Brake pedal switch - Brake controler

[Dave Mac]

I'm trying to figure out what is the correct wire to hook my brake controler to my brake pedal switch. I have a 1993 Jeep Wrangler. The controler says to hook one of the wires to the cold side of the brake pedal switch. If anyone has done this on a Jeep Wrangler let me know. other wise I guess I need to figure out how to test the wires to know which one is sending power AFTER the pedal is depressed.
Dave

[Brian B-P]

As others have pointed out, the brake control manufacturers are pretty good about knowing which wire is which in various tow vehicles - I'd call and ask if I needed help.

What I did for my Toyota was just to connect the negative probe of a voltmeter to some thing "grounded" (a body bolt), and the use the positive probe to test each terminal of the switch on the brake pedal. The pedal just has to move enough to trip the switch, and that takes nearly no force, so I found it easy to just move it with my hand. The terminal which is off (no volts) with the pedal up and on (about 12V) when the pedal is pushed down is the one you want.

A test light would work as well: the one you want is no light with pedal up, lit with pedal down.

There was one terminal of the four on my Toyota which behaved the right way. If there are two - I dunno. There shouldn't be two...

[Dave Mac]

As others have pointed out, the brake control manufacturers are pretty good about knowing which wire is which in various tow vehicles - I'd call and ask if I needed help.

What I did for my Toyota was just to connect the negative probe of a voltmeter to some thing "grounded" (a body bolt), and the use the positive probe to test each terminal of the switch on the brake pedal. The pedal just has to move enough to trip the switch, and that takes nearly no force, so I found it easy to just move it with my hand. The terminal which is off (no volts) with the pedal up and on (about 12V) when the pedal is pushed down is the one you want.

A test light would work as well: the one you want is no light with pedal up, lit with pedal down.

There was one terminal of the four on my Toyota which behaved the right way. If there are two - I dunno. There shouldn't be two...

HEY! you made a bulb light up in the old brain.
I could take a 12 volt dummy tester And unhook the wire connector that connects this pedal switch. then I would have good access to the conductors on the connector. Ground one side of the tester and start probing wires as you said looking for the one that lights the tester ONLY when the pedal is depressed by hand enough to actuate the switch.
Dave

[Brian B-P]

Yes, Dave, except that if we're talking about the Jeep's original connector to the brake light switch, as soon as the connector is unplugged from the switch it won't matter anymore whether the pedal is pushed, because the switch isn't connected.

Terminal access with the connector plugged in can be a problem...

• With the connector off of the switch, you can test the harness side to see which terminal(s) is/are hot... it won't be that one (or those) you want to use.
• Still with the connector off, if there was only one hot wire in harness, then test with the meter set for resistance (ohms) between that terminal and each of the others. The combination which has infinite resistance normally, but switches to near zero when the pedal is pressed, is the likely candidate (not the hot terminal, the other one of the successful combination).
• With the connector plugged back in, attach the splice but don't connect the controller yet. Use the meter as voltmeter, or the test light, to confirm that this wire goes from dead to live when the pedal is pushed.

I did some connector-off probing on my Toyota, too, since I wanted to be sure of the arrangement.

[Pete Dumbleton]

Umm, don't you guys have the wiring diagrams for your vehicles?

Whenever I'd buy a Chrysler product, the first accessory I'd get is the service manual. When I had a Saturn, the manual was hideously expensive, so I got the Haynes manual. For my Ford Ranger, I got the complete service dept CD on EBay for less than $10.

Lacking a wiring diagram, I'd use the 1-800 number and call Tekonsha (even if you don't have a Tekonsha) and ask the tech where the cold wire is.

Whilst perusing the Tekonsha site the other day, I ran across a table of wires, but it didn't have the Wrangler in it. It's a good reference to have, BTW, with brakes, bearings, couplers, etc. in it although it's a 5M download.

http://www.tekonsha.com/Brakes/PDF/C...-Cat-2006f.pdf

[Brian B-P]

Umm, don't you guys have the wiring diagrams for your vehicles?

No. When I bought my first new car (a Toyota), I ordered the service manual the day I picked up the car. It was a valuable asset in the maintenance of the vehicle.

