Anyway around reprogramming an ABS unit

I wouldn't tap into the vehicle wiring but if you had a couple female spade terminals and some wire you could unplug the headlight and attach wires to it that way.

I'm not sure which one is the ground and the 2 powers on the headlight bulb without looking though.

 

Well I can do that. I’ll stop on buy some tomorrow. I know for sure what that is. I would do it now if I had some. I can run a test light to them to see what’s hot and what’s not. Turning on the headlights and try with headlights off. I’ll find the right ones before I tap into them.

I would say it would be a good idea to get some male ends also for the plug in / wiring harness. My opinion but could be wrong.

 

Ok. I’m sure you know that old saying curiosity killed the cat. Lol. Well it was getting the best of me. So I went out and pumped the brakes without the truck running. Had a good firm pedal. Started the truck and the pedal almost hit the floor. So is the brake booster good or bad ? I also pulled the master cylinder off it to check for brake fluid. I did find some around the inside ring where the cylinder slides in at. Now with that being said I got a coat hanger and checked the bottom of the booster. Coat hanger was dry as a bone. I just wonder if the brake fluid could have ran behind the master cylinder whenever I was putting fluid into the reservoir ? I wouldn’t think that would be possible but nothing is surprising me anymore with these brakes. So is the master good or bad ? This picture you can see is wet. I did touch it and in my opinion it was 100% brake fluid.

 

Looking at the wiring diagram it looks like one of the side pins is ground and the other is high beam.

I'm not sure a standard spade terminal would fit into the ABS connector without damaging the terminal.

I've never seen a bad booster cause a soft pedal, most of the time when they fail you have a hard pedal due to no assist from the booster.

Certainly not unheard of for master cylinders to leak into the booster (I see this quite often on GM trucks although the brakes typically still work fine the brake fluid just disappears).

I mean it could be leaking by internally as well, no way to tell for sure without being able to block off the lines and see if the pedal is still soft or replacing it.

 

I’ll definitely get some connectors tomorrow after work and make some up. Well at least I knocked 2 other things out of question for the brakes not working. Lol

 

Wired up to the headlights pictures

 

I assume the head light light up? Correct?

If so, the power and ground is not the problem.
The search continues.

 

Yes sir headlights are correct. I test them with a test light. Looking at the pigtail. Right side ground. Top center low beam which would be power. Left side is high beam which means power.

Honestly if I’m wrong please correct me.

 

Also I was using the passenger side pigtail. When I hooked them up in the abs wiring harness the drivers side headlight came on. I assume that is correct and that’s what it should have done. Been wrong way to many times in life and if I’m wrong this wouldn’t be a first.

 

For the head light.
Match the prong on the head light connector to the colors below.

Pink wire is high beam
Red/yellow is low beam.
White/black is ground.

So for clarification, the head light will light up using the ABS connection to power the head light?

 

This is easier.

 

Yes sir. When wired up to the ABS connection the lights come on. I greatly appreciate the color code. Thank you

 

Thank you

 

I just double checked myself with the wiring and it is spot on

 

Yeah, I’m not sure how you are “hooking up” the power to the head light.
It is good you got them to come on.

But you want to hook power to the head light bulb. Not the connector.
If you hooked power to the connector, you back feed to the other build. Not an ideal way to test things.
Better to just use the bulb next time.

 

Well with my luck I just messed something up then.

 

No, it’s fine.
You were still fused. And isolated by a relay.

Unfortunately, the power and ground is not your issue.
Not if they light up a head light………

 

Ok. Redone the test with headlight attached. Different numbers by a very little. Hopefully I got it right this time. Lol

 

We don’t really need the voltages.
But it didn’t hurt to include them.
The whole reason @Dm93 had you use a headlight was to confirm the wires could carry a load (current).
And now we know “they can”….

 

Hey buddy in all honesty I greatly appreciate the help and any help that you could give. I appreciate all of this.