ABS light stays on
Cruiser
Joined: Nov 2011
Posts: 138
Likes: 2
From: Small Country
I just wish everybody was posting the electrical-related questions in one section only, it is pain in the butt going through all the topics to find people looking for help in troubleshooting for electrical problems, this site is way too slow .
Cruiser
Joined: Nov 2011
Posts: 138
Likes: 2
From: Small Country
I would suggest trying to disconnect both switches, then going for a ride to see if cruise control still works. If it does still work and doesn't deactivate until the clutch is pulled in or the throttle is rolled forward, then it really is a lawsuit waiting to happen and violates many safe practices in terms of vehicle operation and consumer safety..
Cruise Control has been around for more than 20 years. Most cars were using mechanical brake switches with no diagnostics up to my knowledge no body has been sued for that?
Many modern cars use Hall-affect sensors for Brake Switch. Those sensors still have two legitimate states Closed and Open.
- There are many type of failures which can cause even a Hall Effect switch to appear in legitimate state ( and no fault can be diagnosed).
- Since the Hall-Effect sensors rely on constant gap between the pedal (brake lever) and the sensor if the linkage develops a slop the sensor output will appear as Open Switch legitimate state.
- There is no electronic module that I know of that can positively know if the brake pedal is really applied or no. And just by looking at the Brake Switch Inputs no module can be 100% sure if brake is applied or not.
- On cars with Automatic transmissions where it is required to have the brake applied in order to shift into gear if the module does not see Brake applied (switch closed) it will not go into cruise either. But on cars with manual transmission brake application is not required, so if the Brake switch is Open it is perfectly legitimate state, and the car can later go into Cruise.
- As I mentioned earlier, it is the multiple redundancy that actually provides the Cruise function with sure way to get out of cruise when necessary and to prevent safety hazards to the operator.
- No company looks down on the safety. Each company has a big Product Liability department and all they do is looking for any gaps in the safety of the vehicle. The Cruise Control mechanization I described above has been standard for the industry for many years, nobody got sued over it.
Then again, there was a guy who used his lawnmower as a hedge trimmer and got his fingers cut the jury of 12 wise men awarded him compensation for his ingenuity. Everything is possible around here; you may try your luck as well.
Well, thats my little knowledge on the subject. Arguing gets me tired, besides Im not a missionary who is trying to convert somebody to accept his beliefs.
I would gladly admit that Im wrong if you could just list the cars which have 100% diagnostics of the Brake Switch together with their software algorithms for Cruise Control operation. Even better which bike you know that has full brake switch diagnostics? What brake switches they use, how the Cruise Control software operates? Besides Harley Ive had Suzuki and Honda, Ill be glad to sue them as well since their cruise operates just like the Harley one, even worse does not have that much redundancy. J)
Lawyers would be lining up around the block to take a case where you hit somebody because the cruise control was active and the brake switch didn't cancel it. If you've only lightly used the brakes and it has no idea the brakes were tapped it's going to keep adding throttle to maintain vehicle speed...
If you only lightly used the brakes you are going to hit somebody anyways, regardless of cruise.
Besides, regardless of brake switches and cruise when you apply brakes your vehicle slows down anyways- brake switch malfunction does not constitute brake system malfunction.
With Cruise the hazardous situation is when you applied brakes and expected the cruise to shut off, but then you released brake and vehicle accelerated unexpectedly. This is when you have to apply brake again, or roll the throttle off, or pull the clutch in, or downshift. Which people do instinctively anyways, with rare exceptions like the guy with the lawn mower people like him are prime candidates for the Darwin Award. As I mentioned earlier, if you brake seriously (not tapping the brakes) the Cruise will turn off anyways when detects sudden speed change.
Nothing is perfect in this world, even the space shuttle fails every now and then, though it costs gazillions of dollars
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
You guys are right in saying that something has to float in a disc brake system. Something has to have the ability to move to compensate for pad/rotor wear and manufacturing tolerances. But it doesn't always have to be the caliper or the rotor. Where the necessary "float" is actually present in the HD/Brembo system is not the caliper or the rotor, as each is fixed, but the brake pads within the caliper. Each pad has its own piston(s) and those pistons/pads can float side to side. This is how the necessary float is incorporated into our bikes.
Aborigen2 - Welcome aboard! It's nice to have someone with your knowledge of electronics on board. Electronics is one of my weaknesses.
Aborigen2 - Welcome aboard! It's nice to have someone with your knowledge of electronics on board. Electronics is one of my weaknesses.
The brake piston cleaning during pad replacement is important because they can get cockeyed with the pad dust keeping them from going back to where they need to be for new full thickness pads as there is no other float in the system to center the pads.
Road Warrior
Joined: Aug 2010
Posts: 1,268
Likes: 8
From: Detroit, the asshole of America
Cruise control has been on vehicles for 40+ years, not 20. My '67 Imperial had cruise control, and it wasn't the first vehicle to be equipped with it.
