A friend of mine has had an intermittent issue with faulty ABS sensor code coming up on his 2002 LS430. Looking for ideas on where to go next to troubleshoot.

Intermittent error code produces the usual cluster of warning lights, and the ABS system turns off. The error code when read is Left Front Wheel Sensor.

He has replaced the wheel sensor a couple of times. The wiring harness tests positive for continuity so he hasn't replaced any part of the harness.

Recently, he installed a new ABS ECU trying to eliminate the problem. No success - same error code and warning lights still come on intermittently and for no consistent reason or set of circumstances.

My shot in the dark was maybe the engine control module ECM has some issue - weak or bad solder have been known to cause transmission fault codes and other issues - but just wild uneducated guess.

Anyone have any ideas or direct experience with this issue?

 

Need to look at live data as you drive, score if the problem happens when looking at the waveform. You should see an erratic signal if the sensor/wiring is bad if it still looks perfect it probably means the computer is flaky. But unfortunately there are variations of this either way if you at least verify the signal is good then you can go from there.

 

I had the full wiring for this gen but can't find it so I'm not much help.
If you can get full wiring there may be a bad or flaky harness junction connection from the sensor to the destination that can be a problem.
The TIS color schematics are best for this as opposed to the generic overall wiring diagram because of the detail on the harness junctions.

 

This thread might help, it sounds like your sensor harness is on its way out. https://www.clublexus.com/forums/ls-...s-problem.html

 

Thanks for the tips and replies so far. Much appreciated.

 

What code is it showing? ABS codes are very specific in these systems and that will eliminate a lot of guess work. Failing wheel bearings and damaged/loose tone rings can give sensor failure codes as well.