New here....

I own a 2003 Bonneville and I have a problem I'm not sure how to handle.

My Brake / Anti Lock / Trac Off lights go on and off all the time. It seemed in the winter, they were on the entire time. On warm days, they are on and off. On really hot days, they are off most of the time. Very rarely the Trac Off light is just on.

I don't know if it is coincidence but I first noticed this after I was having trouble with an air compressor hooked to my cigarette lighter blowing a fuse. I replaced the fuse and stopped using the compressor. I'm not sure if this is related but I think the problem occurred right after that.

I took it to a GM dealer and they told me that the Electronic Brake Module AND the Brake Module Valve need to be replaced. Those 2 components are expensive and I want to be sure that is the problem. What are the chances of both these things going out? Not just one. And if they said this was the problem...is it safe to say that they are right? I'm worried about spending alot of money and it not being the problem. Would there diagnostics have picked up bad wiring? or bad wheel sensor(s)? or anything else?

These lights come on/off whenever. I don't need to be braking. But if I am, my brake pedal gives a little and makes a weird noise and then the lights come on about 1 second later. So when the lights are on, anti lock is disabled.

Any help would be appreciated...I'm thinking about bringing the car in to another dealer to see what they say.

They are two parts of the same assembly. The dealer likely was basing their diagnosis on a combination of the codes that were pulled, as well as your symptoms. They probably are correct. You can try another dealer or an independent shop for a second opinion.

If you do your own work, you could try replacing them individually and see how it works out. Options are to send a private message to Andrew (Harofreak00) to see if he has good used ones, or there are rebuilders who will rebuild your unit for you for a reasonable price.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Thanks.

The dealer wanted $1,725 for these 2 parts alone but I found the exact same parts at a scrap yard (Buick Lesabre) for $80 total. I'm going to try these parts and see what happens.

Few other questions...
1) I'm skeptical on whether I "shorted" something when I used that air pump using my 12V cigarette lighter in the car. If so, would it have shorted the EBCM? I'm worried that maybe I'll put these other parts in and there is a "culprit" that is going to do the same

2) I've never done this type of work before. I'm guessing when I unhook all those brake lines...the brake fluid is going to drain. So am I right that I'm going to have to basically do a flush/change of the brake fluid after installation of the new parts?

3) Do I need to go to the dealer again after I install the parts from the Buick Lesabre to get codes cleared? or software flashed? etc...? Or will it just plug in and work?

4) Any other advice besides disconnecting the battery?

Appreciate your help!

I doubt that anything that you did with the cigarette lighter affected the EBCM. The fuse is there to not only protect the wiring, but also from a short affecting other circuits.

Right, you'll have to bleed the air out of the system. In addition, after replacing the parts and bleeding, you may want to head out to somewhere like a gravel road where you can hit the brakes hard to activate the ABS. That will help to bleed air out of the system. You may have to bleed the system several times to get the brakes solid.

If the parts are the same, and from a car that has the same features as yours that are controlled by it, you should be all set to go.

Make sure that you have plenty brake fluid. Take a lot of pictures ahead of time in case you forget how things go back together. You may also want to label each of the lines going to the system to be certain they go back where they belong.

And welcome to our little corner of the internet.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Thank you so much!!! You have been extremely helpful! Hopefully this all goes as planned and actually fixes my issue.

Good luck. Let us know.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Well, I replaced the EBCM and EBCV today. I was excited to get back in my car and see if my 3 hrs paid off.....nope. All 3 lights were on and stayed on. PLUS, I now have a "Brake Fluid Low" message that stays on even though I bled the brakes and the brakes feel like they did before the repair. I called the dealer and he said that they need to "program" this part and that is why we are probably getting the lights on still. So they want $100 to do that.

I'm not sure if this is the case for the "Brake Fluid Low" message too or not. Not sure why it's doing that. I even disconnected my battery during the installation and did it after I saw this message to see if I could "clear" any errors.

One with the same part number, from a vehicle with the same accessories and features as yours that are controlled by the EBCM should not have needed programming. On the chance that it needs to be, if you have other dealers in the area, call to see what they charge. Prices can vary widely from dealer to dealer.

The brake level sensor is attached to the side of the fluid reservoir. Check to be certain you didn't knock the connector off, or damage the sensor.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Can I take the sensor off and reconnect without issue? Don't want to lose fluid or have to bleed again if I don't have to.

And yes, same parts replaced what I had. I'll take your advice and call around.

If it needs to be replaced, it can be done without losing much, if any fluid. I broke mine a few years back, and replaced it without any problem.

You could also try posting here, or in general chat to see if someone near you has a Tech II that may be able to program it for you.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Is the sensor actually IN the brake fluid or is this some sort of magnetic sensor that picks up a "float" of some sort that is inside the resevoir? I ordered a new sensor thru Amazon so I'll try that route first but was wondering if there is some sort of "float" inside the resevoir that could be stuck since my brake fluid level did get low (not sure how low) after changing the EBCM/EBCV.

AND, if there is a float, can I suck brake fluid out of the resevoir with a turkey baster to a point where I can see it or how would I "free" it? I couldn't find a picture on the internet anywhere of my resevoir.

I just want to avoid doing any bleeding of the master cylinder or brakes.....again.

Well, I brought my car into the dealer again as they said they needed to "program" my new EBCM. They called me soon after and needed my old part so that they could get numbers off of it to call GM. Apparently GM needs to do something as well to get it to work. So it looks like my problem is solved now. I still have the Brake Fluid Low message with the Brake light on so I'm going to replace the $12 sensor first to see what happens and make my way to the resevoir if that doesn't fix it...

Sorry I'm a little late to this, but I see that you're local to me and I have a scantool capable of pulling ABS codes. Maybe it can help shed light on something?

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WHITE WHINE - 1992 SSE Supercharged 236.26 ci (.040 Over) 15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers & a 10" Alpine Type R Sub, all the watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, Ceramic Coated Ported Exhaust Manifolds, Fan Override, Monroe Reflex struts, red calipers
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser, 3.45 diff and various Camaro suspension bits, LED Taillights

I'm not certain on how exactly the sensor works. I've never delved into it. You should be able to replace it without losing much fluid.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Ok, I replaced the sensor and that wasn't the problem. It was only $7 or so on Amazon so I made a premature purchase. I should have just pulled the sensor and started the car up to see if it still read "Low Brake Fluid". Turns out my float must have been stuck in the brake reservoir. I tapped hard on the bottom side of the reservoir with the sensor out and that seemed to solve the problem.