Service Stabilty System light is on
#1
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Service Stabilty System light is on
I have had the SSS light on since I bought the car. I am finally getting around to fixing it.
During normal driving, almost all the warnings lights are on, as shown in this video, but in some rare times, all those lights will go off, and the LOW TRAC light will come on (which is normally not on). During those times, if I press the accelerator, the car wants to go, but the brakes are applied. It is the weirdest feeling. You can bypass it by holding the brake pedal down just enough for the car to know it is pressed, and you can continue to drive with the brake depressed. Then after any given amount of time, the LOW TRAC light will go off, and all the other lights will DING back on and everything is normal.
I currently drive with no traction control or ABS.. not the safest. :?
I brought the car to the dealer for a TECH2 scan, they did it for free since they know I am trying to track this problem down without their help. It showed a history of 3 non-reading wheel speed sensors. LF, RF, and RR. However, during the road test, only one of the WSS was not working, displaying 0 mph, it was the RR.
The mechanic told me to go home and test the WSS. He said if I took off the wheel, and put a multimeter on the WSS on the hub, that when I spin the wheel, it should produce a small voltage.
I have not done this cuz 1. I think its BS, and 2. its been raining 24/7 here and there is no room in the garage. Why are my WSS'* working so intermediately? He cleared all the codes.
What would case the WSS'* to be so erratic?
During normal driving, almost all the warnings lights are on, as shown in this video, but in some rare times, all those lights will go off, and the LOW TRAC light will come on (which is normally not on). During those times, if I press the accelerator, the car wants to go, but the brakes are applied. It is the weirdest feeling. You can bypass it by holding the brake pedal down just enough for the car to know it is pressed, and you can continue to drive with the brake depressed. Then after any given amount of time, the LOW TRAC light will go off, and all the other lights will DING back on and everything is normal.
I currently drive with no traction control or ABS.. not the safest. :?
I brought the car to the dealer for a TECH2 scan, they did it for free since they know I am trying to track this problem down without their help. It showed a history of 3 non-reading wheel speed sensors. LF, RF, and RR. However, during the road test, only one of the WSS was not working, displaying 0 mph, it was the RR.
The mechanic told me to go home and test the WSS. He said if I took off the wheel, and put a multimeter on the WSS on the hub, that when I spin the wheel, it should produce a small voltage.
I have not done this cuz 1. I think its BS, and 2. its been raining 24/7 here and there is no room in the garage. Why are my WSS'* working so intermediately? He cleared all the codes.
What would case the WSS'* to be so erratic?
#2
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Corroded connections would be the most common cause for intermittents such as that. It'* possible that the WSS could generate a small voltage, but whether it would be enough to read would be the question. You may want to try resistance instead, and see if that varies during the spin. A bad sensor in the hub could be causing all of your problems. I'd start by replacing just that one, and trying contact cleaner on the others.
#3
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There are a few possibilities. The WSS as I recall generates pulses and therefore, due to the type of device I understand them to be, will generate a small voltage with each pulse. It'* very possible that you won't see this with a DMM (Digital Multimeter) due to the lag. Your best bet would be a "traditional" meter with a needle.
These sensors are solid state devices. As such, a number of things can occur. It isn't by any means out of the realm of possibility that they can be intermittent. As Archon mentions, connections are very likely, but don't discount a failing (intermittent) sensor either.
Have a look here for examples of speed sensors:
http://en.wikipedia.org/wiki/Hall_effect_sensor
http://www.mcselec.com/index.php?opt...=106&Itemid=57
These sensors are solid state devices. As such, a number of things can occur. It isn't by any means out of the realm of possibility that they can be intermittent. As Archon mentions, connections are very likely, but don't discount a failing (intermittent) sensor either.
Have a look here for examples of speed sensors:
http://en.wikipedia.org/wiki/Hall_effect_sensor
http://www.mcselec.com/index.php?opt...=106&Itemid=57
#4
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Haro, I'd check your ABS module and make sure you don't have any corrosion. Seeing 3 sensors out of whack sounds really bizarre. I know there was an issue with the 2001 Auroras erroneously displaying "Service Stability System" and that a flash of the PCM cured the problem, but I'm not sure if the early Bonnevilles had the problem too.
I would check the ABS module connector for possibly corrosion and also check the TSBs (if you have access to them ) to see if the early model Bonnevilles had an issue with the software on them too. I think that TSB for the Aurora came out in late 01 or 02, so that might be a place to start.
I would check the ABS module connector for possibly corrosion and also check the TSBs (if you have access to them ) to see if the early model Bonnevilles had an issue with the software on them too. I think that TSB for the Aurora came out in late 01 or 02, so that might be a place to start.
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[quote="CFoote"]
I would check the ABS module connector for possibly corrosion and also check the TSBs (if you have access to them ) to squote]
Where is the ABS module located?
I would check the ABS module connector for possibly corrosion and also check the TSBs (if you have access to them ) to squote]
Where is the ABS module located?
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I know its old, and you already posted to it, but may refresh something
http://www.bonnevilleclub.com/forum/...ability+sensor
http://www.bonnevilleclub.com/forum/...ability+sensor
#7
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Originally Posted by imidazol
Where is the ABS module located?
See here.
http://www.alldatadiy.com/alldata/AF...42970/14464382
#8
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I checked for anything from the WSS'* with my analog multimeter. I could not get a reading in AC, DC or Ohm'*... Maybe I was just not doing it right, but the FSM says I should see 850-1350 Ohms of resistance across the WSS. When I spin it by hand, I should see 100 mV of AC voltage. I saw nothing, but again, it probably could not pick it up.
Upon further reading, I read that:
An unprogrammed EBCM will result in the following:
-Inoperative or poorly functioning DRP/ABS/TIM/VSES/TIM/VES (if equipped)
-Set DTC-C1248 EBCM Turned On the Red Brake Warning Indicator
-Set DTC-C1255m3 EBCM Internal Malfunction
I am having problems with at least two of the following. I think my next step would be to install a new EBCM and have the dealer program it. Thoughts?
Upon further reading, I read that:
An unprogrammed EBCM will result in the following:
-Inoperative or poorly functioning DRP/ABS/TIM/VSES/TIM/VES (if equipped)
-Set DTC-C1248 EBCM Turned On the Red Brake Warning Indicator
-Set DTC-C1255m3 EBCM Internal Malfunction
I am having problems with at least two of the following. I think my next step would be to install a new EBCM and have the dealer program it. Thoughts?
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In your original post, you mentioned that there was one sensor which did seem to be working (LR) according to the scan. I'm curious as to whether you measured this one with your meter? If you are concerned your technique may not be correct, this might help rule out a problem here.
I looked at the FSM and saw the same information for resistance and voltage measurements. If you aren't seeing either of these, it strongly suggests an open circuit. Are you measuring right at the sensor or did you disconnect at the EBCM and measure there?
I looked at the FSM and saw the same information for resistance and voltage measurements. If you aren't seeing either of these, it strongly suggests an open circuit. Are you measuring right at the sensor or did you disconnect at the EBCM and measure there?
#10
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according to the scan, the RR was the one NOT working, the other 3 were. However, all of the other WSS'* did have DTC history codes. I can't see the WSS'* being intermediate.
I tested the WSS'* on both rears, and didnt get anything from either. I am going to try again today just to double check.
I tested the WSS'* on both rears, and didnt get anything from either. I am going to try again today just to double check.