Thread: fault code reset needed after Option B?

Originally Posted by Roverlord off road spares

Got a love hate relationship with my Landy

Maaaaattttteeee I know that feeling
Its like having 2 heads/minds

Its good/Its crap, Its good/Its crap....................... Mmmmm starting to hear voices

Last resort for those who still suffer the 3 Amigos,presuming you have done all the usual fixes,consider the hubs.
Very little end float or runout will effect the sensor reading and could trigger a fault.
so presuming you have fixed modulator, checked earths etc and replaced sensors and still have issues,maybe the hub next.
A Nanocom may show it as a sensor fault but I think the T4 actually has the ability to detect a "hub excessive clearance" issue.Not much help unless you have one,but if you are still getting a sensor fault maybe that hub is the issue.

Trev.

Alex just left without any lights on!

Checked faults and had intermittent sensor fault, front left. Cleared, lights stayed on. Ran Nanocom through whole system and couldn't clear lights. Ran ABS pump tests on each corner then a modulator bleed and hey presto. Not sure but looks like it may have had some air in the system from correcting a twisted hose.

Can anyone confirm what is involved in a modulator bleed and if any air in the hose would have worked it's way up (not likely I'd have thought from experience) and caused the issues in the modulator and lights?

Maybe the info you want is in here somewhere

http://www.aulro.com/afvb/discovery-...r-bleed-2.html

Copied from http://www.aulro.com/afvb/discovery-...wer-bleed.html for reference & future searching purposes.

Thanks to Paul (Offtrack) for the material.

As noted the tests must be done with the ignition off, I think this is forced as at least I think my Nanocom doesn't communicate with the ignition on.

Wabco ABS: Manual Bleed Procedure with Electronic Control
Equipment

This is the WABCO procedure for bleeding a dry ABS braking system. This looks close to the Nanocom modulator bleed information and to LMR's advice so should provide a basis for a usable procedure. The Wabco wet module bleed is essentially the same as the manual bleed procedure in RAVE.

Quote:
Manual Bleed Procedure with Electronic Control Equipment

NOTE: The electronic control equipment must be capable of actuating (energising) the outlet solenoid valves for each wheel for approximately 10 seconds and activating the pump of the modulator. The inlet solenoid valve should be open (de-energised). The Meritor WABCO Diagnostic Controller can be used to do this.

1. Apply the parking brake and chock the tires. Turn the ignition OFF.

NOTE: The ignition must remain off for the initial bleed procedure; energising the unit during bleeding must be impossible.

2. Perform brake bleed procedure for wet module, bleeding the circuit and master cylinder if required prior to connecting electronic control equipment. Use Pressure Bleed Method if equipment is available; if not, use the Manual Bleed Method.

3. Install electronic control equipment to ECU, or to the modulator assembly and pump.

4. Turn ignition switch ON or power electronic control equipment.

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

6. Activate the pulse function on the electronic control equipment starting with the longest brake circuit, typically the rear.

7. Release brake pedal for 5 seconds and activate the pump of the modulator 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)” on page 14.


10. Repeat Steps 5 through 9 for the remaining 2 [sic] brake actuators.

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.).
So it would seem the whole process using Nanocom is something along the lines of:

1. Manual Bleed all wheels with ignition off (or Nanocom Power Bleed?)

2. Following RAVE bleed sequence (PF, DF, PR, DR) on each wheel
- run Nanocom ABS Modulator Bleed routine with pedal fully depressed, release pedal, repeat process 4 times
- bleed manually (or Nanocom Power Bleed?)
- move to next wheel in sequence

cheers
Paul

For completeness this is the Wabco wet bleed procedure:

Quote:
Manual Bleed Procedure (Wet Modulator Assembly)
1. Apply the parking brake and chock the tires. Turn the ignition OFF and disconnect the battery terminals.
NOTE: The ignition must remain off for the entire bleed procedure; energizing the unit during bleeding must be impossible.
2. Fill the reservoir with DOT-approved hydraulic brake fluid.
3. Depress the brake pedal five times using the stroke between 1/3 travel and maximum travel in 5 seconds.
4. Release the pedal for 5 to 10 seconds. Air bubbles will rise into the reservoir while depressing and releasing pedal.
5. Repeat Steps 3 and 4 another three times, or until sufficient pedal resistance is felt.

6. Bleed the brake system. Put a wrench on the brake actuator bleeder fitting. Start with the farthest from the modulator, (typically the right rear), then attach a length of clear plastic tubing to the bleeder fitting. Make sure the tube fits snugly.
7. Submerge the tubing in a container of clean brake fluid. Figure 7.
NOTE: Both the tubing and container must be able to withstand to the effects of brake fluid.
8. Depress the brake pedal 10 to 15 times, using the maximum available stroke.
9. Loosen the bleeder fitting until the fluid begins to flow, (about 3/4 turn), while depressing the brake pedal through its maximum available stroke.
10. Tighten the fitting firmly prior to releasing the brake pedal.
11. Repeat Steps 6 through 8 several times until the discharged fluid is free of air bubbles.
12. Repeat Steps 3 through 9 to bleed the remaining three brake actuators. Bleed in sequence of the longest to the shortest circuit from the modulator.
13. Check the travel of the brake pedal. If a firm resistance is felt the manual bleeding procedure is complete.
14. Check the fluid level in reservoir and fill if required. Replace reservoir cap and dispose of used brake fluid.
15. Remove wheel chocks