ABS Unit - My Fix Didn't Work After All!
So, I purchased my VX with the ABS light on steady. I didn't really care too much as I'm not a huge fan of ABS anyway. The PO told me he read the codes and thought it was one of the front wheel sensors. After reading up on how to read the ABS codes I jumpered out pins 12 and 4 on the OBI connector and was able to read the codes as 43 and 44. Both of these are related to the FR Solenoid Valve(s) not one of the wheel sensors.
This indicates an issue in the ABS control unit and since someone on Ebay fixes these I came to a few conclusions:
1.) If someone is repairing these then it is probably an electro-mechanical problem since no one is going to be component troubleshooting.
b.) Since the ABS unit works by pulsing solenoids in the hydraulic system the problem probably resides in the connection to the solenoid coil but not the coil itself. Again, because this guy is fixing them.
III.) Since he claims that his fix is permanent it seems logical that he has found one particular weak point and is going in and replacing fragile wires with beefier ones.
After the difficult removal of the ABS control part as described by others in this forum I began trying to disassemble the unit. This proved more difficult than I anticipated. I tried cracking loose the 'D' shaped cover that hides the processing board without success. I tried using a heat gun... Nope. Finally I just cut it off flush to the case it's attached to. This exposed the board which is covered in goo/slime and there are VERY fine wires that come from each solenoid and soldered to the board via tiny SMD pads. I carefully cleaned off the goo along the connector and the area on the board that the wires attach to and in the process broke a few off the board. I suspect that the one that controls the FR was already broken. I then used a few strands of fine wire twisted and tinned to replace the original wires and soldered them in place.
Now I should mention that I have been trained in SMD soldering techniques but... It was a long time ago, I never used the skills I learned, I don't have any SMD soldering equipment, and I didn't have a good magnifier. So, I used a regular soldering iron with a too fat tip and a little plastic magnifier from a glasses repair kit. Not ideal tools to say the least.
Once finished I left the cover off and re-installed the ABS controller and fired up the car. The ABS light went out after it's self test! I can't believe that worked! I fully expect it to fail again so I'll keep you guys posted but under the right conditions with the appropriate tools I can see this fix working. I just wonder how Ebay guy gets the cover off on the ones he fixes. That and the bottom left torx screw the holds the unit are the stumbling blocks.
Here are a couple of photos of my fine craftsmanship :mbrasd:
http://www.vehicross.info/gallery/da...Import_009.jpg
This is rotated so that it appears in the same orientation as it would be on the car. If you can zoom in you may see the two ultra fine wires that I left in place.
http://www.vehicross.info/gallery/da...Import_010.jpg
This shot shows the 'D' shaped cover that I cut off.
Cheers,
Scott
Update. It didn't work after all.
So I finally got the VX out on some dirt and was able to lockup the brakes. So, the fix did not work. The ABS light does not come on at all anymore so I'm gonna just leave it alone now. I mentioned earlier that I don't really like ABS that much anyway so no big deal. I started out with a VX without ABS, with an ABS warning light, and a rebuildable ABS controller. Now I have a VX without ABS, no warning light, a non-rebuildable ABS controller, and some knowledge. So it's pretty much a wash. I do still think the troubleshooting and diagnosis is fairly solid but my execution was sorely lacking. Oh well...
FWIW I think if you want yours rebuilt the guy that does them through Ebay offers a good value. :thumbup:
