when an abs sensor goes bad

[new jeep owner]

how do you know which one it is ?
my abs light and my esp light came on after making a quick stop. and they
are staying on .
I checked for codes, but there are none coming up.

 

[diyman]

First of all, don't despair

And Yes, You'd need a really smart scan tool to read the proper code

But, before You p: .... do the following: if space is too tight for you, lift the rear axle a bit,
then, just above the diff, there is a connector which, 90% of the times, is the culprit!
Remove it CAREFULLY, connectors don't come cheap, clean it with contact spray,reinstall and
cross fingers....

I've heard cases where oxidation formed on the ABS unit side, but some contact cleaner did the trick!
Connectors (2 IIRC) are a in an uncomfortable position however....so, leave that as the last resort...

Unfortunately, front wheels' sensors are a PITA to access, You'll need to almost remove the hub..
They're about 40 U$ each and RH/LH are different, as usual....

 

[new jeep owner]

thanks I'll try that this afternoon.

 

[diyman]

Oh, BTW, check for snapped cables as well... happened to me once (RH sensor) :disgust:

 

[Atrus]

Oh, BTW, check for snapped cables as well... happened to me once (RH sensor) :disgust:

Me too - and "snapped" doesn't mean visibly broken (unfortunately). It can be broken internally and not show any issue. Mine was shot on the passenger rear - I had to rebuild it.

 

[speedracerbubba]

if it turns out to be the front passenger side I have an old one that came out of a hub that had a bad bearing.

 

[new jeep owner]

took the back ones out and cleaned them. man were they dirty. if I pull the rotors can I see where they make contact?


I'm thinking it may be one of the back ones, as the traction control hasn't been working right lately.

the cable looks good. on the outside at least, how do you know if its bad inside? or do you ?
I haven"t checked the front ones yet, too wet right now.
rain and no garage= no fun

 

[diyman]

New Jeep Owner, sorry for misguiding You, but my KJ (MY '06) was assembled here and apparently still used a MY 2005 layout,
therefore ABS system is a three-channel one, std for '05 IIRC. So, no separate rear wheel speed sensors for me.

I can only guess the four-channel was standard with traction control....glad I don't have it then

Anyway, as You're talking about rain, chances are it's just an issue of moisture/oxidation, almost sure it's nothing serious.