Sometime during this process, flush the brake fluid.

You probably have brake fluid that is several years old.

That pump does not like dirty fluid and the parts are expensive. Flushing the brake fluid is cheap insurance against Teves brake problems.

[Guest Keith_Milford]

I wasn't actually driving when the red light went out, just cranked the car in the driveway. but I guess your point still stands. I would like to think is was just a momentary electrical glitch, except that the behavior of the brake pedal would indicate otherwise. Also, the previous owner was very meticulous and forthcoming about the car, and there is documentation indicating the brake system was checked out recently by a qualified mechanic, and everything was fine. Just wanted to clear that up so as to show no ill will toward the seller. As an attorney, and an owner of many cars over 10 yo (currently eight, from 10 to 44 yo), I understand the concept of "caveat emptor", and that old machines break, usually at the most inopportune time.

In any case, clearly no one is going to be able to help me until I do my diagnostic homework. I'll get back to you as soon as I do the brake test.

Thanks again for the suggestions and encouragement. It would take much more than this to disillusion me on this car.

[Guest Keith_Milford]

Barney,

Will do as soon as I get home today. I'll let you know.

Thanks

[Ronnie]

As Barney said, check the fluid level, but be sure to follow the instructions on the front side of the reservoir that say:

"FILL ONLY AFTER APPLYING BRAKE PEDAL 25 TIMES WITH IGNITION OFF." Overfilling will result if these instructions are not followed.

[padgett]

The Teeves brake is really two systems that can be treated independantly, the boost system and the ABS system.

If the boost system fails both lights will turn on (without boost the ABS turns off) it does not indicate a ABS failure. The only time you will see the red light alone is if the parking brake is on.

The brake test is more a measure of the accumulator and POST. It does need both lights out to start.

You cannot troubleshoot the boost system with the brake computer, it handles the ABS functions only.

For a real understanding see section 5E and 5E1 in the factory service manual. The online manual for an 89 can be used, it is essentially the same here as for an 88. (ALDL pins are different though).

The boost system must be troubleshot electrically: a failing brake relay, pressure switch, motor, or wiring will cause the symptoms you noted.

Keep in mind that the brake system is a critical safety element. If you are uncertain about it, do not drive until someone is.

[Guest Greg Ross]

Quote

"there is documentation indicating the brake system was checked out recently by a qualified mechanic, and everything was fine"

Keith,

Where Reattas are concerned, I would have to say Teves Brake Systems are about the only exception to the usual adage;

"If it ain't broke, don't fix it"

I also tend to lean toward the suspicious side, if a Mechanic was going over the system, why?

Was it recently flushed? that, as you'll come to realize is "the" most important element of "preventative maintenance" on these systems.

Reliability in a hydraulic system depends on two things, clean fluid and minimal moisture. Both deteriorate with time.

A qualified mechanic is also not necessarily the easy solution to Teves system problems. These systems are quite complex and without first hand experience your typical mechanics have to read and rely on Service Manuals the same as you or I. You're going to find the depth of experience here very valuable in sorting this out.

[Guest Keith_Milford]

Okay, boys and girls; here are the results of Barney's simpified test. The pump takes 30 seconds to go off after turning on the key. As I understand it, this is good. Then, it takes two pumps of the brake for the pump to come back on. Apparently, this is not good. From this, I gather that I at least have a problem with the accumulator, even though it looks brand new. If so, what is the fastest way to get one of these things? Having this beautiful car sitting in my driveway like an overgrown yard sculpture is pure torture. I went to gmpartsonline, but for some reason, I could not get the part to go into the "shopping basket". Do I need to call to order it? What say you all?

[Barney Eaton]

Go to www.gmpartsdirect.com

The part number is 25528382

[Guest Keith_Milford]

Done. Any idea what turn-around time I can expect?

[Vincent Vega]

It's usually 3 days ground. Business days. Sat Sun don't count.

