P38 new problem with abs and traction fault

[maxderby]

Hi all thanks once again, what's the procedure for bleeding the abs pump? All sensors are good and now down to just abs light on

 

[Datatek]

Hi all thanks once again, what's the procedure for bleeding the abs pump? All sensors are good and now down to just abs light on

There is no specific procedure for bleeding the pump, you bleed the brakes per the instructions in RAVE. How do you know the sensors are good?

 

[maxderby]

hi
tested the sensors as informed in this thread, cant remember exact readings but they did pass to the figures given, suppose i could test them again, some how 4.9v or 4.9 ohms stick in my head, could be wrong

cheers
glyn

 

[FEI]

The pump bleeding is part of the whole brake system bleeding procedure. There are two bleed nipples on the side of the valve body, the one does the pump and the other does the master cylinder if i remember correctly.

 

[Datatek]

The pump bleeding is part of the whole brake system bleeding procedure. There are two bleed nipples on the side of the valve body, the one does the pump and the other does the master cylinder if i remember correctly.

There are 3 bleed nipples on the master cylinder, one is hidden on RHD vehicles under the foam.

 

[pwood999]

3, 13 & 15 in the picture below:

 

[MontyChambers]

Mark was first!

Thank you Mark

 

[MontyChambers]

New bulb fitted, brakes bled,
ABS-TC lights still on!
WABCO D OUTPUT SETTINGS?

 

[Mark Piercy]

New bulb fitted, brakes bled,
ABS-TC lights still on!
WABCO D OUTPUT SETTINGS?

Have you driven it to clear the abs light from startup

 

[MontyChambers]

Just took it for a spin and still have the ABS TC lights on!
I had my nanocom going? not sure what to make of it?
brakes feel good.

 

[pwood999]

Nanocom recordings are "usually" in the same order as the screens, i.e. the first four columns are Sensor Voltage, and then columns 5-8 are the Wheel Speeds. Values 9-12 are Inlet Valves, and 13-16 the Outlet Valves.

I thought the two brake switch contacts should be opposite, i.e. one is open when the other is closed ? Your recording shows them as closed or open together, but occaisionally with the inverted status they should have ? This could be a Nanocom recording effect, but check the brake switch just in case.

 

[MontyChambers]

I can tick off the ABS sensors as good,
The bulb is new
I should begin looking at a wiring fault, the wiring all looks tip top though, this truck has been kept well.

 

[MontyChambers]

Nanocom recordings are "usually" in the same order as the screens, i.e. the first four columns are Sensor Voltage, and then columns 5-8 are the Wheel Speeds. Values 9-12 are Inlet Valves, and 13-16 the Outlet Valves.

I thought the two brake switch contacts should be opposite, i.e. one is open when the other is closed ? Your recording shows them as closed or open together, but occaisionally with the inverted status they should have ? This could be a Nanocom recording effect, but check the brake switch just in case.

Where are the brake switches to be found? Near the pedal presumably?

 

[pwood999]

Check the brake switch using Nanocom. No need to drive around for this. Here's my Wabco-C but the brake switch wiring is the same. Switch-1 should be normally closed, and open when the pedal is pressed. Switch-2 closes when pressing the pedal.

You will see a slight delay in the Nanocom screen . . . . .because it's a slow old design !!

Brake Off	Brake On

 

[MontyChambers]

Just a side question, my nanocm has stopped working properly, I want install firmware but it asks for a numeric code. Where can I find that code?

 

[MontyChambers]

Just a side question, my nanocm has stopped working properly, I want install firmware but it asks for a numeric code. Where can I find that code

 

[Datatek]

Just a side question, my nanocm has stopped working properly, I want install firmware but it asks for a numeric code. Where can I find that code

Try the support forum at Blackbox Solutions.

 

[MontyChambers]

Yes, thanks, I am on that now!

 

[MontyChambers]

Check the brake switch using Nanocom. No need to drive around for this. Here's my Wabco-C but the brake switch wiring is the same. Switch-1 should be normally closed, and open when the pedal is pressed. Switch-2 closes when pressing the pedal.

You will see a slight delay in the Nanocom screen . . . . .because it's a slow old design !!

Brake Off	Brake On
View attachment 341393	View attachment 341394

But how do I change the setting for brake switch 2?

 

[pwood999]

You can't change the setting because it's an input. The switch on the pedal frame has two contacts in it. Onbe is normall closed & the other normally open. Therefore both toggle on Inputs screen on the Nanocom when you press the pedal.