Troubleshooting question...

Thread Tools
 
Search this Thread
 
Old Sep 1, 2019 | 07:41 AM
  #1  
72455's Avatar
Thread Starter
1972 U code Supreme
 
Joined: Jul 2018
Posts: 4,097
From: Chesapeake, VA
Troubleshooting question...

Was going take my '72 Supreme to work today, and when I turned the corner out of the court, the dash light came on for the brakes..uh oh. Made my way back to the house, and my brakes are working fine. My research here on CO is pointing me to the parking brake release switch. Question is, if I disconnect the switch and the light goes out, then it's the switch, right?
Old Sep 1, 2019 | 09:42 AM
  #2  
jaunty75's Avatar
Registered User
 
Joined: Jun 2009
Posts: 15,192
From: southeastern Michigan
You're kidding, right?
Old Sep 1, 2019 | 10:30 AM
  #3  
72455's Avatar
Thread Starter
1972 U code Supreme
 
Joined: Jul 2018
Posts: 4,097
From: Chesapeake, VA
Originally Posted by jaunty75
You're kidding, right?
Um..no...why?
Old Sep 1, 2019 | 10:37 AM
  #4  
oldcutlass's Avatar
Administrator
 
Joined: Oct 2009
Posts: 42,496
From: Poteau, Ok
First check the master cylinder and see if its full in both chambers. If the light goes out when you unplug the switch at the Ebrake then its not returning all the way or the switch is out of alignment or faulty.
Old Sep 1, 2019 | 10:44 AM
  #5  
jaunty75's Avatar
Registered User
 
Joined: Jun 2009
Posts: 15,192
From: southeastern Michigan
If you disconnect the switch, you have broken the circuit, and the light will go out no matter what. What you need to do is test the switch itself. It's just a plunger-type switch like the kind that makes the brake lights go on when you step on the pedal. If the parking brake is released, that switch should not be pushed in, and the light should not be on. If it IS on, the first thing to check is to make sure the parking brake is fully released and that the plunger is actually fully out and not stuck in the pushed-in position. If the plunger is fully out and the light is still on, then you need to isolate the switch and put an Ohmmeter across the two leads. With the plunger pushed in, there should be zero resistance. With it out, there should be an open circuit (infinite resistance). If if doesn't pass this test, then the switch needs to be either repaired or replaced.
Old Sep 1, 2019 | 01:31 PM
  #6  
72455's Avatar
Thread Starter
1972 U code Supreme
 
Joined: Jul 2018
Posts: 4,097
From: Chesapeake, VA
So if it was fine yesterday when I drove it, and it was fine when I started it up this morning, is it a common occurrence for the switch to act up all of a sudden?
Old Sep 1, 2019 | 01:39 PM
  #7  
oldcutlass's Avatar
Administrator
 
Joined: Oct 2009
Posts: 42,496
From: Poteau, Ok
Its a 47 year old car, nothing is normal.
Old Sep 1, 2019 | 05:21 PM
  #8  
72455's Avatar
Thread Starter
1972 U code Supreme
 
Joined: Jul 2018
Posts: 4,097
From: Chesapeake, VA
Originally Posted by oldcutlass
Its a 47 year old car, nothing is normal.
LOL...somehow I knew that would be the response 😀
Old Sep 1, 2019 | 07:31 PM
  #9  
72455's Avatar
Thread Starter
1972 U code Supreme
 
Joined: Jul 2018
Posts: 4,097
From: Chesapeake, VA
Checked it out...fluid level was good, didn't have any leaks. Gave the parking brake pedal a slight tug and hit the key. Light was out, so I'm guessing it was the switch but I'll keep an eye on it. Thanks to all who helped.
Old Sep 1, 2019 | 07:38 PM
  #10  
oldcutlass's Avatar
Administrator
 
Joined: Oct 2009
Posts: 42,496
From: Poteau, Ok
Lubricate the pivot points and the cable.
Old Sep 1, 2019 | 07:43 PM
  #11  
72455's Avatar
Thread Starter
1972 U code Supreme
 
Joined: Jul 2018
Posts: 4,097
From: Chesapeake, VA
Originally Posted by oldcutlass
Lubricate the pivot points and the cable.
The pivot points for the pedal?
Old Sep 1, 2019 | 08:15 PM
  #12  
oldcutlass's Avatar
Administrator
 
Joined: Oct 2009
Posts: 42,496
From: Poteau, Ok
Originally Posted by 72455
The pivot points for the pedal?
Yes
Old Sep 2, 2019 | 06:32 AM
  #13  
TripDeuces's Avatar
Registered User
 
Joined: Jun 2010
Posts: 3,613
From: Rogues Island, USA
Is it nothing more then the emergency brake pedal pushing on its switch? Grab the e-brake pad and pull it toward you while holding the brake release.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
dave marki
General Discussion
4
Sep 1, 2015 10:43 AM
66olds98convertible
Electrical
6
Sep 27, 2014 06:48 PM
FirstClass 383
General Discussion
6
Aug 6, 2013 06:17 PM
starfire
Ninety-Eight
0
Mar 11, 2013 02:51 PM
Oldsmobilliam
Electrical
11
Dec 1, 2009 05:56 AM




All times are GMT -7. The time now is 10:50 AM.