In my continuing struggle against the 3-4 Amigos, I am considering trying the "Option B" fix to bypass the often bad solder joints in the ABS unit itself.

The messages I get from my code reader are the:

- Rough road condition implausible in the ECU

- Right rear sensor signal in the ABS/SLABS

Are these codes consistent/possible with a solder joint failure?

I have a spare ABS microswitch to experiment with as I replaced the old perfectly good (as per ohm test) microswitch with a new one in an attempt to throw parts at the problem, so no problem cannibalizing that.

Before I jump in and do Option B, however, I am wrestling with trying to understand the possible relationship/connection/correlation between a bad solder joint in the ABS unit and the codes I am getting about a bad speed sensor?

So a couple of questions:

Are the codes I am getting consistent with a 3-4 Amigo state?

Can the bad solder joint in the ABS Unit really cause the SLABS to throw a wheel sensor error code?

Has anyone ever used the Option B bypass/fix to correct an error like mine (code indicating only one bad sensor)?

 

The reason I ask these questions about whether my specific codes are consistent with a 3 Amigos and whether the Option B will fix it is that in a previous thread on this general topic, I explained that I had replaced the microswitch and some smart on the forum (Disco Mike) asked why I had done that and whether I had gotten bad ABS switch error codes.

This led me to wonder whether Option B only fixes certain three amigos states and whether my code combination (rough road + sensor signal) was one of them.

 

Option B only fixes the ABS Modulator solder issues and has absolutely no connection with any wheel sensors apart from they send a signal and regulate the ABS Braking function. If you are showing a duff wheel sensor that is your problem and nothing to do with the ABS Modulator. There are various issues that may cause the 3 Amigos, 1) Bad earth ground somewhere or low battery power. 2) A problem within the ABS Modulator. 3) One or more wheel sensors is not working properly either the electrical connector or the sensor is duff or the wheel bearing is sloppy or loose. 4) You have a duff Braking ECU with an internal fault. (the ABS Braking System is also used by the Hill Descent and Traction Control, hence the 3 Amigos)

You need to bleed the brakes correctly first using the correct sequence and run the ABS Modulator with a diagnostic tool as per the RAVE recommendations, especially if you have replaced or tampered with any brake parts and lost brake fluid.


You don't necessarily need the Lynx as there are many diagnostic interface tools that can activate the ABS Module known as a 'power bleed'.

 

I think "Option B" only corrects the shuttle valve failure error code? It worked in my rig. If you have a RR speed sensor code, I'd be looking at that. When I purchased my Disco, the seller said it had a bad LF bearing/speed sensor that was causing the 3 amigos to occasionally appear (Indy LR shop told him this). So we agreed on lowering the price a couple hundred more dollars and I bought it. I took the disco to a Indy LR shop local to me, he read the error code and it said "Shuttle Valve failure" and we'll fix for 700.00!! Yikes. So that was when I discovered Option B, AND this website. Option B was brand new at that time....4 or so years ago??Well it works, and I haven't changed out any speed sensors. I do have a touchy LF brake under hard braking, or in the snow...The "Anti Lock" brake is not so anti lock....Not sure if it's related to Option B or not. This was my experience.

 

I have the rough road implausible and a LF wheel sensor error, but I don't have any amigos. Not even my CEL is lit since I took care of all my emissions codes.
At one point I did see a shuttle valve error in the ABS codes but everything I have been reading about tells me that that's the only one of mine that would be fixed by doing Option B.
You might want to verify that your wheel sensor isn't the problem, but I'm not convinced that Option B will get rid of your amigos.

 

Just a small afterthought, if you repair any offending problem that displays a diagnostic code unless you then 'clear' those codes they will remain resident in the ECU/BCU or wherever and re-appear each time you switch on the ignition. Many assume that fixing the fault is the end of the story but unfortunately not. Once fixed ALWAYS clear the codes with a diagnostic tool otherwise they can still bite you.

 

Just went through this. The simple answer is no. I had to have a new wheel speed sensor installed in addition to option b performed. They are separate fixes.

And to be clear, according to GBR who did the work for me (yes, I'm lazy) you need the new style of wheel speed sensor that is soldered directly in under the dash, and they even had issues with aftermarket ones and said it would be best to get the OEM ones that are more $$$. I trusted them and a week later all is well.

 

Would temperature, i.e. excessive heat, have any affect on the ABS?? My ABS comes on once, twice a day. During the cold snap in Portland Or, (mid to upper teens) ABS came on only one time. Warmer temps cause the 3 amigos to light up. I have no scanner, so can not introduce the error code.

 

Without a scanner, you will never fix the issue.

 

I had rough road and RF speed sensor codes when I bought my rig. The wheel bearing was toast, so I ordered a new bearing/sensor combo and installed it. Cleared the amigos and that fixed the problem. Speed sensors are an easy and cheap fix, provided the bearing is still good.

I found another code lurking around (no lights) for short in the brake system for HDC. Turned out to be a nicked wire in the loom for the rear door.

Fix what's broken, then wait for the the next issue. No sense on fixing a problem which doesn't exist, yet.