BAS/ASR Light on
#31
07-29-2008, 09:19 AM
RE: BAS/ASR Light on
Sorry, I perhaps did not make myself clear.
When I drive away, after a couple of minutes the ASR light comes on, not the triangle light, and sometimes even the ABS light comes on. However, the triangle light in the speedo dial comes on if I force a wheel spin.
The ASR light always comes on whereas the ABS light only comes on occasionally
When I drive away, after a couple of minutes the ASR light comes on, not the triangle light, and sometimes even the ABS light comes on. However, the triangle light in the speedo dial comes on if I force a wheel spin.
The ASR light always comes on whereas the ABS light only comes on occasionally
#32
07-30-2008, 01:31 AM
RE: BAS/ASR Light on
Hi,
Not the usual failure signature.
OK at ignition ON so startup checks OK.
Still OK after moving off (more checks),
OK for a period of time. How long. 1 min, 10 mins, 100 mins?
+ System working corrected when required to do so.
Suspect speed signal implausibility which would possibly be caused by dirt on the sensor tips.
The speed sensors are common to several systems however the ASR and ABS both check continuously to ensure that relative signal from each wheel is within set limits. If not the malfunction lights are illuminated. i.e. Straight road (steering wheel straight) then LH and RH must be within 5% (to allow for one new and one worn tyre on the same axle) rotational speed. Likewise relationship of front to rear rotational speeds must also be within limits but this is sometimes a greater threshold due to intended different tyre sizes front to rear. etc etc. I assume you have not fitted non standard tyre sizes.
I would have expected operation of the system to have been disabled if a warning is given...however maybe I'm incorrect in thinking this?
Dirt builds up on the sensor tips. Remove and wipe clean + ensure electrical connections and wiring are sound and with no corrosion of the connector etc.
The most common failure on these systems is the brake light switch. Are you able to test to determine whether operation of the brakes (i.e. touching/pressing the brake pedal is the initiator for the warning lights to illuminate. If so its the light brake switch. Note 2 circuits. One Normally closed, one normally open so the brake lights may appear to be working fine although the switch signal is faulty.
Could also try a battery disconnect for 10 minutes or so to reset all modules but confidence of this working very low. (Plus ensure you have your radio security code and reset your steering sensor after disconnect)
Stuart.
Not the usual failure signature.
OK at ignition ON so startup checks OK.
Still OK after moving off (more checks),
OK for a period of time. How long. 1 min, 10 mins, 100 mins?
+ System working corrected when required to do so.
Suspect speed signal implausibility which would possibly be caused by dirt on the sensor tips.
The speed sensors are common to several systems however the ASR and ABS both check continuously to ensure that relative signal from each wheel is within set limits. If not the malfunction lights are illuminated. i.e. Straight road (steering wheel straight) then LH and RH must be within 5% (to allow for one new and one worn tyre on the same axle) rotational speed. Likewise relationship of front to rear rotational speeds must also be within limits but this is sometimes a greater threshold due to intended different tyre sizes front to rear. etc etc. I assume you have not fitted non standard tyre sizes.
I would have expected operation of the system to have been disabled if a warning is given...however maybe I'm incorrect in thinking this?
Dirt builds up on the sensor tips. Remove and wipe clean + ensure electrical connections and wiring are sound and with no corrosion of the connector etc.
The most common failure on these systems is the brake light switch. Are you able to test to determine whether operation of the brakes (i.e. touching/pressing the brake pedal is the initiator for the warning lights to illuminate. If so its the light brake switch. Note 2 circuits. One Normally closed, one normally open so the brake lights may appear to be working fine although the switch signal is faulty.
Could also try a battery disconnect for 10 minutes or so to reset all modules but confidence of this working very low. (Plus ensure you have your radio security code and reset your steering sensor after disconnect)
Stuart.
#33
07-30-2008, 01:54 AM
RE: BAS/ASR Light on
Hi Stuart,
Thanks for all the information you have supplied, I will certainly try to sort out the problem. As I said the ASR malfunction light comes on after a couple of minutes, and then after about 5 minutes the ABS malfuntion light comes on, but not every time (ABS). The strange thing is that the ASR triangle warning light comes on if I force a wheel spin. Im sure I will be able to sort this out with all the info that is available on these pages, otherwise it will be another visit to the Merc shop
George
Thanks for all the information you have supplied, I will certainly try to sort out the problem. As I said the ASR malfunction light comes on after a couple of minutes, and then after about 5 minutes the ABS malfuntion light comes on, but not every time (ABS). The strange thing is that the ASR triangle warning light comes on if I force a wheel spin. Im sure I will be able to sort this out with all the info that is available on these pages, otherwise it will be another visit to the Merc shop
George
#34
07-30-2008, 02:37 AM
RE: BAS/ASR Light on
The Yellow Triangle coming on when you force wheel spin indicates that the system is working.
The Yellow Triangle is a warning that you are operating (driving) outside limiting friction conditions and that you need to moderate your driving style.
i.e. The system has intervened and reduced throttle for you.
But I'm sure you already knew that.
You didn't state mileage etc. Had new brake rotors?
Stuart.
The Yellow Triangle is a warning that you are operating (driving) outside limiting friction conditions and that you need to moderate your driving style.
i.e. The system has intervened and reduced throttle for you.
But I'm sure you already knew that.
You didn't state mileage etc. Had new brake rotors?
Stuart.
#35
07-30-2008, 11:21 AM
RE: BAS/ASR Light on
Hi,
The mileage is about 150000 miles, and as far as new brake rotors, that I do
not know, only had the car for 2 yrs.
Just one other thing, after winter storage, the car is only used during the
summer, I had to replace the battery, could this have anything to do with
the problems. I know that it is necessary to turn the steering wheel lock to
lock on the later E models, but does this apply to the the older 126 models
George
The mileage is about 150000 miles, and as far as new brake rotors, that I do
not know, only had the car for 2 yrs.
Just one other thing, after winter storage, the car is only used during the
summer, I had to replace the battery, could this have anything to do with
the problems. I know that it is necessary to turn the steering wheel lock to
lock on the later E models, but does this apply to the the older 126 models
George
#36
07-30-2008, 11:06 PM
RE: BAS/ASR Light on
150,000k miles. The vehicle will have had several rotors. This increases the chances of the sensor tips being dirty.
Battery replace should be unrelated. However as I stated you can disconnect and recoinnect a few minutes later to reset all computers.
Don't know about differences model to model.
Stuart.
Battery replace should be unrelated. However as I stated you can disconnect and recoinnect a few minutes later to reset all computers.
Don't know about differences model to model.
Stuart.
#38
07-24-2022, 10:52 AM
BAS/ASR light
Hey I've just had the speed sensor replaced not long ago and this light is still popping up but only when I press on the brake pedal, I also went and got the car diagnostic and they said the light is due to low voltage. Any thoughts?
Bailey
Bailey
Last edited by Bailey; 07-24-2022 at 10:57 AM.
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