Question about 2003 Jeep Grand Cherokee

1 Answer

ABS Light will come on only when it's raining or really damp outside...Why ??

Posted by on

  • fast One Aug 18, 2008

    After tearing apart and replacing the rear pads, I noticed the tone ring on the passenger side was covered with a greasy like substance. Axel seal and wheel cylinder are dry. Not sure whatthis greasy stuff was but I cleaned both sides with with brake cleaner, assembled the caliper assemblies and all is well. Thanks for the info..it helped alot.

  • burntchicken Aug 22, 2008

    Have a 1997 grand cherokee. This year after going through car washes and heavy rains the abs light would stay on and eventually go off and the system back to normal. This past 2 weeks, the abs light stays on all the time. Mechanic checked and shows fault of CAB(won,t clear). I've checked all fuses,both engine and pass. compartment. What's next?

×

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Novelist:

    An expert who has written 50 answers of more than 400 characters.

    Governor:

    An expert whose answer gotĀ voted for 20 times.

  • Expert
  • 72 Answers

My Answer:

It appears that very possibly you have a bad ABS wheel sensor either up front (right or left side) if you only have Disc Brakes in the front and drum brakes in the rear, or else a bad ABS sensor in one of the rear wheels with a 4 wheel Disc Brake system.

The damp part was the giveaway, as if it's doing it in dampness then surely it'll do it when wet as well. That is a given!

Esp if it's not doing it in DRY weather.

If it's not a bad (leaky as from moisture getting inside it) ABS wheel sensor then it could just be chaffed wires coming off from one of the wheel sensors that's shorting to ground. Esp when it gets wet as from dew point moisture or from rain. Possibly, but somewhat doubtful.

If you just had the brakes serviced recently, and the problem started shortly there afterwords then I would definitely suspect the (a) wheel sensor.

If it's been a problem from DAY ONE, or even under the original warranty period then it needs to be fixed for FREE under that original warranty. No bones about it.

What's probably happening is that the sense wire from whichever wheel sensor is bad is shorting out and causing the ABS FAULT LIGHT to come on. I seriously doubt that you will get a CHECK ENG code fault, as this is purely a BRAKE ABS fault.

One thing you might do is pull the main wiring harness connector off of the ABS unit itself and check it for MOISTURE on the contacts. If any is found then that is your problem point.

Even if no moisture is spotted get a can of waterproofing spray from you local automotive parts store and spray out both sides of the ABS wiring harness connectors.

Since this is purely a MOISTURE related ABS Warning Light issue/problem it has to be one or the other and nothing else.

Sometimes it's best to check for this issue at night with a good bright LED type light, as then the MOISTURE will show up better then in the daytime.

If this fixes the problem please post the result.

Frank

Posted on Aug 10, 2008

  • 1 more comment 
  • Frank JR
    Frank JR Aug 16, 2008

    One other thing I forgot to mention regarding the
    dampness/wet problem you are having with the ABS light is that if your
    brake pads are severely worn down then that too most assuredly will
    cause an ABS dash light to appear.



    You never said how many miles were on your present day disc pads??



    Frank



  • Frank JR
    Frank JR Aug 20, 2008



    In answer to that greasy stuff you found on the RR Speed Sensor Ring - no doubt it probably was 1 of 3 things.



    Either it was some sort of "road kill" - as in trucker's FOD (Foreign
    Object Debris) - in the form of whatever that may have dropped off a
    semi trucker's rig, or possibly it was brake fluid residue that was
    squirted haphazardly when whoever bled your brakes down the last time.
    That residue brake fluid then could have picked up road dirt, and then
    turned it further into that greasy mess you found. The other thing it
    could be is "road oil" like that what they use when they are re-paving
    an asphalt road, a parking lot, or street somewhere?? Who knows.....



    What I always do is high pressure (garden hose) the undercarriage down
    good every time I wash down my XPLR. Esp around the front disc brakes
    and the ball joints so as to "knock off" any built up crude there from
    excess ball joint grease etc.



    Same goes with the rear end area - only beings I have front wheel only
    disc brakes and drum brakes in the rear. I also run Ceramic brake pads
    in the front and my wheels stay pretty darn clean!!



    Glad you found the problem and all is well now.



    Thanks for the very knowledgeable feedback as well. I appreciate the post here!



    Happy driving now....



    Frank





  • Frank JR
    Frank JR Aug 23, 2008



    My answer to Burntchicken:



    Seeings your problem appears to be purely H2O related, as by what you are saying here - I really doubt you have a bad CAB or Controller Antilock Brake.



    There are a few preliminary things we can rule out right off the bat, unless they indeed prove to be true.



    1. Bad (worn out) brake pads (highly unlikely though)



    2. Excessively Wet or contaminated brake pads



    3. Low brake fluid (air enters into master cylinder and/or ABS HCU/ECU unit) as related to #1



    4. Bad master cylinder (piston rust) as related to #1&3 above



    5. Air and/or rust contamination particles inside the ABS HCU/ECU controller unit as from #3 or 4 above.



    6. Contaminated brake fluid as from #3-4 or 5 above, or from the fact
    that the brake lines were never bled down properly after each brake job
    (R&R of pads and/or shoes) for a very very long time, and now brake
    line contamination has set in from rust particles, or severely degraded
    brake fluid throughout the brake system.



