BoraBora

Just picked up my JK from having Yukon 4.56 gears installed. Problem is now the ABS lights are on.

The guys at the shop seemed a little confused since the lines are fine, and said the lights should reset after "50 or so starts." Is there any validity behind this?

They did say the sensors were a little dirty. It's a 2015 with 22k miles on it. I do wheel it, but is there a chance the sensors already went bad? Or maybe they got damaged during the gear install by accident?

Rednroll

It seems possible that the sensors had to be removed to do the gear install. Just from my own personal experience, I did a BBK install and had to remove the front sensors. After I re-installed the sensors I got the ABS light and tracked it down to my L/F speed sensor being faulty. I can't tell you what I did to cause the sensor to get damaged but it seems like it doesn't take much to damage them or could have just been some dirt/grease that fell into the sensor hole causing havok. After I tracked it down to the particular sensor, I replaced the sensor and cleaned out sensor mounting hole with a good dose of brake cleaner which fixed the problem. ABS light went off immediately, so I'm not sure if I buy the "drive it for 50 miles" suggestion.

If the ABS light is on, you can use an OBDII code reader which supports ABS codes and the code will usually point you in the direction of the problem. At least that is what I ended up doing. I went to an autoparts store which offered free code reading. However, the key is to find one that has a code reader which will read ABS codes, since most of the scanners will only read ECM codes.

BoraBora

Yeah I wasn't buying the "it'll reset after 50 starts."

Took a look under the rear, and the plug on the passenger side is clearly broken and they tried to zip tie it back together. Does anyone know where I can find just the plug? I'm going to take it back after 500 miles anyways and let them check the pattern.....and also fix my ABS they tried to bandaid.

BoraBora

Update on this:

Replaced the broken plug...lights were still on. Went ahead and replaced both rear sensors....still nothing. Ended up with new sensors all around. Lights on the dash are still there.

Every time I start the Jeep up and accelerate from a stop, the rear will lock up as if the ESP is kicking in on one side. Happens for 20ish feet, and then everything feels fine after.

Anyone have any idea what might be going on? I'm stumped.

cedarraider

Just a stab in the dark but I didn't see anything about a computer flash. Did you change the ratios with a flashcal or procal?

BoraBora

Yep, did that after the regear with my Pro-Cal. Although I did disconnect the battery twice after putting the new sensors in...do I need to flash it again?

cedarraider

I think once it's calibrated it's good. But it's quick and free to check it out.

Morghill

So I had the same issue with my 2007. Ended up leaving the gear ratio set to the stock setting, and only adjusting the tire size to fix the speedo. All the lights when off and the traction control quit freaking out!

BoraBora

Hmm, I'll give that a shot. My JK is a 6 speed....so ultimately it shouldn't matter if it's flashed to 4.56 right?

Edit: just tried...lights are still there and it still locks up. I feel like I'm chasing my tail here...really don't wanna take it to the dealer.

Morghill

Ultimately your right, but it worked for me, so it's worth a shot.