ANTILOCK light on - no codes
#1
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ANTILOCK light on - no codes
1999 Pontiac Bonneville 3.8L NA 167,000 miles.
Long story short -
Got cut off going home the other day and hit the brakes hard. The antilock worked as it should. However, the LF brake line (The steel one) ruptured. I limped it back home (fortunately not far). and the next day replaced the brake line and bled the LF. The brakes now work fine, nice firm pedal no pulling on either side.
Next day the ANTLOCK light came on, so today I took it to the parts store and they scanned for ABS codes. No codes were stored. Yet the light is on steady and still is.
Can someone point me in a direction to start checking or give a reason for this? I've checked the fuses and they appear to be OK.
Thanks!
Long story short -
Got cut off going home the other day and hit the brakes hard. The antilock worked as it should. However, the LF brake line (The steel one) ruptured. I limped it back home (fortunately not far). and the next day replaced the brake line and bled the LF. The brakes now work fine, nice firm pedal no pulling on either side.
Next day the ANTLOCK light came on, so today I took it to the parts store and they scanned for ABS codes. No codes were stored. Yet the light is on steady and still is.
Can someone point me in a direction to start checking or give a reason for this? I've checked the fuses and they appear to be OK.
Thanks!
#2
Retired
You probably have air in the ABS unit. You need to find a shop that can do the GM ABS bleed procedure. Only high end scanners (SnapOn'*) and GM Tech 2'* can do this.
Or go find a big gravel parking lot, get some speed, slam on the brakes. Trick is to get the ABS motors to activate and open the valves. This might take a few hard brakes to get it to bleed. It did work on my 2002 S10.
Or go find a big gravel parking lot, get some speed, slam on the brakes. Trick is to get the ABS motors to activate and open the valves. This might take a few hard brakes to get it to bleed. It did work on my 2002 S10.
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#4
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Well, I finally got the opportunity to take the car out to a place to do some sliding around. Had some fun locking up the brakes and sliding, but that didn't do a bit of good. Antilock never engaged, light is still on, no change.
Fast forward a couple of days .....
I was driving home from dropping my son off for practice, when I noticed that the antilock light was NOT on. One of the things that makes you go Hmmmmm.....
When I got home, I shut the engine off. I thought to myself "I wonder if the light will stay off?" So, I restarted the car. The light came on and stayed on. Oh well ....
I thought "Let'* try that again", so I shut the engine off, waiting a few seconds, and restarted the car. The ABS light was off. Hmmmm...
A failing relay perhaps? I checked the picture I have the shows the relays in the underhood section, but while there are ABS fuses, no relay is listed. So I tried my Google-fu to see if it might be located elsewhere (If it even exists). I could not find the location, but I did find pleny of vendors willing to sell me the relay or harness for the relay.
My question is: Does anyone know where the ABS relay is on a 1999 Bonneville, if it even exists?
Fast forward a couple of days .....
I was driving home from dropping my son off for practice, when I noticed that the antilock light was NOT on. One of the things that makes you go Hmmmmm.....
When I got home, I shut the engine off. I thought to myself "I wonder if the light will stay off?" So, I restarted the car. The light came on and stayed on. Oh well ....
I thought "Let'* try that again", so I shut the engine off, waiting a few seconds, and restarted the car. The ABS light was off. Hmmmm...
A failing relay perhaps? I checked the picture I have the shows the relays in the underhood section, but while there are ABS fuses, no relay is listed. So I tried my Google-fu to see if it might be located elsewhere (If it even exists). I could not find the location, but I did find pleny of vendors willing to sell me the relay or harness for the relay.
My question is: Does anyone know where the ABS relay is on a 1999 Bonneville, if it even exists?
#5
Senior Member
Posts like a Turbo
I've had the same abs/traction control light appear on certain days, esp when it'* getting colder, can turn car off and start back up and light usually goes out. no codes, have also unplugged connecter and back in again at wheels and ABS unit.
I think it may have something to do with either the little abs motor has not ran in a long time or module getting weak... if you get abs motor to kick in, it just lasts for a second and abs light comes on, no codes.. turn off and restart.. light is out until next time or cold morning
I think it may have something to do with either the little abs motor has not ran in a long time or module getting weak... if you get abs motor to kick in, it just lasts for a second and abs light comes on, no codes.. turn off and restart.. light is out until next time or cold morning
#6
Senior Member
True Car Nut
there are a bunch of relays above the passengers foot cover, but good luck figuring out what does what. nothing on the cover, the manual says "contact dealer"(right)
#8
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Well the saga continues:
I suspected that there could maybe, just possibly, might just be a ground issue happening. I measured the ground connection from the wire on the front of the pump to ground, and found that it was unreliable, and varied in resistance to ground. So what I did was this:
I ran a 14 gauge wire from the negative battery terminal to the bracket that holds the ABS pump. Then I also ran a wire from the bracket to the ground post on the front of the pump.
