Proportional valve wire

[conoco]

Can anyone tell me what this wire is for and where it connects too. I checked and it has power to it, just dont know where it goes. Both my manuals I cant seem to find the wire in there either

[RustyPile]

Originally Posted by conoco

Can anyone tell me what this wire is for and where it connects too. I checked and it has power to it, just dont know where it goes. Both my manuals I cant seem to find the wire in there either

In the wiring diagram, it's labeled "brake warning light switch".. The switch is mounted on the brake proportioning valve located on a bracket mounted to the brake master cylinder. In the event of a hydraulic failure in the braking system, the brake warning light switch grounds that tan wire and turns on the brake warning light.

[conoco]

[QUOTE=RustyPile;8692756]In the wiring diagram, it's labeled "brake warning light switch".. The switch is mounted on the brake proportioning valve located on a bracket mounted to the brake master cylinder. In the event of a hydraulic failure in the braking system, the brake warning light switch grounds that tan wire and turns on the brake warning light.[/QUOTE

That makes sense, thank you. Does this plug into behind the dash then? It has the connector on it already and obviously plugs in somewhere, maybe the wire was taken put by the PO, It is definitely something I would want hooked up so if something was wrong I would know. Thanks again.

[RustyPile]

Originally Posted by conoco

That makes sense, thank you. Does this plug into behind the dash then? It has the connector on it already and obviously plugs in somewhere, maybe the wire was taken put by the PO, It is definitely something I would want hooked up so if something was wrong I would know. Thanks again.

It's all right there in the diagram... The color of the wire is tan. It's a 20 ga. wire and goes through the bulkhead connector to the ignition switch and then to the connector for the instrument cluster. It's tan all the way to the cluster connector.. Do not confuse it with the 18 ga. wire coming from the dimmer switch, and going to the headlights..

You say it has power??. That means the bulb is good and the circuit is basically complete and working. To test the brake warning light circuit, simply disconnect the wire from the proportioning valve and ground the wire.. With the ignition key in the "ON" position, the warning light on the dash will come on.. If it does, then you have a working circuit -- Stop fiddling with it..

If that tan wire truly has power on it and the bulb doesn't light up when you ground that wire, you don't have the wire connected to a good ground.. Keep trying..

[rpmerf]

http://outintheshop.com/faq/wiring/w...s/image002.jpg

http://outintheshop.com/faq/wiring/w...s/image003.jpg

I believe the bulb also lights up when you turn the ignition to start.

[conoco]

Originally Posted by RustyPile

It's all right there in the diagram... The color of the wire is tan. It's a 20 ga. wire and goes through the bulkhead connector to the ignition switch and then to the connector for the instrument cluster. It's tan all the way to the cluster connector.. Do not confuse it with the 18 ga. wire coming from the dimmer switch, and going to the headlights..

You say it has power??. That means the bulb is good and the circuit is basically complete and working. To test the brake warning light circuit, simply disconnect the wire from the proportioning valve and ground the wire.. With the ignition key in the "ON" position, the warning light on the dash will come on.. If it does, then you have a working circuit -- Stop fiddling with it..

If that tan wire truly has power on it and the bulb doesn't light up when you ground that wire, you don't have the wire connected to a good ground.. Keep trying..

Thank you very much. I will test it out. I just replaced the circuit board and all the bulbs and everything looked good power wise. I also tested that connector in the photo above once everything was hooked back up. I just didnt know where that connector in my hand connected to. I will look around and trace it. Thank you for taking the time to explain it to me.

[RustyPile]

Originally Posted by conoco

Thank you very much. I will test it out. I just replaced the circuit board and all the bulbs and everything looked good power wise. I also tested that connector in the photo above once everything was hooked back up. I just didn't know where that connector in my hand connected to. I will look around and trace it. Thank you for taking the time to explain it to me.

That's fiddling with it.. IF it passes the test I described, leave it alone.. Fiddling around like that when it's not called for is what's causing some of your problems.. BTW, did you get the dash lights working properly???

[RustyPile]

Originally Posted by rpmerf

http://outintheshop.com/faq/wiring/w...s/image002.jpg

http://outintheshop.com/faq/wiring/w...s/image003.jpg

I believe the bulb also lights up when you turn the ignition to start.

You are correct, but in this case, Conoco's truck wiring has several problems and I don't think it's safe at this time to attempt starting his engine.. When checking a particular circuit, it's best to err on the side of safety and keep as many circuits as possible isolated from the "equation".. Thanks for your input..