Every Ford and Chrysler vehicle, as an example, currently produced and sold to the public has MULTIPLE brake switch diagnostics. There are signal checks and plausibility checks.
I can and do calibrate diagnostics for hall effect sensors for a major auto manufacturer, among other things. Any sensor can be diagnosed. If it cannot be diagnosed, it cannot be installed on the vehicle as it will not be able to be sold to the public with an input unable to be diagnosed. How would you troubleshoot a vehicle with a nonfunctional sensor, yet there weren't any diagnostics for it?
Go try it (unplugging both brake sensors) and see for yourself. If it doesn't work as intended, somebody phone Sam Bernstein and get rich.
Every Ford and Chrysler vehicle, as an example, currently produced and sold to the public has MULTIPLE brake switch diagnostics. There are signal checks and plausibility checks.
I can and do calibrate diagnostics for hall effect sensors for a major auto manufacturer, among other things. Any sensor can be diagnosed. If it cannot be diagnosed, it cannot be installed on the vehicle as it will not be able to be sold to the public with an input unable to be diagnosed. How would you troubleshoot a vehicle with a nonfunctional sensor, yet there weren't any diagnostics for it?
Go try it (unplugging both brake sensors) and see for yourself. If it doesn't work as intended, somebody phone Sam Bernstein and get rich.
Cruiser
Joined: Nov 2011
Posts: 138
Likes: 2
From: Small Country
40 years is more than 20, isnt it? Or you just want to shine with knowledge of history? J)
You really can diagnose ANY Hall-Effect Sensor 100%? Well, I cant. Though I also know a little bit about Hall-Effect sensors. Unless you are using 3D or Rotary Sensors for brakes?
The signal usually is based on target present and target not present voltage or resistance to GND how can you tell in advance if the target will ever be present? What if due to play in the linkage the gap has increased?
Also, what you are measuring to determine the connections to the sensor are intact is the output interface of the sensor there are failure modes where that output can fail stuck within the legitimate voltage range.
You do that Ill be glad for you if you can get some easy money! J)
I think you are over exaggerating the importance of the brake switches. Yes, on cars with automatic transmissions it is somewhat important. But what you forget is:
- Bikes have two brakes. Both switches are independent. Any switch activation gets you out of cruise. Failure of both switches within the same trip is less likely than winning the lottery.
- Cruse and Brake system are independent. Regardless of Cruise ON, if you apply brake the vehicle will slow down.
- If your brakes are working, and you hit somebody thats your fault for not using the brakes; cruise ON will not help you.
- Lets say you applied brakes but cruise did not disengage? Whats going to happen?
- When you release brakes the vehicle will start accelerating trying to reach the pre-set speed.
- BUT! Here is the catch: Vehicle speed can not increase by more than 0.5mile/sec!!! (this is a control algorithm embedded in the ECM). Leave alone that it is Harley and will not jump forward like a wild bronco.
- so, with 0.5 mile/sec speed increase what is going to happen?
For reference only:
- The reaction time of a normal person is 0.2 sec he will react right away when vehicle does not slow down (see redundancy)
- The reaction time of an asleep at the wheel man can be up to 3.0 sec. In that time vehicle speed can increase only by 6 mph doesnt seem like a runaway or possessed vehicle, does it?
Talking about failure of Cruise to disengage on bikes I can give you examples where the vehicle kept running at the cruise speed not because the ECM did not turn off the cruise, but due to mechanical failure in the throttle linkage kinked cruise cable sticking in the sleeve, for example. Things like that could happen on non-TBW vehicles. Nevertheless, your brakes are always with you, no Cruise can prevent you from stopping safely.
Thread Starter
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Intermediate
Joined: Mar 2008
Posts: 38
Likes: 0
From:
I put on over 100 miles today running errands and the light stayed off once I started moving. It seems that I did something to clear up this problem when I replaced the front pads. Interesting....
Stage III
Joined: Mar 2010
Posts: 3
Likes: 0
From: Central Florida
ABS light stays on
I"m new to this forum, and have decided that I need some guidance!d I have an '09 Ultra and the ABS light stays lit. I've checked the wiring from the ECU to the Tach, and the ECM all resistance readings and voltages are within proper operating range. During the diagnostic check, it states that there is no response from the system. Would an open circuit in one of the wheel sensors cause this to happen.....any thoughts?
I hope that I've posted this in the right spot, and that I haven't over looked the answer somewhere else.
I hope that I've posted this in the right spot, and that I haven't over looked the answer somewhere else.
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Intermediate
Joined: May 2010
Posts: 26
Likes: 1
From: North Carolina
ABS Problem
I have the same problem with my Ultra. If I go backwards with the ignition on the light stays on. This is my second time with this problem. First time was under warranty. I did not ask the dealer what he did to fix it. Right now I just wait till I am ready to forward before I turn on the ignition.
Road Master
Joined: Sep 2009
Posts: 761
Likes: 9
From: lewisville, nc
With it running idle...do some full lock turns on the bars. If that light comes on then its the speed sensor wires getting folded over both ways at the plug behind the neck by the main harness.