Thread: Hill Desent

SLABS - UTILITY

It's on the second screen in the slabs module. There is a scroll bar at the bottom of the first screen, you need to click the right arrow.

I found it, and no I did not do this when I bled brakes.



Can anyone explain what these features do.

I pressed "POWER BLEED" and the pump did one pulse. I then pressed "MODULATOR BLEED" and the pump did about 10 pulses. I then pressed "FRONT RIGHT TEST" and again it ran the pump for about 10 pulses. What is it testing?

I have been driving for about a week now. The brakes are fine and after doing the above made no difference.

Originally Posted by Mr Whippy

Can anyone explain what these features do.

I pressed "POWER BLEED" and the pump did one pulse. I then pressed "MODULATOR BLEED" and the pump did about 10 pulses. I then pressed "FRONT RIGHT TEST" and again it ran the pump for about 10 pulses. What is it testing?

I have been driving for about a week now. The brakes are fine and after doing the above made no difference.

[ame="http://www.youtube.com/watch?v=oOfoYn6TaCU"]Nanocom Bleed Functions - YouTube[/ame]

"Power Bleed" runs the abs return pump for a couple of seconds.
"Modulator Bleed" pulses the modulator solenoids and return pump for about 5 seconds.

Both these functions are reverse engineered versions of the routines that the Testbook system provides for bleeding the D2 ABS.

Running them on their own will make no difference to brake feel.

3. Connect diagnostic equipment to OBDII port.

4. Turn ignition switch ON

5. Push on brake pedal with maximum force (firm
pedal) and hold.

6. Activate the "Modulator Bleed" function on the diagnostic tool
starting with Passenger Front. (Note: you may be able to use the "test" function for each wheel for this step)

7. Release brake pedal for 5 seconds and run the Power Bleed function
for approximately 5 seconds.

8. Repeat Steps 5 through 7 three additional
times.

9. Perform manual bleed on appropriate wheels.

NOTE: To perform a manual bleed, follow
Steps 2 through 8 under “Manual Bleed
Procedure (Wet Modulator Assembly)”
10. Repeat Steps 5 through 9 for the remaining 3
brake actuators, working in order of Drivers Front, Passenger Rear, Drivers Rear.
NOTE: If a firm brake pedal resistance is felt and
the brake pedal pushes back when the solenoids
and pump are simultaneously actuated for each
brake circuit, the system bleed procedure is
complete. If there is no firm pedal resistance,
repeat the bleed procedure and/or look into brake
system defect, (leaks, etc.).

The repeated modulator/power bleed cycles followed by manual bleed ensures that any air trapped in the ABS Modulator and braking system is forced to the calipers where it can be bled out.

FRONT RIGHT TEST - FRONT LEFT TEST - REAR RIGHT TEST - REAR LEFT TEST
This function activates the modulation of the brake on the desired wheel. During the function if you turn the wheel by hand, you can see that it is blocked several times for few seconds.

I'd hazard a guess that you could use this to bleed or test pedal feel on individual circuits, not just by spinning the wheel.

cheers
Paul

Hey all,

I just changed brake lines all around, new pads and 2 new calipers in the rear on my Discovery 2 2003 TD5. I cleaned everything and drained the front calipers from brake oil. Now I had the perfect opportunity to use the "power bleed" function on my Nanocom.

I did it in the order RAVE suggest (shortest line first) ie. the opposite to "normal" brake bleeding. There are different suggestions here ont the forums but I guess RAVE must have some thoughts in its procedure.

Opened caliper front left (Its a left hand car), put a hose from the bleed screw to a bottle and turned on the power bleed.. Again, again and again. After 15 times fluid started to pour. I actually pressed the pedal a few times in between. When no bubbles, next wheel FR. The fluid came after 2 or 3 runs. It had a lot of bubbles. I pressed the button about 10 times more and moved to RL. This was a new caliper but the fluid came pretty quick and almost no bubbles. Then RR and that also went quick and almost no bubbles. I pressed the brake pedal a few times in between.

Then I did the modulator bleed 2 times with the pedal pressed hard. I did not let the modulator get any air during the brake change but you never know. I bled the system all around one more time. The bubbles were mostly from the front (right side?) and almost nothing from the rear.

The brakes are good now but the pedal is not super hard when running the car. Should it be? Its stone hard when the car is off. The automatic brakes works in low range.

I used about 1L of fluid in total. Maybe I should have drained more?

Just a thought, because of all the bubbles from the front, could that be the reason why RAVE suggest that you should start with the shortest line first? To get out the bubbles as much as possible so it wont wander to the rear?

I topped of the brake oil after 4-5 power bleeds the whole time.

Take care,
Carl

The pedal will always be hard when the engine is off as there is no vacuum assistance. If there is air in the system the pedal will not be hard. It should not be super hard with engine running.

If the booster is working as it appears to be, the peal will always have a bit of a spongy feel, especially when comparing to engine off pedal.

When I did mine I just judged the pedal on it being the same as it was before I started working on it.

If HD and TC all work and it stops well without pedal going too far down, I would say that all is good.

Originally Posted by d2dave

The pedal will always be hard when the engine is off as there is no vacuum assistance. If there is air in the system the pedal will not be hard. It should not be super hard with engine running.

If the booster is working as it appears to be, the peal will always have a bit of a spongy feel, especially when comparing to engine off pedal.

When I did mine I just judged the pedal on it being the same as it was before I started working on it.

If HD and TC all work and it stops well without pedal going too far down, I would say that all is good.

Thanks! I will go out for a drive tomorrow and do some more testing..

/Carl

Yeah, if pedal sinks with engine start your booster is working. These vehicles just have crappy pedal feel, sadly.