wiring for parking brake switch

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duanecr

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I am trying to get my parking brake switch to work, but I'm starting to run up against a wall. I have traced the wire from the switch on the parking brake to the brown plug at the relay panel over the glove box. It is circuit 162, Light Green-Red Dash wire. I am missing the other side of the plug and don't know where the connection is supposed to go next. I have seen several pictures on the internet and this forum (including the PDF with multiple pictures and diagrams) but none clearly show the other half of the connector and where the cables go. The 73 Mustang wiring diagram shows the connection going straight from the parking brake warning lamp (in the dash) to this connector, but that does not line up with what I'm seeing. Does anyone have a clear picture or explanation of where the other (female) side of this connector goes? A picture of that harness that this goes in would be ideal.
 

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midlife

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That's the infamous convenience harness that mates to that plug. If you don't have that harness, you won't be able to hook up your parking brake switch per factory.
 

duanecr

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That's the infamous convenience harness that mates to that plug. If you don't have that harness, you won't be able to hook up your parking brake switch per factory.
Thanks! I found out late last night that my car doesn't have that convenience package. I had the misunderstanding that the "Brakes" light in the dash was for the parking brake. Not so. That is only for a failure of the master cylinder. So, now I get to argue with VA state inspectors that my car doesn't have a parking brake light. I may still hook it up, but given other priorities, I just want to get the car running and back on the road.
 
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Hello and welcome from SW Ontario, Canada.
Parking brake light and switch is the subject of a thread I started a few months ago because my car, being a very basic 71 Mach 1, did not have that little luxury item. Not having that light, has caused this old man to forget to release the p/brake ( and NO it's NOT an emergency brake!!), on more than one occasion.
I think you might find that there is not a switch attached to the p/brake mechanism. This is almost impossible to see without removing it, or doing contortions to take pictures.
In my case, the hydraulic brake system is split so the brake failure light is not connected. It was my plan to add a small switch (which didn't work) to the p/brake pedal and jump wire it into the failure circuit. I found I need the correct switch, which is available from NPD etc. but not cheap.
If in your case the brake failure (as I call it) light is not working, it could be a blown bulb or the switch within the proportioning valve is not working.
Please go to "Introductions" and tell us more about your car and where you're from. (I don't do the F/B thing!)
 
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duanecr

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Hello and welcome from SW Ontario, Canada.
Parking brake light and switch is the subject of a thread I started a few months ago because my car, being a very basic 71 Mach 1, did not have that little luxury item. Not having that light, has caused this old man to forget to release the p/brake ( and NO it's NOT an emergency brake!!), on more than one occasion.
I think you might find that there is not a switch attached to the p/brake mechanism. This is almost impossible to see without removing it, or doing contortions to take pictures.
In my case, the hydraulic brake system is split so the brake failure light is not connected. It was my plan to add a small switch (which didn't work) to the p/brake pedal and jump wire it into the failure circuit. I found I need the correct switch, which is available from NPD etc. but not cheap.
If in your case the brake failure (as I call it) light is not working, it could be a blown bulb or the switch within the proportioning valve is not working.
Please go to "Introductions" and tell us more about your car and where you're from. (I don't do the F/B thing!)
Thanks. I did see your post and discussion on the topic. The Brakes light is fine. I was just confused on the purpose of that light. Now knowing that there is another light, which mine does not have, for the parking brake light, I will have to decide whether I want to install one. I did buy the OEM parking brake switch from eBay for $15. I see how to mount it and may install it just to have it there later if I do install a light. I dropped the fresh air vent to get to it. For now, I'm just going to leave it alone and work on the next thing on my list. :)
 
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Thanks. I did see your post and discussion on the topic. The Brakes light is fine. I was just confused on the purpose of that light. Now knowing that there is another light, which mine does not have, for the parking brake light, I will have to decide whether I want to install one. I did buy the OEM parking brake switch from eBay for $15. I see how to mount it and may install it just to have it there later if I do install a light. I dropped the fresh air vent to get to it. For now, I'm just going to leave it alone and work on the next thing on my list. :)
Ok that's good to know. So, you're at the same place I am then, I would definitely like to add that light, because I've forgotten I've engaged the p/brake POS way too many times, but fortunately without damage.
With a 4 speed, if only the US manufactures (and I do mean all of them) had used a little intelligence and install HAND (parking)brakes as did ALL European manufacturers, I wouldn't have this problem and also have the ability to do a fully controlled hill start. But I've said that many times, sorry if it's getting old.
 

