99 Rodeo ABS Module Wiring/Connector

I decided to start a new thread on this because I wasn't really getting any action when it was under the thread started by Solster (ABS recall ? reimbursement ?). Ryan, if you decide to nuke it, that's OK. I was just hoping that I could get some thoughts from some of you Rodeo vets, especially 2eyefishclaw who is EXTREMEMELY knowledgeable.

So here goes: I have been plagued by an incessant ABS light for the last several months. The brakes work fine except there is no ABS. It's just that little light on the dash taunts me!!!

I used the link posted by LetsRodeo in another thread to query the ABS computer and got the following error codes.

52 FR Open or Shorted Sensor
62 FR Missing sensor signal/FR Sensor Signal Dropout
51 FL Open or Shorted Sensor
61 FL Missing sensor signal/FL Sensor Signal Dropout
53 Rear Open or Shorted Sensor
63 Rear Missing sensor signal/Rear Sensor Signal Dropout

It seems odd that all three sensors would be bad at the same time and since there are three different wiring harness segments involved, I'm skeptical that it's a wiring harness issue. I have a wiring diagram for the ABS system and there doesn't seem to be any common wiring between these three sensors. The only thing they seem to have in common is that they all connect to the ABS module within the same connector. Maybe there is some corrosion here?

I have tried to remove the big connector from the ABS computer with the thought of removing the connectors at each sensor and shorting the wires on the sensor end and checking for continuity at the computer end. The problem is that the connector does not come out easily and I'm afraid to pull on it too hard for fear of messing it up. Is there a secret to getting this connector off?

Thanks in advance for any insights into this problem.

JWS
99 LSE 4WD

It almost sounds like the ABS system is not getting any power. Did you try swapping the fuse and/or relay? Might be something to look into.
G/luck
Joel

there is a relay problem in the ABS module your ABS module should fall under the recall e-mail me your VIN # I will let you know if it is

Well, I e-mailed 2eyefishclaw my VIN as requested but I never heard back from him (maybe the e-mail address in your profile is out of date).

Once I downloaded the full service manual that marcre posted the link for (thanks for that, marcre), I found out how to get the aforementioned connector out of the ABS module. From there it was pretty easy to check out the wiring.

I did find one flakey connection going to the rear sensor, which I fixed. I the put the whole thing back together and tried to do the self-diagnostic. This time, in addition to all the same codes I got before, I also got code 14 -- several items all suggesting the ABS module might be the issue. Repeated attempts to clear the codes using the brake pedal method or even removing the ABS fuse overnight were unsuccessful, leading me to believe that the module might, indeed, be toast.

I found a new ABS module on ebay (price was good enough that I bought two). I replaced the ABS module. Lo and behold, the ABS light has been extinquished and performing the diagnostic returns no codes! HOORAY!!

Now I'm just waiting for it to rain so I can see if the ABS actually works!

I've only had my Rodeo for a little over a year. I checked with Isuzu right after I bought it to see if the ABS recall had been performed and the answer was 'yes'. The ABS module I removed did not seem to be the factory one since it had a 'Service' sticker with bar code on it. It looks like it is actually a GM part made by Delphi. Anybody know if there was ever a bad batch of these? My 'zu now has it's third module. Maybe it's a good thing that I bought two?

JWS
'99 Rodeo LSE 4WD

I got the intermittent abs light after the abs recall and now the light is on all the time. before the recall I didn't notice any problems with the abs and of course never had the abs light come on. this really bugs the crap out of me, I've heard the same story from a few other people after the recall, and some people have the problem with no recall. I'm aware some of these issues are wiring issues but believe some of these abs modules are bad in general, it's really not fair to get such a low qaulity part. Isuzu should really work on getting this taken care off. out of all the things Isuzu decides to turn a blind eye to, the abs shouldn't be one of them.

Well, I agree the ABS is one of Isuzu's weak points along with the high oil consumption on some 3.2's (mine is one of those, sadly).

However, it is pretty easy to diagnose the ABS wiring if you have the right doucumentation and a digital multimeter. Maybe I'll write up a procedure sometime for Ryan to post...

That said, I'm not sure whether it is better to have ABS or not. Most of the people I've ever talked to or read about who have had an accident with ABS report that the increased stopping distance caused by the pulsing of the brakes probably played a role. Before my ABS died I did notice that it sometimes took longer to get stopped in wet weather. Good old fashioned brake pumping may be a better way to stop on slick surfaces.

I mainly wanted to get my ABS back up and running just in case I wanted to sell my truck. With gas prices approaching the stratosphere, my Rodeo has become much less affordable to drive.

Of course, I would think that those same gas prices have really slammed the resale value of any vehicle which goes by the initials S.U.V so maybe I will just hang on to it and learn to eat less (which would actually be better for me...)

As far as the bad module is concerned, I would be interested to to hear from any others who have had to have their module replaced for whatever reason.

