Gameblaster, if you head this direction over the next couple days, I can hook up my AutoEnginuity scanner and see what other modules are throwing codes...it might narrow it down a bit.

 

Yes please H2

I am so in need of fixing this ABS / Trac / ACS problem.

 

Quote:

Originally Posted by Gus

See if the attached procedure helps.

Hi Gus!

This document you posted really helped!

So I troubleshot what I believe is the problem with my ABS system.

Sometime ago an replacement ABS harness was installed on to the right wheel (Passenger Front). That cable stop having voltage during the test.

This is my procedures:
9V battery. Drill a hole in to the metal of negative plug. Loop in wire and secure. Loop in the positive side and secure.

Used the two leads into the end of any wiring harness. Use the multi-meter set to voltage to test for current in the harness. My voltage was 9.45 at battery. Through the harness was 9.37. Additionally if the harness is broken no volts will appear.

With the 9V battery in the ABS plug you can maneuver the sockets of the ABS in different positions to determine partial break in the wire.

Additionally, rotating the wheel and detecting voltage did not work for me. However, I am sure it would work with a mV (mill-volt) change, if you could spin the tire fast enough.

How to use a Multimeter:
http://www.wikihow.com/Use-a-Multimeter

Pictures:
http://mcdowpictures.shutterfly.com/pictures/20
http://mcdowpictures.shutterfly.com/pictures/19
http://mcdowpictures.shutterfly.com/pictures/18
http://mcdowpictures.shutterfly.com/pictures/17
http://mcdowpictures.shutterfly.com/pictures/16
http://mcdowpictures.shutterfly.com/pictures/15

Hope this helps!
James

 

So, with replacement of that harness, did the TRAC and ASC messages clear with it installed?

Did you try to measure voltage on both wheels thru the sensor itself (not the harness) when rotating the wheel, using your smallest value option on your multimeter for DC?

 

Hi H2OBoy,

That I could not do. I do not have any banana clips. I am sure it could have worked. I can test it out after getting some clips.

I think the resistance of the wire stopped it coming back to the harness.

 

Hi Everyone,

First I would like to thank H2OBoy for his time and uses of the auto computer AutoEnginuity.

Ok for the update.
RF had a bad harness in the voltage test. Replaced that ABS harness.
Swapped the Wheel sensors on the LF and RF.

After those changes I started to drive the car regular to work.
Day 1 Morning drive to work:
ABS light out! Yeah. 20 minutes into the drive the light come back.
Day 1 Evening drive to home:
ABS light still on all the way home.

Day 2 Morning drive to work:
ABS light out! Yeah. Almost the same place and the same amount of time, 20 minutes into the drive the light come back.
Day 2 Evening drive to home:
ABS light still on all the way home.

Day 3 Morning drive to work:
ABS light on!
Day 3 Drove to Matt house and hooked it up the computer:
ABS light on!
Cleared the codes and ABS light came back.

Codes are :
C1095 = Hydraulic Pump Motor - Circuit Failure
P1637 = CAN Link Engine Control Module/ABS Control Module Circuit/Network Malfunction
P1799 = CAN Transmission Control Module/ABS Control Module Circuit Malfunction
C1145 = Front Right Wheel Speed Sensor Input Circuit Failure
C1155 = Wheel Speed Front Left Input - Circuit Failure

We followed the Gus ABS doc.
The four lines to the Wheels did have a ohm of ~1.14. I was not in the tolerance. However, I would like a second opinion and if it is bad. Next plan of action.

While on ohm the RF and LF wheel did get spun and we saw the ohm jump from ~1.14 to ~0.92 and then back to ~1.14.

With the computer hooked up (Thanks again Matt). We drove the car to see the wheel speed. The LR (Driver rear) wheel sensor at times showed a difference of 1-4 miles slower than the other 3 tires. Is that in tolerances? If not change out the Wheel sensor?

So with the codes Matt made some great recommendations.

I do have another ABS module (good or bad ((it is used)) and connect it to see if that will cause the light to go out.
Swap LR and RR wheel sensors and see if the miles change. I can do this when I get a loaner on the computer.

I am crossing my fingers and hopping the best.
Because one of the options was a new ECM. Arg.

Please feel free to email me if you need any question or you have opinion or advice.

Gameblaster1

 

I think there may be an MY difference here. I have measured a fews cars and all have been, like yours, ~ 1K ohm, not 2K ohms.

