Thread: Option B Repair for Defender Fail

Get a D2 mate,mine was easy peasy to sort,plenty of working room.Will tell my boy you dont like engineers
How bad are your discs???
I let mine run out pretty badly in the D2,once I replaced all the brakes the 3 amigoes went back to Mexico,I did the shuttle valves first.
I think you will find if there is any runout in the discs they stir the sensors up.Didnt think ABS issues were as common in the TD5 deefers.
GOODLUCK
Andrew

Andy,
Discs are in good nic, though do squeal.
I think I may have stuffed up a little with the wiring, was led to believe the Yellow Grey wire on the Defender was the equivalent to the Yellow Green wire on the D2. A bit of investigation shows that the Red Black wire on a Defender is equivalent to the Yellow Green, so will do some mods tommorow and see if that works, if not back to square one and then maybe some new disc rotors when i have the spare cash. And maybe a new SVS.
Lucky it is due for brake fluid change.
Cheers
Craig

Hi Craig

Is why I like my 130, no ABS, central locking etc. nice and simple.

Does have other problems like clutch master cylinder, just had Wellstead Autos fit a new one for me, I hate anything to do with the pedal box!

Good luck with your problem.
Cheers

Graham

Well I think maybe a new SVS and start again with the mod as the red black wire and no different.

Did you masure the resistances of the SVS pack as in the tutorial?...cos if the resistances are within limits and you've made the mod well but you still get the SVS failure fault code then the problem is not there but on the input circuit to the ABS ECU ... i'll try to get a defender circuit diaram to confirm if that wire colour is the proper one or not

The microswitch area should be dry. Indicates an oring failure of the pistons.

I dont think it was an o ring failure. Just appears to be a lot of crap build up as in the Defender very poor location where water and gunk can build up underneath and get into the SVS unit as it pretty much sits flat on the firewall / guard. Was full of dirt gunk, but the switches looked ok, but may be corroded on the board. Resistance was not in spec either before of after mod. There was resistance just not that shown.
I had to put back in as I may need the car, so will just be with lights on and no ABS.
Will finish bleeding the brakes today and see if any difference.

I have the Rave wiring diagrams and comparing to the D2 Yellow Green wire seems to line up with the Defender Red Black wire. If anyone else can confirm it would be appreciated. Cannot find much on the mod for a Defender other than the same mod has been done but no wiring confirmation.

I will probably order a new SVS tonight and replace next break and maybe the o rings if they can be replaced.

The Defender layout is a nightmare, however I have now nutted it out. You are going to make a bit of a mess. The following is the way I have worked it out to be best.
1: Suction out brake fluid reservoir. I used a syringe and 19 gauge needle that allows you to get right into the master cylinder.
2: Remove bracket holding pipes on the end of the clutch master cylinder box.
3: Remove 3 plugs 2 on modulator and 1 on brake booster. Alos remove second section of plug on brake booster (nut).
4: Undo modulator output pipes one at a time. You will get some fluid seep out and use syringe and needle to empty. You will only get a couple of ml at a time and you may need to do 5 or 6 times to empty. You still wont get it all and when you continue can still make a mess.
5: Cap all outlets.
6: Remove inlet pipes at back of modulator. Some fluid may come out. Use rag to clean. Very difficult to get hands in.
7: You may need to tie back pipes so they do not get caught on modulator.
8: Next will depend on whether you are just going to remove the whole modulator or just remove the SVS.
9: Undo and remove the front rubber mount.
10: I did not undo the back ones but just pulled forward pulling the rubber block out of the seat. Near impossible to get your hands to these to actually undo the nuts and remove the whole mounts. A good pull will dislodge. Remove rubber mounts off modulator.
11: Now the fun starts as the modulator will not just lift out. It misses by about 10 mm at the front. You need to rotate the unit until you can basically turn it over, may have to rotate sideways as well. The first time I took out in one piece. However I found that if you can get upside down, remove the SVS and it is easier to remove, but you still will need to get sideways so it will come out of the space. You May also still make a bit of a mess with fluid. I keep degreaser on hand at this point and degrease. If you have not capped the fluid inlets outlets I would remove and then degrease. You can then see the issue with the mount and how crud can build up just behind and underneath the SVS. I will probably seal the SVS when I replace.
12: Reverse procedure when replacing. If modulator out. Leave off SVS. Put in mod, going to be some stuffing around to get in position.
13: Fit SVS. Rotate to right way up.
14: Once upright refit rear rubber mounts and slide into mounts, easy for rubbers to be knocked out.
15: Fit front mount.
18: Fit pipes
19: Fit plugs x 3.
20: If doing option B wire into main harness plug will need to be spliced before square plug is replace. Earth out wire.
21: Fill and bleed brakes.

Originally Posted by clubagreenie

The microswitch area should be dry. Indicates an oring failure of the pistons.

Not sure this occurred, the problem is with a Defender you are going to get fluid run out of the modulator and down into the SVS. Maybe an o ring failure, may not. It did not seem too wet as such, but there was a build up of crud in the unit, so maybe corroded switches internally.
I think the easiest way is to start again with new SVS and maybe o rings.
Cheers
Craig