Hello! This is my first post on this forum. I own 2 98 "Honda" Passports. One is an EX and the other an LX. The LX has been nothing but a nightmare and the EX is staring to be a pain right now. The ABS light popped on about 2 weeks ago. The mechanic diagnosed it and said it was the ABS control modual. I had it replaced and the light came right back on? Is there a way to clear the codes or reset the computer? I'm hoping it's something that and not something that will cost me $$$$$! Any ideas are appreciated!!!!

Since JWS mentioned the thread I (SOLSTER) started, I thought I'd link it for future reference:

http://www.automotiveforums.com/vbulletin/showthread.php?t=354161
Although, that thread is about ABS wiring harness, and ABS in general.

You can also go here:

http://forums.klipsch.com/idealbb/files/ABS%20DTC.pdf

It's pretty easy to run this diagnostic. I was never able to get my codes to reset but I think it was because the module itself was toast. If you are still getting the ABS light after having the module replaced, you probably have a bad sensor or wiring. But if this test shows multiple codes, you may have a bad replacement module.

The ABS system on these 'zu's is not all that complicated to understand and I thought it was pretty easy to troubleshoot once I uncovered enough info about it. Post the results of your diagnostic and let's see if the community can figure it out.

JWS
'99 LSE 4WD just turned over 100K this morning!

Hi everyone - here's my first post on my ABS woes...1998 Passport 3.2L EX.

Its my wife's car, but as I undertand the ABS light just came on one day. It might have been intermittant at first - she's not sure. I added some brake fluid as it was a little low (about MIN level). The light went out after driving a while, then came back on and has remained on ever since. Driveability seems fine.

As with the first poster, I used the tip from LetsRodeo to pull codes, and I got a lot of them as follows:

35 Shorted relay circuit
41 Open/shorted FL isolation solenoid or ECU output
42 Open/shorted FL dump solenoid or ECU output
43 Open/shorted FR isolation solenoid or ECU output
44 Open/shorted FR dump solenoid or ECU output
45 Open/shorted Rear isolation solenoid or ECU output
46 Open/shorted Rear dump solenoid or ECU output

These suggest to me that either the module connector is bad/dirty or the module itself is toast. Codes won't clear - they stay set, so problem still exists. Any ideas?

As an aside, I have an Actron code reader that gives Powertrain, Chassis, Body and Uart codes but when I tried it for the ABS it read nothing. I haven't researched why that is, and its not overly important with the jumper wire trick, but I'm curious just the same.

Lastly, we're in the "high oil consumption 3.2L" club and the "thumping slip yoke" club, which I intend to fix per the helpful forum posts asap. Good vehicle otherwise so far - owned for 2 years and 50k to 85k.

TIA,

-Keith

It does, indeed, sound like your module is toast. One thing you might try is to pull the power connector (2 wires) off the module and use a piece of wire to short the power terminals on the module. This should clear its memory. Then plug the power back in and see what happens.

If you need a module, try ebay. I bought two of them NIB back in February. The guy had about 20 of them then. He may have sold them all since then. Come to think of it, his were all for 4WD drive models and the modules are not interchangeable (don't really know why).

Good luck and let the rest of us know how it turns out.

Thanks. I tried shorting the power terminals per your suggestion, but it made no difference. I did find the modules on Ebay - brand new 4x4 (which is what we have) for under $60 delivered. Thanks for that tip - I'd have grudgingly paid the $200 dealer charge otherwise.

I will advise once I get it installed as to whether that solves it.

Thanks. I tried shorting the power terminals per your suggestion, but it made no difference. I did find the modules on Ebay - brand new 4x4 (which is what we have) for under $60 delivered. Thanks for that tip - I'd have grudgingly paid the $200 dealer charge otherwise.

I will advise once I get it installed as to whether that solves it.

New module works great! :bigthumb: Nothing to it really. I tried reading my new Haynes manual before installing, but it just told me to take it to the dealer...how helpful.

Also greased the slip joint with moly multi-purpose grease (couldn't find Red Crown). No more driveline thunking.

Great news! Yeah the module is pretty easy to install if you have the right tools. I found it a little difficult to access those Torx screws.

As for the Haynes manual, I have one too and it's pretty worthless on the ABS. I guess they don't want to get into it because of the potential liability issues.

Glad you got your rig fixed. How big a job was it to get the drive shaft apart and lubed? I've got the clunk too.

Ditto on the torx screws.

Driveshaft wasn't bad either - except I needed my 1/2-inch air impact to break the 14mm nuts loose! (I didn't use penetrating oil in advance though). Just scribe the housings front and rear so it goes back the same it came out. I used 3 zip ties together to put the slip joint cover back on, and tried to evenly space the heads of the ties for balance. Dunno if that was worthwhile or not, but made me feel better. Took me an hour - including hunting for sockets and wrenches :).