ABS Light came on - 99 Intrepid

Well today it happened to me. I had last used the car Friday night and
all was well. This morning I start it up and the ABS warning light was
lit. The TRAC Off light was also on for good measure as a reminder the
traction control system is part of ABS. I was hoping that it was just
an anomaly, but the light has remained on. Turning the key on 3 times
fast does not yield any codes, although ABS codes probably wouldn't
appear in the odometer.

I've done some searching but I didn't see that this was a common problem
or any good solutions. I'm guessing (hoping!) one of the speed sensors
is bad. (I expect they are just regular hall effect type sensors, but
is it possible they can make a noise when bad? I have heard a noise
from the front wheel get louder lately, but my mechanic said all was
well). I'm sure it will have to go to the mechanic for fixing, but
I'm curious if I can find out what the problem is first.

My front brake pads/rotors were replaced just under 2 months ago, is it
possible that something bad could have happened then that just now
caused an ABS fault?

Does anyone know of a decent OBD II scanner that can retrieve the
proprietary Chrysler codes? I've been thinking of buying one,
especially if it can get access to the realtime engine data.

I'd appreciate any insight/advice.
Thanks!


antilock brakes warning light LH

 

Recently I've got my Chrysler OBD II codes with a reader, bought from
Canadian Tire for about $250. The model is Inova 3100 code reader,
product# 25-1030-4. It can display only the codes without eplanation.

here is a link:
http://www.canadiantire.ca/assortme...303517520&FOLDER<>browsePath=1408474396669497

 

Recently I've got my Chrysler OBD II codes with a reader, bought from
Canadian Tire for about $250. The model is Inova 3100 code reader,
product# 25-1030-4. It can display only the codes without eplanation.

here is a link:
http://www.canadiantire.ca/assortme...303517520&FOLDER<>browsePath=1408474396669497

 

The INNOVA 3100 does not pull ABS codes on my Ford Windstar. I wish it did.
My 3100 came from Wal-Mart at just under $100 US.

 

Recently I found these steps regarding the OBD scan cycle:
http://www.obdii.com/drivecycleford.html

Did you do some of them?
Did this Inova 3100 show you any codes on your Ford?

 

I did not do the drive cycle scan as shown on the link you provided. I just
plug the scanner in, start the engine, start the scanner and go.

Yes, the INNOVA 3100 gives me Ford specific codes as well as the generic
OBD-II codes...but no ABS codes.

 

Greg -
Sorry I missed seeing your post until just now.

It sure seems coincidental that you're suddenly getting wheel noise
about the time you're getting an ABS light. The sensors would not make
noise when going bad. However, maybe there is something mechanically
wrong that has damaged the sensor and that whatever did that is making
the noise. You probably already know that the sensor is mounted in a
hole in the steering knuckle aimed at a toothed wheel (which spins with
the axle) integral with the wheel bearing.

Also, what is the noise like? If it is a high pitched squeel that is
present mostly at low speeds, it could be that the rotor shield (a sheet
metal flag that hangs down between the control arm ball joint and the
rotor) is bent and is rubbing the rotor. That is not uncommon to happen
when brake work is done on the LH cars - occasionally here and on other
LH car forums, people post in complaining of such a noise, and it turns
out that that is the problem. That would not explain an ABS code, so
this would be the case if the two things (the noise and the light) are
unrelated unless someone were really careless during that brake job and
messed up more than one thing.

You might get a second mechanic to check the wheel/brake area out - I
mean, either there *is* a noise or there isn't, and if there is, a
mechanic should be able to pinpoint it and identify the cause (I'm
assuming it isn't intermittent, which if that were the case, he maybe
could be forgiven for not being able to find it).

If it's a rumble that changes pitvh with vehicle speed (and gets louder
or more quiet when turning in one direction or the other), that would be
a bad wheel bearing.

If nothing I said above rings a loud bell, post back with more
description of the noise, and we'll go from there.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

Hi Bill, thanks for the input. As you were writing that, I was driving
the car home from the mechanic. He used a snap-on tool and diagnosed
the rear left wheel had the problem. He then found that the speed
sensor there was not producing any voltage. The part needed to be
ordered and came in the next day (I assume he ordered it through a local
Chrysler or Dodge dealer; I didn't ask). Before I took it in, I did
note from my (somewhat stale) parts catalog that '98 and '99 LH cars
have a separate part number for each wheel sensor, so that must be a
pain to stock. He agreed with that. (I think '02 LH cars have just two
part numbers, front and rear).