Currently, Toyota sells the manuals for a substantial price, and the intelligent option is to buy on-line access instead. If you want, you can download the whole manual in sections, to have a local copy. Unfortunately, the on-line access is only available to U.S. residents... Toyota Canada apparently does not want me to have ready access to technical information. My current scheme is to bug the dealership for prints of specific sections every time I have a question; eventually, maybe they will have printed the whole thing at no cost to me and great expense to them, when I was quite willing to pay for it online...

This brings up a suggestion which may be actually useful. I have been able to get copies of specific sections of service manuals - including wiring diagrams - by nicely asking at Honda and Toyota dealerships. It may be worth a try at the Jeep store.

[Dave Mac]

Umm, don't you guys have the wiring diagrams for your vehicles?

Whenever I'd buy a Chrysler product, the first accessory I'd get is the service manual. When I had a Saturn, the manual was hideously expensive, so I got the Haynes manual. For my Ford Ranger, I got the complete service dept CD on EBay for less than $10.

Lacking a wiring diagram, I'd use the 1-800 number and call Tekonsha (even if you don't have a Tekonsha) and ask the tech where the cold wire is.

Whilst perusing the Tekonsha site the other day, I ran across a table of wires, but it didn't have the Wrangler in it. It's a good reference to have, BTW, with brakes, bearings, couplers, etc. in it although it's a 5M download.

http://www.tekonsha.com/Brakes/PDF/C...-Cat-2006f.pdf

I have a book on the Jeep but the wiring on the switch is pretty hard to figure out even with the diagram.

[Dave Mac]

looks kind of like this.

[Brian B-P]

I think the problem is that the given section of the diagram doesn't show the brake pedal switch at all.. the "park brake switch" is on the parking brake (not the regular brake pedal), and the "brake warning switch" is probably the failure indicator (which trips when the pressures in the two brake circuits don't match, which is why it has that either-way-on appearance).

Dave, do you have the section which includes the actual brake pedal switch?

[Pete Dumbleton]

What Brian said...

[R Jope]

I have a book on the Jeep but the wiring on the switch is pretty hard to figure out even with the diagram.

It would take longer to look it up in a book than to test it out.

The switch should have only two terminals. You can't get much simpler than that. One will be hot all the time, even with the ignition off. Disconnect the switch and using a test light or voltmeter between the connector and a ground (screw or bolt under the dash), find the terminal that has power. The dead terminal in the connector is the cold side. In real Jeeps the hot wire was usually pink. Not sure about the mopar Jeeps.

[Pete Dumbleton]

In real Jeeps the hot wire was usually pink. Not sure about the mopar Jeeps.

May we presume you are talking about the French (Renault) Jeeps, before Mopar took control?

[Dave Mac]

Well I got it done! There weree alot of wires there to chose from because of some other splices that were made for something I don't know what. Any way I got the correct wire figured out and made a few connections today. Installed the 20amp auto circuit breaker. I have found a place to conect the white to ground. Tomorrow I will be running the blue wire from my trailer conection and another auxilary power wire down under the frame to the firewall and inside the jeep. These are the last 2 connections I need to make for the brake controler and with luck I will be hooking up the Burro to the Jeep for the first time and testing the brakes out.
I am going to air up the trailer tires to max or very near max pressure. then I need to figure out what to air the jeep tires to. These are BFG AT TKO 30x9.5s that I upgraded to some years ago. The tires on now are pretty new on both jeep and trailer.
I'm almost there. Then I can tow it to my buddies house where we can make new storage hatch covers.
Dave

[R Jope]

then I need to figure out what to air the jeep tires to. These are BFG AT TKO 30x9.5s that I upgraded to some years ago. The tires on now are pretty new on both jeep and trailer.

Call the dealer and ask what the pressures are supposed to be for a 2000 TJ with the 30" package. Very good starting point as the weights are close.

May we presume you are talking about the French (Renault) Jeeps, before Mopar took control?

At least Renault didn't kill off one of the best pickups ever made (J-series). When Mopar took over they completely alienated their previous owner base and killed parts availability. Couldn't even get a taillight lens for a 6 year old vehicle. But that's a discussion for another forum.