Bleeding question

[fjray]

I'm thinking while the tricycle is on the lift, I might as well flush the brakes. Reading the manual it says front calipers, rear caliper and the VCM. It also says the budds needs to be used. What is the VCM and why can't it be bled like other bikes with ABS??. I've bled tons of brakes but living a long way from a good dealer and in the middle of winter I don't want issues. Thanks

[Chupaca]

you can do it just normally but there is the nanny controled section that has to be activated with the buds system. Many just bleed and bypass that section you just do the RF, LF and Rear. Now to fully flush the system you need buds. I think the regular flush is good enough when done at least once a year....

[fjray]

That is kind of what I thought. Mine was built in April of 15 so It's due . I'll pick up some fresh fluid and give it hell.

Love you avatar pic. I've had Bassets for years.

[Bob Denman]

I'm glad that this wasn't another thread about how I can't even pop the seat open, without tearing some knuckle-hide loose!



Seriously: good luck with the project!

[fjray]

Just finished up. Hard to believe that stuff was only two years old. Came out damn near black. I flushed a couple bottles of fresh through it. Still need to do My hand brake but it's only a year old so I'll wait until the next oil change while the plastic is off that side.

[Bob Denman]

Did you take it out for a test-run yet?
(Since the use of BUDS seems to be talked about so much: I'm curious as to whether or not your bike threw any codes...)

[fjray]

Did you take it out for a test-run yet?
(Since the use of BUDS seems to be talked about so much: I'm curious as to whether or not your bike threw any codes...)

I've got nothing but snow and ice as far as the eye can see. It will be a couple months before I can test it. I did start it and go the length of my shop a couple times and it still stops so I didn't totally screw it up. The shop is about 50' long.

[Bob Denman]

Then it's a case of:
"So far: so good!"

[SNOOPY]

you can do it just normally but there is the nanny controled section that has to be activated with the buds system. Many just bleed and bypass that section you just do the RF, LF and Rear. Now to fully flush the system you need buds. I think the regular flush is good enough when done at least once a year....

Old thread, new question.


So ive flushed/bled my brakes before and had no issues.

This time bled brakes, had good pedal. Went to change oil and when I started it to warm up I see a brake failure message.

havent driven the bike yet, just rolled it out to warm up for oil change.

Finished the oil change and when starting back up to get oil flowing and top off, didn’t see the brake message again.....but have a light pedal that I can tell.

Didnt want to press the issue, so rolled back into the garage.

Thinking to go back through the bleeding process according to the manual to get a more solid pedal.

If if I can accomplish that, then run by the dealer to have the BUDS checked for full pressure.


Think I’m missing anything? Or because I turned the bike on messed something up beyond now bleeding it?



.

[SNOOPY]

So no one bleeds brakes?

[Grandpot]

If you do not have any codes, but still have a brake warning, it is possible the low pressure switch has been activated. There are three switches in the brake circuit. 1. Brake light switch, 2. Hydraulic pressure switch, and 3. Low pressure switch (this is really a limit switch that just senses the pedal has traveled too far). This can be reset by the following procedure.


After a low pressure switch (LPS) problem has
been solved, it is necessary to clear the occurred
fault in the VCM as fo llows:
1. Turn ignition switch OFF.
2. Wait 30 seconds.
3. Turn ignition switch ON.
rmr2011-086
www.green-manuals.com
4. Firmly press brake pedal until you hear a "click"
from the LPS sw itch or until braking pressure
reaches 3 500 kPa (508 PSI) .
NOTE: The 1st click will come from the brake light
switch. Continue to strongly press pedal to hear
a 2 nd click. This one will come from the low pressure
switch. You may not hear the click, just push the pedal real hard.
NOTE: Use B.U.D.S. to monitor brake pressure if
desired.
~
5. Turn ignition switch OFF.
6. Wait 30 seconds.
7. Turn ignition switch ON.
8. Validate fault was cleared.

[SNOOPY]

Cool!

Thank you!

Going to re bleed using the procedure in the manual this time lol

Then will try this to make sure the code gets cleared.

If local dealer can hook to BUDS and validate things within a couple hours, will do that.



.

[IdahoMtnSpyder]

Cool!

Thank you!

Going to re bleed using the procedure in the manual this time lol

Then will try this to make sure the code gets cleared.