The resistance jumping around like that is suspicious. Given this, with the intermittant nature of your fault, I think it's worth investing the time to open the connectors at the front wheel sensors, give them a good hose-down with contact cleaner, let dry, re-seat firmly.

Easy and free so worth a try. This has cured (at least temporarily) more than a few cars. Very weak part of the design.

 

And to add, after the clearing of the ABS codes, the only ones to reappear after restarting a few times and that little drive we took are:

C1095 = Hydraulic Pump Motor - Circuit Failure
P1637 = CAN Link Engine Control Module/ABS Control Module Circuit/Network Malfunction
P1799 = CAN Transmission Control Module/ABS Control Module Circuit Malfunction

Wouldn't it suck if you actually put a BAD abs module on your car from that used xj8...when the only codes you had previously, may have only been the wheel speed sensors and/or wiring?

 

Matt,

This whole area of front sensor wiring and connectors and the symptoms and the remedies ... must be a dozen threads now that touch on it.

FAQ-dom? (glad to get an oar in the water if I can help)

 

Update = No ABS light for 2 days. Woke up this morning to make the milk run. ABS light on when I start the car. ARG!

I am swapping out the old ABS module, this afternoon.

 

Hey dennis, yes...I know at least one or two threads are linked in the FAQ thread. It would, however, be nice to say...combine the very best posts, information, diagnostic process (you've given a couple good pieces, like the ABS light on upon start, as opposed to only after driving) and any tables/graphs/charts all on one thread...and let that replace the many that have been created. Since I have not personally diagnosed (with the exception of gameblaster's car) and resolved anything, I am not the best person qualified to make that creation. If you want the glory, you are welcome to it. If you want to draft something up, I'll be happy to FAQ that puppy!

 

Matt,

OK, how does this sound? I'd like to draft something restricted to diagnosing and fixing "in-motion" ABS/TRAC faults. Two basic types that I know of: 1) dirty sensors, 2) front (almost always front) wheel sensor connectors and wiring. The "fix" part would include a pointer to Sam's instructions on cleaning sensors and something cobbled together about the wiring & sensors.

Suggestion: If I then post this as a draft, people could comment, as in any thread, but then I could edit the initial post to reflect the comments and you could move just the edited, single post to FAQ-land (cleaner end-product that way v. a full thread, no?).

What do you think?

 

Works for me dennis! Since you have that electrical background, if you can throw in 'spec' range resistance for the sensors and the wiring harnesses themselves, that would be a huge addition, and of course, anything else of importance in that regard.

 

Gotcha.
And congrat's on your promotion. You buying drinks?

 

lol, new title, same pay...as in my life, this appears to be a pattern

Just spilled some coffee on the keyboard, cheers!

 

Update guys:
I put back in my other ABS module (known to throw the ABS code) back in to the Jag yesterday.

Arg ABS light came on. H2OBoy want me to drive it around a bit some more. But both modules are bad? Who knows, but I can tell you this. I am sending one off tomorrow to modulemaster.com. It has been repaired prior to me buying the car. They said they will not charge me if they can not repair the unit. (Very nice of them, I think).

Any opinions are greatly appreciated.
gameblaster1

 

All of these cars have had a history of Poltergeist syndrome. I would suggest pulling the plugs clean check for a tight contact and insert dielectric contact paste before reconnecting. I had one situation where the connection between the wire to the plug crimp connection was bad check that at the same time. It is possible that the ABS module is bad and you should soon find out now that you are having it tested. Hope this helps!

 

Has anyone considered it may be programmed incorrectly? As I recall some cars have ABS, some Stability Control (ABS & throttle manipulation), Traction Control (ABS, Throttle and individual brake manipulation) and, knowing Ford, some may (uncertain if a Jag option?) have a couple accelerometers involved for 'Save the Dumba** from Himself' control (known as StabiliTrak on Fords.)

My point being, if a used ABS module is swapped into a car without knowing which system is programmed into it odd things can occur, especially if it doesn't match the current programming in the ECU & TCU.

 

Have not given that a thought and my reason is that you can purchase a new one, install it and it works just fine.

 

I only asked gameblaster if the part numbers matched exactly...he said they did. BUT, perhaps the previous owner didn't sell the car with the correct module in the first place? I wonder who would know the correct part number...I suppose anyone with a 2002 should know.