94 strange ASR problem
Thread Starter
Instructor
Joined: Dec 2009
Posts: 189
Likes: 0
From: New Jersey
94 strange ASR problem
Today I took the 94 out for a drive and when I first fired it up I noticed the ASR Off light illuminated I figured maybe I accidentally hit the button turned it back on and went on my way. After shutting the car off later and starting it again the ASR Off light was illuminated again. I tested this multiple times and the ASR seems to be off now by default when the car is started. If I hit the button it turns back on but if I hit the button again it will not always shut back off sometimes I have to hit the button multiple times before it will turn back off. I tested the ASR and it seems to be working fine when I mash the gas pedal. I've never had a problem with the ASR button before and it was never off by default when the car is first started. Also the service ASR light is not on.
Any ideas?
Thanks
Any ideas?
Thanks
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
It looks like the EBTCM (brake computer) is what the switch and light connect to. That unit could be the problem. However the brake computer is linked to the PCM as well as numerous items on the car. That system get input from many different sources.
If I were to take a first educated guess or a start, the EBTCM might be my first guess. Substitution is probably the easiest and quickest method to find or eliminate modules or items. But having one laying around just to try is probably not the case.
For this problem, a FSM is definitely a necessity to have to see what going on and what is related. (Section 5E2). If the EBTCM is not bad, it could be a impossible repair without the FSM.
Just as a suggestion, I would go into the on board diagnostics and clear the codes on all modules especially the 9.0 module (EBTCM). Removing the battery cable will not clear module 9.
If I were to take a first educated guess or a start, the EBTCM might be my first guess. Substitution is probably the easiest and quickest method to find or eliminate modules or items. But having one laying around just to try is probably not the case.
For this problem, a FSM is definitely a necessity to have to see what going on and what is related. (Section 5E2). If the EBTCM is not bad, it could be a impossible repair without the FSM.
Just as a suggestion, I would go into the on board diagnostics and clear the codes on all modules especially the 9.0 module (EBTCM). Removing the battery cable will not clear module 9.
Safety Car
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
It looks like the EBTCM (brake computer) is what the switch and light connect to. That unit could be the problem. However the brake computer is linked to the PCM as well as numerous items on the car. That system get input from many different sources.
If I were to take a first educated guess or a start, the EBTCM might be my first guess. Substitution is probably the easiest and quickest method to find or eliminate modules or items. But having one laying around just to try is probably not the case.
For this problem, a FSM is definitely a necessity to have to see what going on and what is related. (Section 5E2). If the EBTCM is not bad, it could be a impossible repair without the FSM.
Just as a suggestion, I would go into the on board diagnostics and clear the codes on all modules especially the 9.0 module (EBTCM). Removing the battery cable will not clear module 9.
If I were to take a first educated guess or a start, the EBTCM might be my first guess. Substitution is probably the easiest and quickest method to find or eliminate modules or items. But having one laying around just to try is probably not the case.
For this problem, a FSM is definitely a necessity to have to see what going on and what is related. (Section 5E2). If the EBTCM is not bad, it could be a impossible repair without the FSM.
Just as a suggestion, I would go into the on board diagnostics and clear the codes on all modules especially the 9.0 module (EBTCM). Removing the battery cable will not clear module 9.
Start here.I guess I'm the weirdo who has both a EBTCM and the ABS/ASR hydraulic unit just laying around....
Thread Starter
Instructor
Joined: Dec 2009
Posts: 189
Likes: 0
From: New Jersey
I haven't had a chance to look at my service manual yet but I did put the car in diagnostic mode there were no codes but I cleared module 9 anyway. One thing I noticed was every time I hit eng met to clear the codes on module 9 there was a clicking noise coming from the dash behind the ASR button. After clearing module 9 ASR would be off no matter if it were on or off before I hit Eng met to clear the codes.
Could the clicking noise mean there may be an issue with the ASR button itself or is this normal when clearing module 9?
I'm going to look at my service manual later today when I get home and see what else I can check before buying a used ebtcm and trying that.
Could the clicking noise mean there may be an issue with the ASR button itself or is this normal when clearing module 9?
I'm going to look at my service manual later today when I get home and see what else I can check before buying a used ebtcm and trying that.
Thread Starter
Instructor
Joined: Dec 2009
Posts: 189
Likes: 0
From: New Jersey
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
One thing I noticed was every time I hit eng met to clear the codes on module 9 there was a clicking noise coming from the dash behind the ASR button. After clearing module 9 ASR would be off no matter if it were on or off before I hit Eng met to clear the codes.
Could the clicking noise mean there may be an issue with the ASR button itself or is this normal when clearing module 9?
I'm going to look at my service manual later today when I get home and see what else I can check before buying a used ebtcm and trying that.
Could the clicking noise mean there may be an issue with the ASR button itself or is this normal when clearing module 9?
I'm going to look at my service manual later today when I get home and see what else I can check before buying a used ebtcm and trying that.
You might try disconnecting the battery for a couple minutes and see if the ASR problem clears. It's a long shot but you never know when a logic gate or line will hang and may need a reset. I would try all the simple (and stupid) stuff I could think of before buying new boxes and parts.
That’s really a stretch. I doubt if the alternator is part of the ASR problem. In all likely hood the regulator in the alternator quit and it's not putting out any charging voltage. I would pull it and get it checked, then go from there.
Thread Starter
Instructor
Joined: Dec 2009
Posts: 189
Likes: 0
From: New Jersey
Looks like in the next day or two I'll be pulling off the alternator and getting it waranteed. I checked out my FSM and followed the chart for the ASR light always being on and the next step after what I've tried so far is to disconnect the ebtcm and turn key on and check for the ASR off indicator and that will indicate a short to ground or a bad ebtcm so I'll be checking that also. I'll have the battery disconnected when I change the alternator so maybe I'll get lucky with the ASR light. I'll post results when I find them.
Thanks for the input so far guys
Thanks for the input so far guys
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Thread Starter
Instructor
Joined: Dec 2009
Posts: 189
Likes: 0
From: New Jersey
I know its been a while since I posted this but just wanted to update.
Problem solved!
Replaced the alternator that died right after the ASR problem started and charged up the battery and all is well again. I had the battery disconnected for a few days maybe that helped or maybe low voltage caused a problem, not sure but its working as it should again.
Problem solved!
Replaced the alternator that died right after the ASR problem started and charged up the battery and all is well again. I had the battery disconnected for a few days maybe that helped or maybe low voltage caused a problem, not sure but its working as it should again.