    Note: (I myself personally worked on and fixed a similar brake
    related problem that had this same chain of events scenario below
    happen to a 1994 Ford XPLR with bad braking problems. Brake fluid
    probably was never changed in 10 years, and was so contaminated that
    the rear piston assys were shot, as well as 1 front wheel caliper plus
    the Master cylinder. The whole system had to be totally flushed 2 times
    over before clear fluid appeared at each wheel piston assy). All the
    XPLR owner ever did was have his buddy put new disc pads, or rotors, or
    else new shoes on the SUV, but that was all. Total sham job!!




    Reason I say this above is because you are saying it only throws the
    ABS HCU (Hydraulic Control Unit) light ON when your ABS HCU unit/assy
    with mounted ECU (Electronic Control Unit) gets wet - as you say.



    To me that is telling you that you are getting water on the ECU and esp
    the wiring harness connector(s)! Thus shorting it out and giving you a
    constant fault signal ON to your dash ABS warning light. I would
    seriously bet money your ABS unit is working OK if your brakes feel
    strong and solid and they aren't fading or pulsing all the time when
    braking.



    You should possibly be getting a DTC Service Code of B1432 with
    ignition key ON. Any other C code will then need to be further
    diagnosed and troubleshooted further as being legit or not.



    Before you can do that the following must first be done!



    I would first disconnect the wiring harness connector from the ECU and
    make sure it is PERFECTLY DRY and CLEAN from any or all H2O intrusion!
    Any removed "H2O resistant" connector contact grease must be replaced
    as per factory recommended spec! This is a must before the ABS system
    can even be troubleshooted properly.



    If your "mechanic" did not do this properly first of all - then he cannot for sure say the CAB is bad. Simply put.



    Let me know what you find after following the above procedures?



    Thx,



    Frank





×

1 Suggested Answer

FRANKSFIXIT
  • 72 Answers

SOURCE: ABS Light

My Answer:

It appears that very possibly you have a bad ABS wheel sensor either up front (right or left side) if you only have Disc Brakes in the front and drum brakes in the rear, or else a bad ABS sensor in one of the rear wheels with a 4 wheel Disc Brake system.

The damp part was the giveaway, as if it's doing it in dampness then surely it'll do it when wet as well. That is a given!

Esp if it's not doing it in DRY weather.

If it's not a bad (leaky as from moisture getting inside it) ABS wheel sensor then it could just be chaffed wires coming off from one of the wheel sensors that's shorting to ground. Esp when it gets wet as from dew point moisture or from rain. Possibly, but somewhat doubtful.

If you just had the brakes serviced recently, and the problem started shortly there afterwords then I would definitely suspect the (a) wheel sensor.

If it's been a problem from DAY ONE, or even under the original warranty period then it needs to be fixed for FREE under that original warranty. No bones about it.

What's probably happening is that the sense wire from whichever wheel sensor is bad is shorting out and causing the ABS FAULT LIGHT to come on. I seriously doubt that you will get a CHECK ENG code fault, as this is purely a BRAKE ABS fault.

One thing you might do is pull the main wiring harness connector off of the ABS unit itself and check it for MOISTURE on the contacts. If any is found then that is your problem point.

Even if no moisture is spotted get a can of waterproofing spray from you local automotive parts store and spray out both sides of the ABS wiring harness connectors.

Since this is purely a MOISTURE related ABS Warning Light issue/problem it has to be one or the other and nothing else.

Sometimes it's best to check for this issue at night with a good bright LED type light, as then the MOISTURE will show up better then in the daytime.

If this fixes the problem please post the result.

Frank

Posted on Aug 10, 2008

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Will not start when its damp out. when not damp starts right away thank u mike


Astro won't start or very hard to start when damp or rain ...

www.topix.com > Chevrolet Astro
Aug 24, 2007 - Posted in the Chevrolet Astro Forum. Leave a ... 2000 astro, Hardstarting or wont start when wet, once started its fine. I replaced the cap, rotor, gas filter, next rain was hard to start but did after about 10 tries. ... I have a 2000 astrocargo van. 4.3 v6. ... look for a faulty coil. mine passed out in a rainy day.

Van won't start in wet weather - Chevrolet Forum - Chevy ...

chevroletforum.com > ... > Past Chevy Truck, SUV & Vans > Astro
Sep 22, 2007 - I have a 1999 Astro Van and nearly everytime it rains or sometimes when I wash it, it will not start. ... I really like my ASTRO for everything from carrying family, boat, trailer, etc. but if it is not resolved its going before someone gets hurt. ...When it was damp out, the coil case would become wet, and the ...

