I bought an Autel AL619 to read my ABS codes and it came back with “Shuttle valve electrical failure” 2 questions:
1) It appears that the so called “option B” is appropriate to fix this. Is there anything else that I should check or be aware of?
2) Does anyone know what kind of failure mode this fault puts the ABS/Traction control system in? I’ve heard that under some conditions those systems still function, although perhaps at a reduced capacity.

 

Yep, that fault indicates Option B. A lot of people go ahead and replace the switches and even the seals when doing Option B. I didn't, and all's well 8˝ years later. If you check resistance of the switches with a multimeter and inspect for brake fluid contamination (and find none), both as shown in Josh's Option B writeup, you should be good to go doing Option B only.

As for ABS function with that code, do you have the RAVE Workshop Manual? On p.877 of my PDF it shows the following default strategies for the SVS electrical failure fault.

 

Thanks for the information, I do have the RAVE but I’m not in a spot where I can take a look at it, so I appreciate you posting that info. Looks like I just have to carve out some time to do Option B!

 

It shouldn't take more than about 2 hours. Everything is very accessible.

 

Shhesshh. Just replaced my tires on my 99 Disco 2 at the shop. Soon as I cranked it up, boom, three amigos. Possible that they disconnected something?

 

It’s possible that a wheel speed sensor was disturbed somehow. I’ve also heard that brake dust can throw the 3 amigos, perhaps some of it was disturbed during the tire swap (or the complementary brake inspection which is sometimes included with new tires). If that’s the case try spraying your wheels or blowing them out with compressed air.

 

much thanks, I saw the cable got disconnected when I went looking. I connected it (driver rear). Everything went off but I’m getting a 1590 on the code with no lights on??

 

P1590 is triggered whenever the Three Amigos appear. Clear it, clear the Three Amigos, and see how it goes.

 

Take all of this with a grain of salt but here is my understanding, hopefully you can use it as a jumping off point. The 1590 code is a “Rough Road” code, from what I’ve read if you are driving over a washboard or other rough surface it can induce a resonance in the abs sensor to hub distance, if that distance gets too high the code will trigger as the SLABS can no longer relyon that signal. I think that this is a hard code which has to be reset with a scanner even after the issue has been resolved. Perhaps it popped on in the background when the 3 amigos were thrown because the wheel sensor was unplugged? I hope that’s all it is and you can clear the code and be on your way. Good luck!

 

Thanks for all the help!