I have been installing a new wiring harness in my truck. I want to replace everything that I can. I am wondering if the neutral safety switch and backup light switches are one unit or separate. I finally got a wiring diagram and want to try and hook up the dual brake warning light/switch. I am not sure if the switch is bad or not, it was one of the hack jobs from previous owners. I have found several places with the neutral and backup switches, which the prices are not very consitant. I have not been able to locate the brake warning switch. Thanks in advance!

 

Most of the switches I have seen are combination back-up and neutral safety. Look on the side of your tranny where the shifter lever comes out. If there is a plastic piece behind the lever with four wires coming out, then it is a combo switch.

Your brake switch is made into the proportioning valve. It's a metal block with a bunch of brake lines running to it. There will be a stud on top where the wires hooks for the light.

 

I'm pretty sure my neutral saftey is at the bottom of the steering column inside the cab. There are a bunch of disconnected wires coming out of it. I guess I need to look at it with the diagram near by. There are not any wires on the tranny at all. So I guess that means I have the separate setup??? Thanks for the brake warning switch info!

 

For many years Ford used red/lightblue for the neutral start circuit. And two of these color wires would be coming out of the neutral start switch, but your truck is older and I don't have a diagram for it. I think it would be safe to say if you have more than two wires coming out of the switch on the column, that the back-up lights are probably in there too.

 

I just pulled the switch off. According to my diagram the backup light switch has two wires, both black/red stripe. I have both in the switch. My diagram does not show the neutral saftey switch wiring. But I do have 2 more (total of 4) coming out of the switch. The other two are the red/blue stripe you are talking about for the neutral saftey. BTW, one of the backup light wires was cutoff for some reason! So I think that wraps this one up. Thanks Dave!

Bryan

 

Dave,

Larry at Blue Oval Truck Parts just replied with a part # for the brake switch. It's C8AZ 2BZ64 A. He says that it attaches TO the proportioning valve and it $19.95. Does that sound right to you? I am going to check it out some more. Do you know any sites where I could identify the Ford part by it's part #?

 

"Do you know any sites where I could identify the Ford part by it's part #?"

Nope.

And there are two kinds of brake switches I know of. I am not sure of your year truck, but some of the older trucks did not have a brake switch on the brake pedal arm, but had a pressure switch screwed into the brake system to activate the brake lights. I just wanted to mention that so you can make sure someone doesn't get mixed up about which switch you want.

The one you mentioned in your first post, warns of a system failure, and the wire goes to the proportioning valve. I wasn't sure if it was part of the valve or it could actually be replaced.

How the brake warning switch works is, you have your front and back brake systems both going to the valve. The only thing that seperates the two brake systems is a metal plunger in the middle of the valve. So long as you have pressure on both systems, the metal plunger stays in the middle. If you have a brake line bust or something, the pressure from the system that is still working will push the plunger over, and ground the wire out to turn the light on.

 

I didn't think about suppliers thinking that I was talking about the stoplight switch. Yes, my stoplight switch is located on the brake pedal arm. I have been able to locate that all the major parts stores in my area. It has already been replaced.

I plan on looking at the proportioning valve much closer this weekend. From what I have seen, the part from Blue Oval should be the switch that can be removed from the valve at $19.95. I spoke to Larry at Blue Oval on the phone, and clearly mentioned the switch for the little red light on the dash. He seemed to know exactly what I was talking about. Blue Oval does list the stoplight switch too.

I have not been able to find a replacement valve for my '68. I did see valves for 73 and up at $85. I would have to place a special order to get the brake system warning light switch. I figured that when Larry gave me the original Ford part # instead of his company's usual #. Of course, I'll let you know what I find out as I go.

As far as the neutral safety and reverse light switch, Autozone is the only one that carries it in normal stock here. The other parts stores have to special order it and some of them list it at almost twice the price. I was able to compare Autozone's today in the store and its a match. That one is $27.99.

Thanks again Dave!

Bryan