How reliable are these ABS modules/units
I have an ABS light issue, that has gone from the ABS light illuminating when rolling past 10 mph coming on, to coming on straight away with ignition on
Dealer reckons my ABS unit has failed as they reckon the ECM is not talking to the ABS module. I don't have much faith in the dealer, as i feel, they may have instigated the ABS light and ABS failure issue, a while back when they changed the wheels from stock to slightly larger profile..
I still here the clicking noise when i apply the front brake. Bike rides good
Hence, i thought i would throw the question out there, in case there may be a cheaper fix than just going for a replacement by default.

Thanks R

 

I would check to see if there are any codes first, if not try a reset disconnect negative battery cable for about half hour and then re-connect. See if light goes away, the other thing is to bleed system with new fluid had this happen to me and after light disappeared. Fluid should be changed every two years.

 

I don't have any technical knowledge about ABS or the control modules. But I have '14 WG and the ABS light comes on with ignition then goes off as i take off riding which is part of the normal diagnostic routine. Staying on while riding though means its not engaged, and needs to be checked out which it sounds like you've done some leg work on already.
I'm assuming you read the ABS portion of the manual judging by your verbiage.
ABS lamp continuously lit -> ABS malfunction detected. See a Harley-Davidson dealer for service.
ABS lamp flashing ->This indicates a normal self-diagnostics process when the motorcycle is first turned on and the speed is under 5 km/h (3 mph). ABS is not operational until the lamp turns off. If the lamp continues flashing at speeds greater than 5 km/h (3 mph), see a Harley-Davidson dealer for service.


Best i can offer is to get another dealer/technician opinion on the issue.
It may be worth checking your brake fluid levels as well, not sure if low fluids or air in the system would cause the ABS module to alert.
Try activating the ABS on each brake individually (read not in traffic). You may only have an issue with the rear brake, try to listen for it clicking or feel for the surging/pulsing in the pedal.

 

I have a couple of thoughts:

I'm not familiar with your year of ABS but on the 2008-2011 ABS the light will flash upon start up and go out at about 5mph or so if all is well with the system. A hard ABS light (always on, not flashing) indicates fault with the system and loss of ABS function. A code should be stored in the DTC. Google how to pull those and look them up if you find any.


The things I believe you should take a hard look at:

DTC codes

Front wheel speed sensor and ALL the wiring back to the unit taking special note of the area around the sensor and the neck of the frame

Does the new wheel have an ABS bearing on the sensor side and is it facing the proper direction?

What is the measured difference (if any) in the circumference of the newly installed front wheel vs the stock one? (the front and rear wheel speed sensors compare rotation speed to work properly)

Was the ABS system working properly before the front wheel swap?


Somewhere in those points/questions ^ is the answer to your problem. I encourage you to find those answers for yourself as the dealership may not be as motivated to do so if the fault points back to them.

 

Thank you for your comments, and i am wrong, the light stays on permanently, not as i described in my OP

Front wheel speed sensor and ALL the wiring back to the unit taking special note of the area around the sensor and the neck of the frame, i am told this has been checked

ABS bearing on the sensor side and is it facing the proper direction. Verified

Was the ABS system working properly before the front wheel swap? Yes

What is the measured difference (if any) in the circumference of the newly installed front wheel vs the stock one? Wheels were changed from stock with scorchers to front 21 x 3.5 120/70-21 and back to 18 x 5.5 180/55-18, with Night Dragons.The front tire is about 1/4" greater radius from stock plus stationary, and any radial expansion difference under centripetal load. This is where i get conflicting comments, all meant well i hasten to add. Some say i need a new ABS bearing. Some say, this is what the ABS checks on self-diagnostics, so it shouldn't matter. How would the ABS manage if you get a puncture, low pressure and near flat running state.

It may be worth checking your brake fluid levels as well, not sure if low fluids or air in the system would cause the ABS module to alert. Bleed system with new fluid. Yes, i was wandering that, and it certainly needs to be ticked off

Try activating the ABS on each brake individually (read not in traffic). You may only have an issue with the rear brake, try to listen for it clicking or feel for the surging/pulsing in the pedal. when i am riding if i action the front brake, i hear a distinctive clicking sound, which i have always heard, even before the wheel change. Note this is not in an ABS state. When i operate the rear, which i don't very often, i hear nothing. But thats a normal state, not an ABS state.

try a reset disconnect negative battery cable for about half hour and then re-connect. Will look into that

 

What codes are present on the DTC ?

 

Just checked on the Powervision. No codes

 

I don’t think the powervision detects abs codes rather only engine codes.

If your abs light is on then the abs unit has air in it and needs to be bled thru a scan tool

 

Pull th DTC codes from the bike, not a tuner.

 

sorry about that

so went thru the test and got

ECM N
BCM Y, then U0121 then end
SPDO Y, then U0121 then end
ABS (nothing, no N or Y)

U0121 according to FuelMoto Trouble Code Page is Lost comm W/ABS