If local dealer can hook to BUDS and validate things within a couple hours, will do that.



.

It was a couple of weeks, I think, after I bled my rear brake before I got it to the dealer for the BUDS check. All seemed to be working OK so didn't I didn't worry too much about it. There is the EBD, electronic brake distribution, controller in the system that nanny controls. It controls the braking force distribution between the front wheels and rear wheel. If it's not working correctly the manual says you could lock up the rear wheel in hard braking. I figure that to make absolutely sure the braking system works properly it really is a good idea to have the BUDS check.

[jstjohnz]

There are three switches in the brake circuit. 1. Brake light switch, 2. Hydraulic pressure switch, and 3. Low pressure switch (this is really a limit switch that just senses the pedal has traveled too far). This can be reset by the following procedure.


After a low pressure switch (LPS) problem has
been solved, it is necessary to clear the occurred
fault in the VCM as fo llows:

Thanks for the very good info, but I'm having trouble understanding the operation of the Low Pressure Switch. It apparently opens (or closes) when brake line pressure reaches about 500 psi. Normal braking presumably doesn't reach this pressure, but a hard press on the brake pedal should.

How does the switch detect a problem if it doesn't know how hard the pedal is being pressed (or how far) when it operates?

Clearing the fault sounds like you're basically saying, "see, if I press the pedal hard I can reach 500 PSI", but what happens to SET the fault condition in the first place?

And why do you need a switch to sense the 500 PSI threshhold when the pressure switch (actually this is an analog pressure sensor that reads actual pressure) could do the same thing?

Or is the low pressure switch in a different point in the hydraulic system than the pressure sensor?

[jstjohnz]

OK, I think I found the answer to my question in another thread. Apparently the low pressure switch is not actually monitoring pressure at all, it is monitoring brake pedal travel. It activates when the brake pedal reaches something near full travel.

If, when this switch activates, the brake system pressure is less than about 500 PSI, that tells the computer that the brake system is not generating the pressure that it should be generating at that point of pedal travel.

So the 3 switches (2 switches and a pressure sensor, ) do:

Brake Light switch, activates at beginning of pedal travel to tell the computers that you are braking and activates brake lights.

Brake Pressure Sensor monitors actual pressure in the hydraulic system.

Brake pedal travel switch indicates brake pedal has been depressed nearly to the normal full down position.

I think.

[IdahoMtnSpyder]

OK, I think I found the answer to my question in another thread. Apparently the low pressure switch is not actually monitoring pressure at all, it is monitoring brake pedal travel. It activates when the brake pedal reaches something near full travel.

If, when this switch activates, the brake system pressure is less than about 500 PSI, that tells the computer that the brake system is not generating the pressure that it should be generating at that point of pedal travel.

So the 3 switches (2 switches and a pressure sensor, ) do:

Brake Light switch, activates at beginning of pedal travel to tell the computers that you are braking and activates brake lights.

Brake Pressure Sensor monitors actual pressure in the hydraulic system.

Brake pedal travel switch indicates brake pedal has been depressed nearly to the normal full down position.

I think.

Based on a quick review of the service manual I'd say you've got it pretty well figured out.

[Grandpot]

OK, I think I found the answer to my question in another thread. Apparently the low pressure switch is not actually monitoring pressure at all, it is monitoring brake pedal travel. It activates when the brake pedal reaches something near full travel.

If, when this switch activates, the brake system pressure is less than about 500 PSI, that tells the computer that the brake system is not generating the pressure that it should be generating at that point of pedal travel.

So the 3 switches (2 switches and a pressure sensor, ) do:

Brake Light switch, activates at beginning of pedal travel to tell the computers that you are braking and activates brake lights.

Brake Pressure Sensor monitors actual pressure in the hydraulic system.

Brake pedal travel switch indicates brake pedal has been depressed nearly to the normal full down position.

I think.

Yes, that's it.

What caused the condition in the first place? This has happened to me a couple of times. When the parking brake is ON and your foot is on the brake pedal, then you release the parking brake, you will feel the brake pedal go down an additional amount. If it goes down far enough to activate the 3rd switch, that is when you get the brake failure message. Now I'm just careful of the pressure I put on the brake pedal when I release the parking brake. No more problems.

[SNOOPY]

Good points, thanks.

[Bob Denman]

Where have you been hiding?