D2: Three Amigos On At All Times After Shuttle Valve Switch Replacement

[neuropathy]

I had the three amigos on intermittently, until I got wrench happy the other night after replacing my CPS and decided to fit the shuttle valve switch as well. Now the three amigos are always on... I followed the video guide on Atlantic British - left the ABS unit attached and just manipulated it a bit to get underneath to the SVS. I was hoping I did this correctly, but maybe I screwed up. I accidentally clicked in one of the switches while I was working with it and then clicked it a second time to try to click it out. Not sure if that matters. I found that the old SVS had one rubber seal that was either loose already or it came loose when I was removing it. There seemed to be a small amount of fluid on the switches. I’ll confirm tomorrow when I’m with the vehicle. I’ll check the pins of the old unit tomorrow for corrosion.

I read through a guide on rewiring the switch wires, but I’m not sure would make a difference in this case.

Does anyone have any ideas? I don’t have a fault reader for this, just a general one for vehicles. It was a pain getting to the SVS.

I’ll try my best but just in case, anyone know an inexpensive option to send the unit in and have it returned repaired?

 

[SGaynor]

Does anyone have any ideas? I don’t have a fault reader for this, just a general one for vehicles. It was a pain getting to the SVS.

Well, it can be a number of things, not just the shuttle valve. Without knowing the reason for the three amigos (ie, the codes), you're just groping in the dark.

Get a reader that can read the ABS codes, like this one.

Short of that, recheck all of your electrical connections.

 

[bradartigue]

I found the ABS system to require a sequence of repairs, and you absolutely need to be able to read the codes as you go.

Mine started with codes only of the shuttle valve failure, so I replaced the seals, the svs piece, and did the wire bypass. I "did it all" and bled the system, which eliminated the codes related to the modulator. Then I had codes from the hubs, so I replaced those, which come with new ABS senders. Now everything works, ABS, HDC, and TC.

If you can do it all yourself you'll save a fortune (the modulator alone shows $3,000 new at one vendor and $2,000 at another, the fix it yourself option costs about $100 and you already have $60 of that in the new shuttle valves).

It took about 2 hours to do all of this and another hour or so to bleed the brakes. I made a switch to pulse the ABS and fully bleed the system (there is a post on it under my name, pretty much two wires and a momentary switch).

 

[mlnnc]

Replacing the shuttle valve switches DOES NOTHING to address the SVS fault if the cause is the failed solder joint inside the modulator, which is the most common fault. Do the Option B bypass. It's inexpensive and not too labor intensive, and if it doesn't correct the problem you will still have performed a preventive repair for a problem that is likely to occur.

 

[JohnnoK]

It is worth a look at your earth/ground points, while you are at it.

 

[robertofollia]

My 3 amigos came 2 years ago and went, but now come on after 20 minutes of driving.
Code is the usual SVS failure.
The weird thing is they come on even when the vehicle is stationary, idling and no brake pedal depressed.
The vehicle is 23 yrs old and brake fluid has been renewed every 2 years. May be valves leaking (time to buy kit from falconworks) but I guess the switches itself are ok (will have to take them out to compare Ohms) .
I say that because, if the switches are not used because the pedal is not depressed and the vehicle is stationary no 3 amigos should light up, hence I think the fault might lie in the modulator's printed circuit. Time to strip, shave and resolder as per landroverclubvi.
Any other suggestion?
Best regards

 

[boxster]

My 3 amigos came 2 years ago and went, but now come on after 20 minutes of driving.
Code is the usual SVS failure.
The weird thing is they come on even when the vehicle is stationary, idling and no brake pedal depressed.
The vehicle is 23 yrs old and brake fluid has been renewed every 2 years. May be valves leaking (time to buy kit from falconworks) but I guess the switches itself are ok (will have to take them out to compare Ohms) .
I say that because, if the switches are not used because the pedal is not depressed and the vehicle is stationary no 3 amigos should light up, hence I think the fault might lie in the modulator's printed circuit. Time to strip, shave and resolder as per landroverclubvi.
Any other suggestion?
Best regards

