The three amigos have been coming on intermittently on our Discovery 2 recently, so I borrowed a Snap-on Solus code reader and got the following:- 134 shuttle valve switch electrical failure.

I cleared the code, checked for engine fault codes, then got a boing sound and the three amigos were on again. Checked the ABS codes again and got 66 shuttle valve switch electrical failure.

My question is, does this sound like a wiring problem rather than complete failure of the shuttle valve switch assembly? If so, then I guess I just need to do the wiring mod, so that it goes direct to the vehicle earth.

Glen.

Yes I would say wiring mod

depends, you must measure the resistances of the switch pack, if the switch pack is ok the wiring mod is enough(in most cases), it'a removable with the module in situ, you just have to unclip the pipes to gain more room and be a bit contorsionist... search the web cos there are some tutorials... BUT if you see traces of brake fluid on he switches you must remove the whole modulator and replace the SV seals or buy the expensive SVS assy(SWO500040)... see this thread Three Amigos - Fault Diagnosis - Australian Land Rover Owners at post #7 it's a graphic explanation of the whole thing.