I should have asked if the sensor looked rusty (likely) or it just
failed, a la the transmission speed sensors, which are probably the
exact same thing in a slightly different size. It is funny that one
day it worked fine (I had been running errands, and the last trip was
short) and then Monday morning the sensor was marked bad before the
wheel even started rolling.

I was very happy it was just a sensor. (The front tone wheels require
the driveshaft to be replaced!) It still cost over $200 to replace (if
it had happened last year, my Added Care warranty would have picked up
the tab) by the time the diagnostic fees and the part costs were taken
care of. I'm not sure if it was cheaper here or at the dealer, but my
Dodge dealer always acted as if the customer was dumb, so I preferred my
local guy. Oh, he balanced the front wheels, as I had noticed a
vibration after I rotated them earlier this month. Chrysler thinks its
wheel weights are special and there is a TSB for their handling, I"ll
check this out tomorrow.

I can probably expect the other 3 sensors to go south too, and it
sure would be nice if I could get those codes myself. I hear that the
newer C.A.N. OBDII protocol has more open codes, including ABS, airbag
sensors and the like, does anyone know? At any rate, my '99 is too old
for CAN.

Regarding the front wheel sound:
I don't think it's a rumbling sound. I'm very familiar with the rotor
rubbing heat shield situation (I think I was the charter member of that
discovery club but the symptoms here are different (and my front
rotors are now brand new. The squeaking sound may not be a big deal,
perhaps I'm nitpicking, but it definately didn't use to make that noise.
More to come on that...

Thanks
Greg

 

Yeah, unfortunately the basic OBD II tools can't communicate with the
ABS module. As far as I know, all of those codes are proprietary and
you need either the factory scanner (Chrysler calls theirs the "DRB III"
) or Snap-on makes one for mechanics (very expensive).

 

I don't think wheel speed sensor failures are all that common on the
LH's - certainly not to the point I'd expect multiple failures on one
vehicle over it's life. I own two Concordes and have never had one go
bad, and just don't recall reading of very many such failures at all on
the 300M or Intrepid forums.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

I can't disagree with that, I haven't seen many reports of ABS sensor
failures either (and I was looking all over the place for them after my
ABS light came on). I figure if a sensor like that fails it is most
likely due to corrosion or the environment near the sensor. (I live in
the salt belt).

However, I don't think those sensors are that different from the
transmission speed sensors, at least in theory. And we know *they* go
bad relatively often, despite they are arguably in a less corrosive
environment than the wheel hubs. Perhaps the ABS sensors however are
made by ABS vendor (Continental Teves?) while Chrysler used another
vendor for the the lousy transmission speed sensors.

By the way, are there still different part numbers for these trans.
speed sensors based on the year of the LH vehicle? I recall the part
numbers were different from '98/'99 LH to '02 LH, but I've also heard
that Chrysler used the same speed sensor part numbers for many models of
cars (outside the LH series) and they haven't been updated.
Unfortunately my '99 LH part catalog is getting pretty stale, I think it
was printed in '02 or '03.

 

greg just so u know in michigan now, you can buy a new axle for that car for 55
bucs. hell a boot kit for that axle is 35 bucs and the new axle comes with a
tone wheel

 

I can't explain why - only that I don't see evidence of wheel speed
sensors going bad all that much, whereas the tranny speed sensors are a
common failure item, as you agree. They do see heat, and the are a
different part, and as you suggest, possibly a different supplier, so
who knows. My theory is that their magnets gradually get weak until
their signals drop below the trigger threshold of the electronics -
further evidenced by typical behaviour at failure being intermittent
(work when first started up, fail later, or vice-versa, work in cooler
weather but not in warmer weather, etc. - all indications of a very
marginal signal undergoing small changes due to environment.

I also mis-spoke earlier - as you pointed out the tone wheels are on the
outer axle joints, not on the bearing as I had said.

The parts listings that I have access to for '98 thru '02 - all released
in March or May '02 - show *all* 2nd gen LH as the same part numbers
(input 4800878, output 4800879) except '98 shows different numbers
(input 4412878, output 4412879). *BUT* when I plug the numbers into an
online dealer site parts lookup, the '98 part nmubers show as having
been superceded by the later numbers. So - no, the parts weren't
different for different years - I think they've always been
interchangeable - perhaps it is a different supplier. Hopefully they
actually improved the part (and/or supplier) to fix the gradual decay of
signal and ultimate failure to be read by the TCM (or PCM in later years).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')