[conoco]

I did get it all FIXED!! YOU SHOULD HAVE SEEN MY FACE!! everything works now including the fiber optic cable !! It had to have been 1 of 4 things or combinations of them all. I replaced the headlight switch, I replaced all 4 of my headlights, I replaced the circuit board and I cleaned all the grounds that I know of for the truck. A couple of them were like cement. I also started reading every damn thing I could on this forum related to the topic and saw that some recommend adding an additional ground wire from the dash to somewhere on the fire wall, which I did. I also added a ground from the temp gauge bottom post to the back metal piece of the cluster and now my temp gauge works!! I was getting so frustrated, I appreciate everyone's help.

My brake light comes on temporarily when I turn the key to start it, but that wire in the pic I posted isnt connected to anything and I just didnt know where it went to. My other truck manual came in today and will start reading up on it.

On a side note so I dont have to start another post, can you guys confirm that there should be an o ring inside this in the picture? My speedo cable is leaking from the transfer case. I found where I can get that entire piece as I guess they are harder to get now. I just thought I read that it was leaking by because the o ring inside where the cable attaches to wears out.

Thanks again for all the help and suggestions, this has been by far the best tool.

[RustyPile]

Back in the time when I worked on these trucks, 4X4 wasn't a popular option so I don't have a bunch of experience with 4X4 powertrains.. That black "line" inside that fitting is probably the O ring.. Use a dental pick or other suitable tool and remove it.. Clean the groove really good. Coat the new O ring with a bit of grease and work it into place.. There may also be an O ring on the outside fitting under the "head".. This would seal the fitting against the case.

[RustyPile]

That connector in the picture in your first post... What color is the wire?? I'm just guessing here but that connector could be where the FWD indicator light harness plugs in.. Does that light work on your truck?? There's a notation on my wiring diagram that says there is a connector/pigtail coming off the alternator feed wire going to the ignition switch.. According to my diagram, that connector should be in the vicinity of the brake booster or DS hood hinge.. Diagram doesn't say what color the pigtail is, but my guess would be red..

[Andy4639]

Conoco,
that connector in your hand is not the right connector for the brake light switch. The brake light switch connector is round. There should be a single wire hooked to the proportioning valve between the two lines either top are bottom. It's the rubber boot in the second picture. The wire is running under the master cylinder around proportioning valve.

I don't know what that one is for sure but it's not the brake light switch.

Yes the brake light should come on as you crank the truck. It's a check that the bulb is working.

[RustyPile]

Originally Posted by Andy4639

Conoco,
that connector in your hand is not the right connector for the brake light switch. The brake light switch connector is round. There should be a single wire hooked to the proportioning valve between the two lines either top are bottom. It's the rubber boot in the second picture. The wire is running under the master cylinder around proportioning valve.

I don't know what that one is for sure but it's not the brake light switch.

Yes the brake light should come on as you crank the truck. It's a check that the bulb is working.

Andy, I never said it was.. Look closely at the pictures. Conoco is holding a wire in both pictures. Just for the record, In my detailed description of the brake warning light circuit, I was referencing the second picture. The one showing the proportioning valve.. If Conoco wasn't concerned about that wire on the valve, why did he post a picture of it?????

When I was describing the FWD light circuit, I was referencing the plug in the first picture. I also stated I was guessing as to it's actual purpose..

I stand by my original statements..

In all honesty, Conoco and you were/are possibly confused by my descriptions.. I hope this post clears up the confusion...

[Andy4639]

Originally Posted by RustyPile

Andy, I never said it was.. Look closely at the pictures. Conoco is holding a wire in both pictures. Just for the record, In my detailed description of the brake warning light circuit, I was referencing the second picture. The one showing the proportioning valve.. If Conoco wasn't concerned about that wire on the valve, why did he post a picture of it?????

When I was describing the FWD light circuit, I was referencing the plug in the first picture. I also stated I was guessing as to it's actual purpose..

I stand by my original statements..

In all honesty, Conoco and you were/are possibly confused by my descriptions.. I hope this post clears up the confusion...

I never mentioned your comment's, I was going by his pictures. The first picture isn't the right connector and I stated the other one was. I have no idea what the first connection is except maybe for the temp sensor but he didn't say anything about it not working. It's not the right color wire though so who knows what it is. It could be some old air pump emissions stuff also.