[Guest William Vernon]

It took 13 business days for me. Look at wvernon ABS brake test results thread below. GM Parts Direct ordered Monday, May 19th, received Wednesday June 4th (17 days). $137.25 total cost. Ordered a spare from Auto Parts Giant Tuesday May, 27th and will receive Friday June, 6th (11 days). $132.49 total cost. So Auto Parts Giant was faster and less expensive in my case. Just don't bother trying to call about the order status because you will be hung up on after waiting on hold for 15 minutes (multiple times )

[Guest Keith_Milford]

Ugh, that is brutal. I'm calling my mechanic to see if he can work any magic to get one faster. Couldn't hurt to have a spare. Anybody got a working one they want to UPS to me. I can email a shipping label; just provide an approx. weight. Since replacement looks pretty simple, shouldn't be a problem just swapping out when the new one gets here.

[Guest tomt]

FYI:

It was a next day item through my Buick dealer in the Chicago metro area. Price was $180. You might find that quicker. If you have one, I always recommend a free standing Buick dealer, essentially not part of a group of dealers under the same ownership and who sells only Buick parts. I have found many unusual parts to be in stock, like the blower module etc.

Tom T

[Guest Greg Ross]

Keith,

I don't have a spare to offer you, but

You could pay the premium/ full List and go to your local neighborhood GM Dealer, probably have it overnight.

Installation is simple but be sure to de-energize it first. The accumulator is pressurized to approx. 2500 psi and that would take your hand off if you attempted to remove it when pressurized.

Key off, pump the brake pedal until its' hard, then r & r the accumulator.

[Ronnie]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith_Milford</div><div class="ubbcode-body">Ugh, that is brutal. I'm calling my mechanic to see if he can work any magic to get one faster. Couldn't hurt to have a spare. Anybody got a working one they want to UPS to me. I can email a shipping label; just provide an approx. weight. Since replacement looks pretty simple, shouldn't be a problem just swapping out when the new one gets here. </div></div>

Did you see this? It could possibly be new as he changed over to a different system.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Re: wvernon ABS brake test results

steakneggs

Member

I have an '88 accumulator I'll sell for $10 plus shipping. PM me. Steak

</div></div>

[Guest Keith_Milford]

That's hilarious. Just before I read this, I was on the phone with my mechanic, and his exact words were "those things are dangerous; they'll take your damn hand off. I don't know what GM was thinking when they decided to use that system". Anyway, he just called back and said he can have one this afternoon-$127! I'm all over it.

[Ronnie]

You're welcome.

[Guest Keith_Milford]

Sorry, didn't mean to slight anybody. While in the middle of typing a post, deal with appointments, and field calls from my mechanic and his supplier, your post slipped in. Thank you for the lead. I had seen this post before, and since he didn't respond to the guy who asked if it was new, I assumed it wasn't.

[Guest Keith_Milford]

One more question, please. I did notice, as I was doing the brake tests, that the brake fluid is overfilled about 1/4" or more above the fill mark. Could this be the gremlin that caused the accumulator failure? Seems kind of innocuous to cause that much damage.

[Booreatta]

well did you get your part, did it fix your problems? Keep us posted

[Guest Keith_Milford]

Have to stop by and pick up the part on my way home from work today. Should be able to install it tonight, and I'll let you all know how that turns out. Any opinions regarding my question about the overfilled brake reservoir?

Thanks

[Ronnie]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith_Milford</div><div class="ubbcode-body">One more question, please. I did notice, as I was doing the brake tests, that the brake fluid is overfilled about 1/4" or more above the fill mark. Could this be the gremlin that caused the accumulator failure? Seems kind of innocuous to cause that much damage. </div></div>

Overfilling would not cause the accumulator to go bad. However, I do recommend removing the excess fluid.

The rubber bladder inside the accumulator is what goes bad. Like any other rubber part in your car, it will deteriorate and wear out. How long it will last depends on the length of time it has been in service and the number of repetitions of expanding and contracting it has been subjected to. The conditions of the brake fluid may play some part in how long it will last also.

I consider the accumulator a wear item that normally needs replacing at some point in the life of the car.

[Barney Eaton]

I have heard several people say the bladder inside the accumulator fails, and I don't know if they are speaking from experience or just repeating what some other Reatta owner said.