Aus73Mach1

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Q code. 351-4V
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I put mine as shown. Already a hole in that spot. RHD doesn't matter, put a hole where you can see it. Power then supplied to the light, ign switched and then to the Park Brake Switch and ground the other side.

park brake light (2).jpg
 

ssiegel4

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Hello and welcome from SW Ontario, Canada.
Parking brake light and switch is the subject of a thread I started a few months ago because my car, being a very basic 71 Mach 1, did not have that little luxury item. Not having that light, has caused this old man to forget to release the p/brake ( and NO it's NOT an emergency brake!!), on more than one occasion.
I think you might find that there is not a switch attached to the p/brake mechanism. This is almost impossible to see without removing it, or doing contortions to take pictures.
In my case, the hydraulic brake system is split so the brake failure light is not connected. It was my plan to add a small switch (which didn't work) to the p/brake pedal and jump wire it into the failure circuit. I found I need the correct switch, which is available from NPD etc. but not cheap.
If in your case the brake failure (as I call it) light is not working, it could be a blown bulb or the switch within the proportioning valve is not working.
Please go to "Introductions" and tell us more about your car and where you're from. (I don't do the F/B thing!)
Is there a way to "test" if the Brake failure light is working without actually sabotaging your braking system?
 

Hemikiller

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Is there a way to "test" if the Brake failure light is working without actually sabotaging your braking system?

When turning the key to "Start", the brake warning lamp should illuminate along with the temperature light if you have the basic gauge setup. The alternator and oil pressure lights will illuminate in the "On" position.

You can also probe the connector at the dual brake warning switch. Find the one with 12V with the key in the "ON" position, and temporarily ground it. That should also illuminate the Brakes warning lamp.
 
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Is there a way to "test" if the Brake failure light is working without actually sabotaging your braking system?
Sorry, I'm not that knowledgeable on the electronic side of thing to answer that.
I take it you're talking about the main braking system, not just the parking brake the thread was referring to. I'm sure someone can give you the answer you need.
EDIT, well there you go. Hemikiller beat me too it.
 

bdennis

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Per above testing the brake fail light.. When the ignition is turned to start, the light should come on. then go out.
Assuming the light comes on, this shows that the wiring to the switch on the brake distribution block is working.
There are 2 wires that go to the switch on the brake distribution switch. One goes to the light on the dash and the other goes to the ignition. By turning on the ignition it grounds the wire in the ignition that then enables the light to illuminate.
The final step is to test the switch it self on the brake distribution block. I think, if you remove it from the block then it will sense no fluid and then if you ground it to the chassis it will make the light come on.. (I think...!) Im not 100% sure on this last step.

In terms of the emergency brake light, I too don't have the convenience group wiring. In looking at the wiring diagram, wire 162 (Light green with red dots) goes over to above the glove box and back. Assuming the emergency brake mechanism has the switch installed and goes to ground when engaged, then simply pick up the green with red dot wire, add a 12v lamp in series, drill a hole in the metal dash next to the head light switch, place the lamp in the hole with a relevant size gromet or enclosure and then connect the other end to a accessory power feed. I would use the feed for the radio. This way, the light will only come on when the car is on and if the emergency brake is on.
 
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Good info there (above).
What I was thinking of doing was to utilize the wire to the distribution block, white/purple I think, because on my car, I do not use that circuit. My brakes are separate front and rear, so the distribution block just acts as a junction for the front brake lines. If I use that wire, then the light in the dash, the old brake failure warning light, will act as the parking brake reminder. At least, that was my thinking.
 
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