Intermittant ABS light '93 GC

Recently I have been getting an intermittant ABS light in my 1993 GC.
Started seeing the light for the first time intermittantly during a
500+ mile trip (in 90+ deg weather) about two weeks ago.

The indicator light usually goes off after starting but sometimes it
will stay on from start up (i.e. it doesn't come on after moving or
anything like that). I checked the ABS module connector
(clean/spotless), the ABS fuses, ABS sensor connectors, and cleaned off
the sensors. The front toothed wheels are pretty rusty after 120Kmi.

I presume the only way to find out what's wrong is to have someone scan
it but I was wondering if anyone has any other hints.

WB

Many auto-parts stores (ie. AutoZone, Advance Auto Parts) will scan your
error codes at no charge.


> wrote in message
oups.com...
> Recently I have been getting an intermittant ABS light in my 1993 GC.
> Started seeing the light for the first time intermittantly during a
> 500+ mile trip (in 90+ deg weather) about two weeks ago.
>
> The indicator light usually goes off after starting but sometimes it
> will stay on from start up (i.e. it doesn't come on after moving or
> anything like that). I checked the ABS module connector
> (clean/spotless), the ABS fuses, ABS sensor connectors, and cleaned off
> the sensors. The front toothed wheels are pretty rusty after 120Kmi.
>
> I presume the only way to find out what's wrong is to have someone scan
> it but I was wondering if anyone has any other hints.
>
> WB
>

barie did pass the time by typing:
> Recently I have been getting an intermittant ABS light in my 1993 GC.
> Started seeing the light for the first time intermittantly during a
> 500+ mile trip (in 90+ deg weather) about two weeks ago.
>
> The indicator light usually goes off after starting but sometimes it
> will stay on from start up (i.e. it doesn't come on after moving or
> anything like that). I checked the ABS module connector
> (clean/spotless), the ABS fuses, ABS sensor connectors, and cleaned off
> the sensors. The front toothed wheels are pretty rusty after 120Kmi.

Checked <> Cleaned

It may look just fine but be salted up and causing problems.


--
-- DougW -- 93 ZJ 4.0 http://members.cox.net/wilsond
HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks
Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors
Banks Header - and BEER, in the fridge!

I'm just really surprised it's still working:
http://www.ifsja.org/tech/index.shtml
God Bless America, ßill O|||||||O
http://www.billhughes.com/

wrote:
>
> Recently I have been getting an intermittant ABS light in my 1993 GC.
> Started seeing the light for the first time intermittantly during a
> 500+ mile trip (in 90+ deg weather) about two weeks ago.
>
> The indicator light usually goes off after starting but sometimes it
> will stay on from start up (i.e. it doesn't come on after moving or
> anything like that). I checked the ABS module connector
> (clean/spotless), the ABS fuses, ABS sensor connectors, and cleaned off
> the sensors. The front toothed wheels are pretty rusty after 120Kmi.
>
> I presume the only way to find out what's wrong is to have someone scan
> it but I was wondering if anyone has any other hints.
>
> WB

Which one may look fine but be salted up? I presume you mean the
sensors and/or their connectors. In my case the big ABS module 40+pin
connector was pristine. It looked like no water or anything had ever
gotten into it.

barie did pass the time by typing:
> Which one may look fine but be salted up? I presume you mean the
> sensors and/or their connectors. In my case the big ABS module 40+pin
> connector was pristine. It looked like no water or anything had ever
> gotten into it.

Any of the connectors but usually it's the big connector on the ABS
computer. http://www.revbeergoggles.com/Fixes/computer-abs.jpg

It might look fine but it's probably not. The 93 ZJ drains water
from the hood right down on the top of that connector and it's
subjected to air/road stuff that makes it in past the seals around
the intake and left headlamp.

The place stuff gets into is under the connectors hood where the
wires go in. If you take the back shell off and tap it you will
probably see lots of dirt fall out. That's the side that gets
contaminated with road salt/etc and develops small current leaks
between wires. Since the ABS sensors are so sensitive, even the
smallest current leaks can cause problems.

Usually have to clean mine about once every 2-3 years.

If you take the air filter top off and remove the filter, that
spot makes a good location to set a plastic bag and clean the
connector. You don't want to use connector cleaner over paint
as it's also good paint stripper. The bag and a paper towel
catches the excess fluid/debris.

The stuff I use is TechSpray, Econoline Contact Cleaner #1622-10S
(Safe on _most_ plastics) Connectors are ok, soft rubber
or vinyl tape ... that's another story...

I usually pull the ABS computer fuse before working on that connector
although contact cleaner is non-conductive. If you use a brass brush
to clean the connectors make sure you vac and examine for loose bristles.

--
DougW

Ok I'll take a look at the backside of big connector where the wires go
in this weekend.

Thanks,

WB

In case anyone is still following this thread. I finally found the
problem. I cleaned up the main connector but still had an intermittant
ABS light all last week. I started ohming out the sensors when the ABS
light was on and the problem was an intermittant right rear wheel
sensor. Sometimes it was fine and other times is was bad. It would
read 1.1KOhms (which is OK) sometimes, 1.8KOhms someother times, and
open once in a while. Replaced sensor and everything seems ok so far.

WB