I have cut an accumulator apart and the rubber bladder is robust. It has to be because it has about 750 psi behind it as charged at the factory. When the pump forces brake fluid into the lower cavity and that further compresses the nitrogen to 2400 psi. That bladder must be tough.

What happens in almost all cases......the nitrogen slowly depletes (is many cases it has taken 15-20 years.)

Without the nitrogen charge on the back side the accumulator just will not work.

[Richard S]

When I picked up my reman Teves in LA, Sam showed me an accumulator he cut in half. Barney is right that the bladder is pretty thick, but the one I was shown was torn. There are really no other moving parts to fail, so it is either the bladder or a pinhole from which the nitrogen leaks out.

[Ronnie]

When I cut my old accumulator open the bladder had torn.

[Booreatta]

that why the accumulators fail the brake fluid penetrates the membrane and the nitrogen charge escapes and the bulb fills with fluid. presto no pressure to the brakes.

[Guest Keith_Milford]

Well, friends and neighbors, I am back in the saddle. Picked up the part on my way home, and had no problem installing it, despite all the dire warnings (thanks to all the help and info available here-thank you, Chuck, for the last minute detailed instructions). Pump turns off in 30 seconds, kicks back on after 5 pedal pumps, and red light is off. I guess the accumulator that was on it was just defective, because I know it was less than a year old, and had less than 1k miles on it. So, now I'm driving, but still need to figure out how to get the yellow light to go off. I will run the complete brake test this weekend, and report back here. Hopefully, you all can help me resolve that problem, also. Thank you again.

[padgett]

If just the yellow light, that is the ABS system and you will need to pull the codes. Just be aware that they are more in the nature of guidelines than reality, when the insulation went on the driver's side on my 88, the code pointed to the passenger side.

[DAVES89]

With the cars of our vintage, it will be more likely that the front wheel sensors are bad. What happens is the insulation goes bad and moisture gets into the cable, causing a false reading of failure. The sensors and leads are on one molded cable and can be replaced. You can buy them from Jim Finn or if you are so motivated, go to a u-pick yard and do it youself. It is not very difficult. It is a snap electrical connection on top, but you must pry it out of the hub bracket down by the wheel.

If you call a salvage yard to pull for you they are more likely to sell you the hub assembly with the leads attached.

As Reattas are so scarce I just go to the Cadillac section of the u-pick yard and look for 88-90 DeVilles, Eldorado, Fleetwood,Seville. Just look under the hood for the accumulater ball and it will have the right leads.

[Guest Keith_Milford]

Good info; I'll file it away for my frequent Pull-a-Part adventures. I did try a panic stop this AM at about 45 mph. Got some pretty decent tire squeal and didn't really notice any chatter or pedal push-back. Suggestions? Should I go ahead with the specified brake test, or would that not provide any helpful info at this point?

[Vincent Vega]

Brake test will confirm the boost system is working. As Padgett says. Pull the ABS codes.

[padgett]

If the yellow light is on, the ABS is disabled and the wheels will lock.

[Guest Keith_Milford]

Although I am fairly mechanically proficient, I am definitely electrically deficient. Please point me in the right direction for pulling ABS codes. I do have the 88 service manual, but when I look at the electrical sections, I have a synapse misfire and end up staring off into space. Then I have a beer and move on to something else.

[Ronnie]

Press the upper-left button on the outside of the CRT to enter Climate mode. Press and hold the OFF and WARM buttons. After a few seconds the CRT will enter diagnostics mode. Have paper and pencil handy to write down the codes.

[padgett]

Unfortunatelly you cannot pull ABS codes that way, you must use a much cruder technique.

With the key off, jumper pins A and G (1988) or A and H (1989-1990) on the ALDL. Turn the key to "RUN". Count the flashes of the ABS lamp - they will be in two elements, the first digit, a pause, and the second digit.

Now pull and reapply the jumper while leaving the key on to read the second code and so forth. There may be up to seven codes stored. The ABS light will stay on steady when there are no more codes.

To repeat from the start, cycle the key from Run to Off and Back. After all codes have been displayed, driving the car will clear them.

See pages 5E1-8 and 9 in the online 1989 service manual.