Wheel speed sensor , ABS module or possessed

[Donut707]

On my drive into work this morning the jeep had an interesting fault . The speedo was erratic and the all ABS, EAS and ABS lights were flashing and the chiming. I had a abs light on intermittently a while ago but never long enough for a code to be detected ( odd) . I'm suspecting one or more wheel speed sensors , or the ABS module has or is begging to fail.
2008 JKU

 

[jeeeep]

On my drive into work this morning the jeep had an interesting fault . The speedo was erratic and the all ABS, EAS and ABS lights were flashing and the chiming. I had a abs light on intermittently a while ago but never long enough for a code to be detected ( odd) . I'm suspecting one or more wheel speed sensors , or the ABS module has or is begging to fail.
2008 JKU

auto parts store should be able to read the codes if you don't have a reader, should be able to tell you which sensor is bad if that's the issue but
could also be cut/chewed wires (rodents) or tone ring.issue.

Don't recall the sequence but you can also do a key sequence to show the codes on the dash, I believe where the mileage indicator is.

 

[wayoflife]

Have you checked to make sure that your battery leads are on securely? A loose one or even a ground will cause what you're seeing.

 

[Donut707]

My jscan didn't detect anything . I will double check the battery connections. My local shop has a snap on scanner they let me play with , so ill swing by there at lunch to see if it picks anything up . ive has wheel speed sensors and even a bacd unit bearing before give a abs light on steady. the speedo all erratic was a first , the jeep drove fine no other issues or indications of anything else being wring.
thanks for all the input , ill report back what i find

 

[wayoflife]

jscan won't pick up a loose lead. The battery leads have conical nuts that create compression on the clamps. If you've installed something like a radio or compressor and attached a ring terminal between it and the clamp, that would prevent it from tightening it well. Of course, that is just one example of what can cause a loose lead. For the most part, the lead will be fine but a bump in the road can cause a momentary separation and that will cause the erratic lights going on and other issues you see. Not saying this is what you've got going on but I have personally seen this happen and on lots of JK's including my old 2012 that I used to have.

 

[DirtHeadDavis]

What @wayoflife said. I had a similar issue a while back and it was literally just the negative terminal lead. Moved my accessories to a different post and tightened the conical nut back down. Hasn't happened since.

I did also have the ABS and traction light on solid on a separate occasion, but not flashing or with a wild speedo. That turned out to be the wheel speed sensors.

 

[DirtHeadDavis]

auto parts store should be able to read the codes if you don't have a reader, should be able to tell you which sensor is bad if that's the issue but
could also be cut/chewed wires (rodents) or tone ring.issue.

Don't recall the sequence but you can also do a key sequence to show the codes on the dash, I believe where the mileage indicator is.

Also this ^

Turn the key three times to the accessory position quickly. Dashed line will pop up where the odometer is and show you the currently stored codes followed by "done"

 

[Cousin Clyde]

Agreed on battery terminal. The speedo jumping all over the place is the most consistent symptom that I have had on my JK, caused by the loose terminal.

Even if the negative terminal seems pretty tight, I take it off and reinstall it, and the problem is solved.

 

[Donut707]

At lunch i was able to verify the battery terminals were tight . On my drive over to m shop it finally threw a dtc PO537 brake switch stuck on ... when i hooked up the matco scanner , it read the P0573 brake switch and a pending P0501 vehicle speed sensor 1 performance. we inspected the wheel speed wiring and sensors , looked for obvious sign of any other wiring issue and couldnt find anything. I cleared the codes and the jeep drove fine back to work ... so i will continue to monitor / thanks for all the input ..

 

[Disciple Off Road]

I’m still gonna say loose battery as stated. They will actually feel tight by hand but the OEM terminals suck. And a faulty ground can throw some random codes for sure. Seeing the tac drop like it is and lights flashing all crazy screems ground wire. Ive had the same issue. A faulty sensor will just throw a code or the traction control light on the dash.