Disconnecting ABS Brake system

[1990JEEPXJ]

yes, you have not fully disabled it.

so locking up my brakes isnt an indicator that the ABS has been disabled?

You continue to tell people to do this even though it's widely known to be unreliable and dangerous, and you admit you don't fully understand what you have done to it. Kindly stop. This is like telling people it's fine to check if a revolver is empty by pointing it at your foot and pulling the trigger because hey, you did it and it didn't shoot you... that time.

It is a fairly simple mod to do it right and end up with safe brakes, and the parts are cheap.

Cliff notes: SPOBI

i have never told people to do it. i said it can be done and i am an example. stop putting words in my mouth. i concede to the fact that it is an unreliable system, but in my case it has not poven to be so. youre essentially saying that anyone that uses anything that others say is unreliable that the most extreme consequences will be suffered, which is a little far-fetched. and as i have said MANY times this is not a permanent solution and i WILL change it. im done arguing about this. !!!1


FYI there are 2 fuses under the dash for the ABS. one labeled ABS IGN and another labeled ABS BATT.

 

[casm]

It's an 01. Had ABS, now don't.

You're fine. More:

If the D44 and HP30 had it I would have connected it.

Same here (though I'm still running the LP30). Continued:

I really can't feel any difference.

There are circumstances where you will - notably, short panic stops, especially in the wet - but a rear disc conversion on your D44 will give you the same (if not better) braking overall IMHO. Note that I say this as someone who intends to add ABS back to his disc-brake D44 one of these days, but if you can properly pump the pedal, you'll be OK in the meantime.

I suppose the tires will now lock up and not pulse cycle. In states with annual inspections this might be a problem.

Given how crappy the XJ's rear drums can be after a couple of years from new, you might well be surprised.

 

[1096xj]

Let me see if I can muddy the water any better. The abs part of the system is not the problem. It works well and even when it does not the only thing you have is an abs system that acts like an old style non abs. The problem is that they used the high pressure system to give the power assist to the system. That is the pump you hear running. The pump should not run all the time. The accumulator or pressure reservoir stores pressure and the pump runs to rebuild it. As long as it runs and you don't pull the fuse to the pump you will have power brakes. The pump itself and the actuator are the covered parts. I have the system on my 90 xj Limited. The pump has gone out and you do not instantly loose brakes. You loose the power assist and it takes increasingly harder pedal pressure to brake as the high pressure is used up. Even after it is gone you still have brakes. It just takes a lot more foot pressure on the pedal to stop. Depending on the situation, if you are not aware of this you may not react in time to stop in time. It was not a huge deal for me as I had an old ford truck with drum brakes all around and no power. I hope this makes sense. You can disable the abs with no worries. Its the pump that is the problem. One more note. This system uses a special master cylinder that so far I have only found at the dealership. They only have remanufactured ones and they are in the neighborhood of $600.00.

 

[lawsoncl]

so locking up my brakes isnt an indicator that the ABS has been disabled?... FYI there are 2 fuses under the dash for the ABS. one labeled ABS IGN and another labeled ABS BATT.

The pump is still powered and maintaining pressure in your accumulator, hence you still have brakes. It sounds like the fuse(s) you pulled have only disabled the ABS electronics portion of the system (which wasn't the common failure point). So its semantics really. Yes you've disabled the ABS functionality, but you're still vulnerable to the high failure rate of the Bendix pump which can leave you without brakes. I don't see your solution as a big improvement aside from not having to deal with disadvantages of ABS while off-road.

For an older Renix with the ABS, I would recommend ripping it all out, and installing a 96 double-booster and master cylinder. Far better braking and less breaking.

 

[lawsoncl]

FYI there are 2 fuses under the dash for the ABS. one labeled ABS IGN and another labeled ABS BATT.

Curious. Looking at the wiring diagram, the pump is powered through the ABS-IGN fuse.

 

[1990JEEPXJ]

The pump is still powered and maintaining pressure in your accumulator, hence you still have brakes. It sounds like the fuse(s) you pulled have only disabled the ABS electronics portion of the system (which wasn't the common failure point). So its semantics really. Yes you've disabled the ABS functionality, but you're still vulnerable to the high failure rate of the Bendix pump which can leave you without brakes. I don't see your solution as a big improvement aside from not having to deal with disadvantages of ABS while off-road.

For an older Renix with the ABS, I would recommend ripping it all out, and installing a 96 double-booster and master cylinder. Far better braking and less breaking.

i agree with you on all of that. its not an improvement aside from the fact that the ABS is no longer functioning. i am planning on a WJ booster swap as well.

Curious. Looking at the wiring diagram, the pump is powered through the ABS-IGN fuse.

thats what i figured out because i have the ABS-BATT fuse pulled. the rest are all there.

 

[rusco7]

Does anyone have a picture on what fuses and or relays to un-plug. I have a 2000 with an 8.8 rear and D30 HP swap up front. Thanks!

 

[stockli]

We had to pull the whole system out of my friends 98 because with just the fuse pulled it made the breaks act funny. The rears made all kinds of noise and one tire would lock up.

Pulled the whole mess and now its just fine.

 

[solomon7]

On my 96 USFS XJ I pulled the ABS relay from the PDC under the hood and a 2 amp fuse (#7 iirc) from the kicker panel.
The relay disabled the abs abd the fuse killed the warning light.
The XJ's computer has no idea it ever had ABS.
Aside from some space being taken up in the bay with useless abs stuff, all is well and works as it should. No codes or anything.

 

[tom11919]

In case anybody wants to keep their ABS functional with a Ford 8.8:

http://naxja.org/forum/showthread.php?t=1077938

Initial results are promising. I tried locking up the brakes on grass and got the normal brrrr-brrrr-brrrrr pedal buzzing ABS stopping reaction. With an 8.8.