My 3 amigos came 2 years ago and went, but now come on after 20 minutes of driving.
Code is the usual SVS failure.
The weird thing is they come on even when the vehicle is stationary, idling and no brake pedal depressed.
The vehicle is 23 yrs old and brake fluid has been renewed every 2 years. May be valves leaking (time to buy kit from falconworks) but I guess the switches itself are ok (will have to take them out to compare Ohms) .
I say that because, if the switches are not used because the pedal is not depressed and the vehicle is stationary no 3 amigos should light up, hence I think the fault might lie in the modulator's printed circuit. Time to strip, shave and resolder as per landroverclubvi.
Any other suggestion?
Best regards

Minnc, has the correct solution for this repair wire bypass, clear codes.

 

[pdxrovermech]

ive done the wire bypass 3 times. first two were successful, but no luck on the third. still have the SVS fault and amigos. Thinking it might be in the SLABS ECU now.

 

[robertofollia]

Thank you so much for input. Today opened connectors and all them were nice and clean, so no leaks. Bypass time then. Will have to wait as it's raining cats and dogs in Europe (yes I'm across the pond) and to make matters worse my recently fitted O2 sensor (no gen-you-win Bosch as they were out of stock) has died (Bank 1). The other one is fine. So 50% success with O2 sensors. One perfect the other one failed miserably...

 

[robertofollia]

Well, O2 sensor changed (one was dead) no sensor codes. Forgot to tell in the last post that, when pulling ABS modulator connectors, they were nice and clean but... the multiplug had not been pushed fully home. I recal never have touched them.
Could that be the cause of the SVS code? So far no codes but have to take it for a long drive to see if codes come back (17th dec)
Best regards

 

[robertofollia]

No more faults or 3 amigos came, but this time drive cycle was 20 minutes plus 5 idling. Before it would have triggered the 3 amigos.
Next weekend have a 2 hour drive so will test again
Anyway, in case it might interest someone it can be of help as a complementary repair fix to "option A" from landroverclubvi, I mean, there is another place where the solder can go bad on the printed circuit, one is at the "snout" we all know, the other one is where the "snout" meets the main board.
See this link

ABS Modulator Option A additional fix | DiscoTD5.com

www.discotd5.com

In my case I will wait until january (after MoT test time) in order to avoid a failed repair-mod and the be unable to pass MoT. In that case I might have 11 months more to find the cause of fault and repair it
Best regards to all

 

[mlnnc]

Why would you do Option A and not Option B? Option B is well-proven and a lot less work. Even Josh Salas, who wrote the original content at landroverclubvi, said there's no reason to do Option A.

 

[crown14]

FYI a lot of times these days all the wire in the SV switch unit is completely perished and if you have to buy a new one it can bump the total cost involved for option B more than a little bit

IDK if the above info makes any difference to option A because I can't remember what option A even fucking was

 

[mlnnc]

Yeah, I've seen reports and pics of shuttle valve switch modules where the insulation on the wiring is knackered, but if that's the case you'd need a new SVS module regardless of whether you address the failed solder joint via Option A or Option B.

Option A is carving up some hard plastic to get to the failed solder joint, resoldering it, and then covering up the butchery you've done.

 

[best4x4]

I've saved a few Shuttle Valve Switches with insulation which was completely gone by installing some 3/32 heat shrink onto the wiring and using 1 3M heatshrink butt connector in between the one wire which goes between to 2 switches. The #1 thing I see people doing wrong whenever they do Option B is they leave the black connector....... In order for Option B to actually work you MUST remove that connector so the bypass actually works! If left in place the Shuttle Valve Switches will still use the broken internal connection and the 3 Amigo's will come right back.

 

[JUKE179r]

In order for Option B to actually work you MUST remove that connector so the bypass actually works!

THIS!!!