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Emergency Brake Light

  • Thread starter Thread starter extozy
  • Start date Start date Jul 28, 2004

extozy

New Member
Sep 7, 2003
93
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0
Longview, TX
Jul 28, 2004
#1
  • Jul 28, 2004
  • #1
my e-brake light stays on in my car, i have a 1990 LX 5.0 Coupe, and when i flip on the brights forward it goes off, but when i pull it backwards they don't come on..? whats the deal with this?
 
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
Jul 28, 2004
#2
  • Jul 28, 2004
  • #2
First thing I'd do is to check the condition of your rear brakes. Most likely they need replaced and the light is staying on because of that or the other option is that the cables are froze.
 
O

oldman

New Member
Nov 6, 2002
43
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Austin, Texas
Jul 28, 2004
#3
  • Jul 28, 2004
  • #3
If you are low on brake fluid, the light comes on. Check.
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
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0
Mill Creek, WA
Jul 29, 2004
#4
  • Jul 29, 2004
  • #4
ss93cobra said:
First thing I'd do is to check the condition of your rear brakes. Most likely they need replaced and the light is staying on because of that or the other option is that the cables are froze.
Click to expand...

That light has nothing to do with either condition of the rear brakes or if the parking brake cables are froze.

The reasons it would be on are either low brake fluid in the master cylinder, parking brake lever is pulled up (or switch stuck), or some other mystery electrical problem.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Jul 29, 2004
#5
  • Jul 29, 2004
  • #5
im with Adam - and it sounds like an electrical gremlin.
 

_jb_

New Member
Mar 4, 2004
808
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0
Michigan, Berrien County
Jul 29, 2004
#6
  • Jul 29, 2004
  • #6
Yeah, I would check the ground because ground wires can throw electrical stuff really off.
 
S

ss93cobra

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Apr 10, 2002
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Wilmington NC
Jul 30, 2004
#7
  • Jul 30, 2004
  • #7
89MUSTANGGX-So, when it happened to my wife's car and I changed the rear shoes and the light went off, it was just coincidence? Just because it doesn't make sense doesn't mean its not possible.
 

BlackGT89

Member
Dec 16, 2002
774
8
18
Huntsville, AL
Jul 30, 2004
#8
  • Jul 30, 2004
  • #8
Do your brakes feel mushy ? Have you had a leak anywhere ? If you haven't bled them in a while you probably need to, or better yet, flush the system with new fluid (that makes a huge difference in the feel of the brakes).

There is also a valve (brake differential valve) usually right up under the master cylinder that detects different pressures in the system (such as a leak) and triggers an electrical switch that usually lights up the emegency brake light. I'm pretty sure our cars have this (can't go look right now) and if it's not an electrical gremlin then you need to look your brakes over very well !

Here's a website that explains it in general, pedal down to the differential valve: http://auto.howstuffworks.com/master-brake2.htm
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
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Mill Creek, WA
Jul 30, 2004
#9
  • Jul 30, 2004
  • #9
ss93cobra said:
89MUSTANGGX-So, when it happened to my wife's car and I changed the rear shoes and the light went off, it was just coincidence? Just because it doesn't make sense doesn't mean its not possible.
Click to expand...

Go follow the wires all around the car and you will see there are no wires connected to your brakes. It is possible that as the brakes get worn - front or rear -- that the fluid level in the master cylinder goes down and could cause the light to go on -- but it's not due to the brakes, it's due to lack of fluid.

BlackGT89 said:
There is also a valve (brake differential valve) usually right up under the master cylinder that detects different pressures in the system (such as a leak) and triggers an electrical switch that usually lights up the emegency brake light. I'm pretty sure our cars have this (can't go look right now) and if it's not an electrical gremlin then you need to look your brakes over very well !
Click to expand...

I'm not aware of any valves that are connected to the switch in the cylinder there. The switch is just your basic low-level switch AFAIK. I've never seen this come on with any of the brake work/problems I've had.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jul 30, 2004
#10
  • Jul 30, 2004
  • #10
89MustangGX said:
I'm not aware of any valves that are connected to the switch in the cylinder there. The switch is just your basic low-level switch AFAIK. I've never seen this come on with any of the brake work/problems I've had.
Click to expand...
agreed - i read that earlier and forgot to reply. some newer cars have all sorts of nice new stuff, but our antiquated stangs dont.
 

BlackGT89

Member
Dec 16, 2002
774
8
18
Huntsville, AL
Aug 2, 2004
#11
  • Aug 2, 2004
  • #11
89MustangGX said:
I'm not aware of any valves that are connected to the switch in the cylinder there. The switch is just your basic low-level switch AFAIK. I've never seen this come on with any of the brake work/problems I've had.
Click to expand...

I checked my manual and only the pre-87 Mustangs had this differential valve with the electrical switch. Guess I was thinking of my old 67, I know it had it because it was the dickens to get centered again and make the brake light go off. The 87 and up only has a level sensor under the reservoir.

Link on the valve:

http://www.cougarclub.org/atsotc/brake_valves.shtml
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Aug 2, 2004
#12
  • Aug 2, 2004
  • #12
Good info, thanks.
 

extozy

New Member
Sep 7, 2003
93
0
0
Longview, TX
Aug 7, 2004
#13
  • Aug 7, 2004
  • #13
i haven't done any of the things you guys told me, but i guess i should also tell you my mustang has had a 5 lug conversion, and all disc brakes, the right rear brake doesn't even seem to work at all, sometimes the light like blinks on and off when i'm driving, like its touching something... My E-Brake won't even stop my car from rolling... any more ideas?
 

extozy

New Member
Sep 7, 2003
93
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0
Longview, TX
Aug 7, 2004
#14
  • Aug 7, 2004
  • #14
and like i was saying, whats the deal with the brights not working when i pull them back, and the light going off when i push it forward? where would the ground even be?
 

dvs bullet

New Member
Feb 20, 2004
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Ontario, Canada
Aug 7, 2004
#15
  • Aug 7, 2004
  • #15
ss93cobra said:
89MUSTANGGX-So, when it happened to my wife's car and I changed the rear shoes and the light went off, it was just coincidence? Just because it doesn't make sense doesn't mean its not possible.
Click to expand...


When you put new brakes on a vehicle there is more pad surface so you have to push the piston back, this pushes fliud back into the master cylinder filling it up, you had low brake fluid.
 

extozy

New Member
Sep 7, 2003
93
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0
Longview, TX
Aug 12, 2004
#16
  • Aug 12, 2004
  • #16
bump
 
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