Jan 18, 2016 | 1987 Chevrolet Astro Cargo

1 Answer

How do i fix a rough running after warming up in wet weather


I don't really know the answer, however, I would like to share my story with you, in case this happens to be the case with you. My older Volvo had all kinds of problems but only when warm and when it was wet outside. I had a mechanic that was throwing parts at it until my dad told me to go to an electrical specialist. He found out that the ground to the chasis of the car was not good, and in fact, when it was hot, it actually got red hot. The water aggravates electrical shorts. A bad ground is more common than most people think.

I hope that helps.

Apr 25, 2015 | Cars & Trucks

1 Answer

2000 gmc safari parked in the rain won't start


Did you take the distributor cap off and see if it has moisture inside ?

Apr 14, 2013 | 2000 GMC Safari

1 Answer

My 2002 Toyota Celica fogs up and collects moisture on the windshield during or after a rain. Visibility is a major problem. Need help, this is truly unsafe.


Can be that your heater core or hose inside car is sometimes releasing alittle heat at the clamps. So long the inside of the floor is not wet or damp or car is not over heating. I would not worry about the heater to much inside unless this does not work...
Change the automatic climate control up or down to cooler or warmer i usually run it at least upto 10 or 20 degrees different than the outside anytime i drive mainly during rain or snow.. So if outside it is warmer means you need to be cooler and cooler means get warmer. Also If you don"t run that on a regular basis a quick Ac on and defroster front and back works well and generally fast.I really think that is all of your problem just get comfortable with your automatic climate setting. once in a while it may happen again only because of rapid temp. changing from outside air to inside air in your car..Rain X works really well for a couple weeks between apps.and saves wiperblades during raining times. Always drive safely and good luck 11_21_2011_5_34_27_pm.jpg

Aug 16, 2011 | 2002 Toyota Celica

2 Answers

My ABS system check out OK during startup. ABS Light illuminates, then goes off. Have just installed new brake pads and rotors. However, when the car is coming to a stop, about 2 - 4 mph, it feels to me...


something as simple as a piece of string or trash can cause this, best to visually inspect the sensors, or do wha I do-go to one tof those carwashes that are do it yourself, and shove the high pressure wand (not too close) underneath near the inside of each tire, and clean the sensors off-sometimes a good drive int he rain works too, but it is not raining a lot here lately....

Jun 08, 2011 | 1999 Volkswagen Beetle

1 Answer

Car windows fog up so much if its raining or cold outside. turning on the air conditioner only seems to help.is there another alternative to this?


have a good look inside the vehicle as i suspect that their is a water leak into the car somewhere so its damp inside the car try lifting the mats and see if damp under the front carpets

Feb 15, 2011 | Honda Accord Cars & Trucks

1 Answer

The engine kills when it's wet outside (raining or just rained)


It is likely that your front oxygen sensor is getting wet.

Jun 18, 2009 | 2000 Pontiac Grand Prix

2 Answers

Astro vans that won't start if it's damp/raining outside


I have a 2000 Astro had the same troubles.I saw that the sides of the coil were burned looking.In between the bar that goes around it. This started around 110K It would run badly when wet or high humidity.Then throw up the check engine lite.Put on a new coil so far the problem has no reocured.

Feb 03, 2009 | 2000 Chevrolet Astro

2 Answers

ABS Light


My Answer:

It appears that very possibly you have a bad ABS wheel sensor either up front (right or left side) if you only have Disc Brakes in the front and drum brakes in the rear, or else a bad ABS sensor in one of the rear wheels with a 4 wheel Disc Brake system.

The damp part was the giveaway, as if it's doing it in dampness then surely it'll do it when wet as well. That is a given!

Esp if it's not doing it in DRY weather.

If it's not a bad (leaky as from moisture getting inside it) ABS wheel sensor then it could just be chaffed wires coming off from one of the wheel sensors that's shorting to ground. Esp when it gets wet as from dew point moisture or from rain. Possibly, but somewhat doubtful.

If you just had the brakes serviced recently, and the problem started shortly there afterwords then I would definitely suspect the (a) wheel sensor.

If it's been a problem from DAY ONE, or even under the original warranty period then it needs to be fixed for FREE under that original warranty. No bones about it.

What's probably happening is that the sense wire from whichever wheel sensor is bad is shorting out and causing the ABS FAULT LIGHT to come on. I seriously doubt that you will get a CHECK ENG code fault, as this is purely a BRAKE ABS fault.

One thing you might do is pull the main wiring harness connector off of the ABS unit itself and check it for MOISTURE on the contacts. If any is found then that is your problem point.

Even if no moisture is spotted get a can of waterproofing spray from you local automotive parts store and spray out both sides of the ABS wiring harness connectors.

Since this is purely a MOISTURE related ABS Warning Light issue/problem it has to be one or the other and nothing else.

Sometimes it's best to check for this issue at night with a good bright LED type light, as then the MOISTURE will show up better then in the daytime.

If this fixes the problem please post the result.

Frank

Aug 06, 2008 | 2003 Jeep Grand Cherokee

Not finding what you are looking for?
2003 Jeep Grand Cherokee Logo

1,463 people viewed this question

Ask a Question

Usually answered in minutes!

Top Jeep Experts

yadayada
yadayada

Level 3 Expert

61249 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6812 Answers

Are you a Jeep Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...