While this did not completely resolve the issue, things have improved. Now when I first start the car in the morning, the ABS light comes on and stays on. I let the car run for 15-20 seconds, then shut it off and restart. The ABS light turns off, and does not come back on during the day, even after sitting at work in the parking lot for 9 hours. During the day, no matter how much or how little I use the car, the ABS light will remain off for the duration of the day and into the night. After sitting overnight in the driveway, I need to do the start-run-stop-restart again. When the light is off, the ABS operates normally (It was a little fun to test test this out). If the light is on, the ABS system does not function at all.
I suspected that there could maybe, just possibly, might just be a ground issue happening. I measured the ground connection from the wire on the front of the pump to ground, and found that it was unreliable, and varied in resistance to ground. So what I did was this:
I ran a 14 gauge wire from the negative battery terminal to the bracket that holds the ABS pump. Then I also ran a wire from the bracket to the ground post on the front of the pump.
While this did not completely resolve the issue, things have improved. Now when I first start the car in the morning, the ABS light comes on and stays on. I let the car run for 15-20 seconds, then shut it off and restart. The ABS light turns off, and does not come back on during the day, even after sitting at work in the parking lot for 9 hours. During the day, no matter how much or how little I use the car, the ABS light will remain off for the duration of the day and into the night. After sitting overnight in the driveway, I need to do the start-run-stop-restart again. When the light is off, the ABS operates normally (It was a little fun to test test this out). If the light is on, the ABS system does not function at all.
#9
Senior Member
Posts like a Turbo
Bret, same deal here.. exactly...
Well the saga continues:
I suspected that there could maybe, just possibly, might just be a ground issue happening. I measured the ground connection from the wire on the front of the pump to ground, and found that it was unreliable, and varied in resistance to ground. So what I did was this:
I ran a 14 gauge wire from the negative battery terminal to the bracket that holds the ABS pump. Then I also ran a wire from the bracket to the ground post on the front of the pump.
While this did not completely resolve the issue, things have improved. Now when I first start the car in the morning, the ABS light comes on and stays on. I let the car run for 15-20 seconds, then shut it off and restart. The ABS light turns off, and does not come back on during the day, even after sitting at work in the parking lot for 9 hours. During the day, no matter how much or how little I use the car, the ABS light will remain off for the duration of the day and into the night. After sitting overnight in the driveway, I need to do the start-run-stop-restart again. When the light is off, the ABS operates normally (It was a little fun to test test this out). If the light is on, the ABS system does not function at all.
I suspected that there could maybe, just possibly, might just be a ground issue happening. I measured the ground connection from the wire on the front of the pump to ground, and found that it was unreliable, and varied in resistance to ground. So what I did was this:
I ran a 14 gauge wire from the negative battery terminal to the bracket that holds the ABS pump. Then I also ran a wire from the bracket to the ground post on the front of the pump.
While this did not completely resolve the issue, things have improved. Now when I first start the car in the morning, the ABS light comes on and stays on. I let the car run for 15-20 seconds, then shut it off and restart. The ABS light turns off, and does not come back on during the day, even after sitting at work in the parking lot for 9 hours. During the day, no matter how much or how little I use the car, the ABS light will remain off for the duration of the day and into the night. After sitting overnight in the driveway, I need to do the start-run-stop-restart again. When the light is off, the ABS operates normally (It was a little fun to test test this out). If the light is on, the ABS system does not function at all.
#10
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Thread Starter
Well, another chapter (and hopefully the last). On Wednesday, it was raining a little, just enough to make the street slick. So, just before I got to my driveway, I locked up the brakes on purpose (the ABS light was off, no other traffic around) and the ABS operated normally. I pulled into the driveway and locked the car for the night.
Next morning I went to the car to go to work, started the car, fully expecting the ABS light to stay on until I stopped and restarted the car. To my surprise the ABS light turned off without restarting the car. I thought that it may be a fluke.
Next day, same thing. ABS operated just like it was supposed to. And again this morning (now 3 times in a row) all was as it should be. So it would seem that:
The added ground got me to an intermittent condition that I could work with. Before the added ground, the ABS light was on all the time and the ABS would never activate.
The last ABS activation appears to have cleared whatever was setting the light.
Let'* hope it stays this way.
Next morning I went to the car to go to work, started the car, fully expecting the ABS light to stay on until I stopped and restarted the car. To my surprise the ABS light turned off without restarting the car. I thought that it may be a fluke.
Next day, same thing. ABS operated just like it was supposed to. And again this morning (now 3 times in a row) all was as it should be. So it would seem that:
The added ground got me to an intermittent condition that I could work with. Before the added ground, the ABS light was on all the time and the ABS would never activate.
The last ABS activation appears to have cleared whatever was setting the light.
Let'* hope it stays this way.