ABS & Tone Ring issues

[Jim Oaks]

My 2005 Jaguar XJ8 is giving me an ABS light. I replaced the right front wheel speed sensor but I'm still getting a code. I scanned the ABS codes and got:

C1142 - Front right wheel speed sensor tone ring tooth missing fault
C1145 - Wheel speed front right input circuit failure
C1234 - Front right wheel speed signal comparison fault

I took the hub assembly and looked inside the port for the sensor and saw this:

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I'm a little confused by this because I was expecting to see metal vanes, not a smooth surface. Seems unlikely to me that this could be bad, so I'm looking for input from anyone that has dealt with this type of tone ring before and how I can determine if it's bad.

 

[85_Ranger4x4]

I wouldn't worry about it, the light will go out eventually.

 

[Curious Hound]

I wouldn't worry about it, the light will go out eventually.

Oh, there you go again.

 

[Curious Hound]

It's more work, But you could take a look at another tone ring for comparison. The tone ring might have the actual "toothed wheel", made of steel, encased in a smooth aluminum piece so you don't actually see the teeth.

Being a performance/luxury car, they may have e done that so the teeth dont make noise as they spin in air like a fan blade. Yes, it's more expensive to build. But, those are the kinds of details that make luxury cars what they are. The sensor would still pick up the ferromagnetic teeth just fine.

 

[pentode]

Just brainstorming here … in order to confirm the wiring and/or sensor are good, if you can get it on jackstands or a lift, you can run jumper wires across to the other side to see if the fault follows. Hard to orchestrate on the road.

edit: real time sensor data is extra helpful for that test if you have it.

 

[Curious Hound]

Just brainstorming here … in order to confirm the wiring and/or sensor are good, if you can get it on jackstands or a lift, you can run jumper wires across to the other side to see if the fault follows. Hard to orchestrate on the road.

edit: real time sensor data is extra helpful for that test if you have it.

I agree. Actually, if they aren't difficult to replace, just swap sensors from side to side and drive it. If the problem moves to the other side, bad sensor. If the problem stays in place, bad tone ring. If the problem goes away, ?????

There isn't much that can go wrong with the tone ring. Usually, that would indicate a wheel bearings problem affecting the spacing betelween sensor and ring.

 

[Uncle Gump]

05 should be OBDII...

Look at the data while driving

 

[Bill]

I had a similar issue with my Ranger. The ABS sensor went bad on one side, so I replaced it and everything worked as expected. A year later the problem occurred again on the other side. So, I thought it would be an easy fix and I replaced it. It worked for several days, then the problem came back. When looking up troubleshooting steps I reads some posts on another Ford Truck forum where the ABS sensor picked up ferrous material when driving on forest roads not far from here and the ABS sensor had magnetized the metal around it. That caused the ferrous material to accumulate around the hole the ABS sensor sits in. Since i had been in the same area camping just prior to this happening to me I took a look and saw a lot of it on and around the ABS sensor. Once I removed it everything worked normally. Basically, what happened is the ABS system was able to determine that an irregular signal was coming from one of the sensors (the signal from both sensors should be roughtly the same) and the light came on.

 

[Jim Oaks]

I have two thoughts:

1) I had trouble getting this sensor to seat all the way down into the hole. A spring clip snaps over it to hold it in place. I'm wondering if the gap between the sensor and tone ring is bigger than it's supposed to be and causing a problem. Probably unlikely.

2) The wheel speed sensor has a long cable that plugs in to another cable behind the wheel liner. I feel like I may need to check the cable behind the wheel liner and ensure the sensor has a connection back to the module.

I need to figure out how to test this while the hub is off the car. I don't want to put it on just to have to take it back off.

 

[scotts90ranger]

Sensor gap could definitely be the issue, sensors have varying gaps they can deal with, crank sensors at work are generally .005" to .050" (listed in the metric equivalent but I don't remember that...). Then you get into the different types of sensors, VR and hall effect, VR are usually 2 wire and simpler to make but harder to read as the signal they give varies in amplitude (voltage) and frequency depending on the speed of the reluctor wheel... A hall effect sensor gives out a more simple fixed amplitude square wave but are 3 wire normally. VR sensors usually require more shielding on the wires for noise suppression than hall effect.

That said, gap could definitely do it, but so could a compromised wire...

 

[sgtsandman]

One possibility, some tone rings are glued on. The glue eventually fails and a chunk of the tone ring falls or gets ripped off. I think it is more of a GM thing but being that we're talking about a Jaguar, who knows. Pull the sensor and spin the hub to see if the surface changes.

Another possibility, though the seating surface doesn't appear to be that bad, is maybe what corrosion is there is moving the sensor just enough to cause a reading error. Cleaning the surface up with some emery cloth and making sure there is nothing in the hole itself will make sure it isn't a seating depth issue.

 

[Jim Oaks]

Today I replaced the wheel hub. The new hub came with the speed sensor but the cable was a couple inches to short, so I reused the sensor that I recently bought. I drove it a block, and the ABS light came back on.

I drove it and checked the live data. The right front was displaying low erratic numbers. Twice when I hit a dip it seemed to jump up to the right spoed briefly, so I'm wondering if I have a short.

 

[pentode]

I was thinking wiring before... bump = better data really makes me wonder.

 

[Curious Hound]

Possibly a loose connection or damaged cable somewhere.

 

[Jim Oaks]

Swapped sensors. Still no input. Is there a way to test the connector that the wheel speed sensor cable plugs into? I know it's a 2005 Jag, but this was built when Ford owned Jag and some things interchange.

Looks like I can get a new connector and cut off the old one.