2003 Land Rover Discovery

I have had the four amigos for about 9 years. After doing some light off roading and getting stuck on a hill a two wheel drive Ranger went up with ease, I finally decided to do something about it. After much research, I decided to try the Autel Autolink AL619, which cost about $100 on Amazon. I am not disappointed.

I performed the option B bypass, to no avail. I did not have the scanner at this point so I had no idea exactly what was causing the amigos to remain.

I replaced the pads and rotors because my rotors were in poor condition, but still the amigos remained.

The Autel Autolink AL619 arrived in the mail. It was very user friendly and read the brake codes within a matter of about a minute of being plugged in. I've attached photos of the codes.






I cleared the codes with the scanner, which turned off the hill descent, traction control, and the brake light but the ABS light remained. I didn't have the opportunity to actually drive the Disco so I set it aside for another day. When I got to drive the Disco next, the ABS light went off, the hill descent and traction control lights remained off, and the brakes performed significantly better than they had for the past 9 years.

It's hard for me to believe the four amigos are gone. I can't wait to go off roading again to test it out.

Does anybody know if the brake fault codes require going through a cycle before reappearing, or if they appear at the same time the fault is detected?

 

I have had mine come and go over the years. It could be a bad ground, lose wire, or other sensor connection. When you did the option b, was there any brake fluid on the plungers?

 

You did Option B but the amigos didn't go away because the codes stay active until you clear them.
9 years of poor brakes is a long time to wait to get a $100 tool to fix them.

 

No, totally dry.

 

Quote:

Originally Posted by mollusc

You did Option B but the amigos didn't go away because the codes stay active until you clear them.

Thank you for both the helpful comment and the pointless comment. I had no idea the tool was only $100 until recently. My research earlier on revealed there was no actual economical code reader that would read the LR ABS codes, except the homemade device someone made long ago. I searched for it online and learned it was no longer being made.

This has been a spare vehicle for me that is rarely used. The brakes performed decent enough for regular roadway driving.
I was busy enough with replacing the cylinder head gaskets, oil pump, brake master cylinder, power steering pump, window regulators, and other odds and ends the Disco demands of its owners.

I posted this, in part, to help others that may be battling with the same demons. During my research on this forum, there was so much contradictory information about which scanners will read LR ABS codes and which ones will not. For anybody searching, I am saying that this Autel AutoLink AL619 ABS SRS scanner ($100) will allow you to read the LR Discovery ABS codes and will give you the option to clear them.

 

According to the RAVE, "After rectification of an ABS sensor fault, ... the ABS warning lamp remains illuminated after the lamp check, until vehicle speed exceeds 9.4 mph (15 km/h) (to allow additional checks to be performed)."

They appear when the fault is detected.

 

Thank you. I appreciate the response.

 

Or they left the black plug on the shuttle valves in place. Proper Option B has to have 2 things #1 a good ground & #2 black shuttle valve plug cut out completely. I've seen so many oh I've done Option B and still have issues only to find the black plug still wired up....

When you clear codes upon startup the ABS light will remain on until the SLABS Unit see's the ABS sensors report back with MPH data. Also if you have hard faults stored in the SLABS they will not simply go away. You must use a good scan tool which can access/read LR ABS Fault Codes.

 

Interesting that you mention that. While researching the option B repair, some videos kept the black plug on the shuttle valve in place and some did not. It seemed counterintuitive to bypass it, yet leave it in place, so I opted to remove it.

My ground is very good. I used a drill and wire brush wheel to scrape away the paint on the body where the nearby AC bracket mounts and soldered a ringwire connector onto the ground wire to fasten it to the body with the existing AC bracket bolt.

I am very happy with the outcome. All seems to be working properly. I have a new shuttle valve I will be installing soon due to deteriorating insulation on the existing shuttle valve's wiring, but it doesn't seem to be an emergent issue.

 

You can re-insulate the old shuttle valve switch assembly with some 3/32 heatshrink tubing. Simply remove all the brown cracked/broken insulation (should just crumble off with your fingers), then slide the 3/32 heatshrink over it and shrink it. For the back section cut it in the middle, install the 3/32 heatshrink tubing then use a red heatshrink 3M Butt Connector to tie both sides back together. I notched out the channel and the Butt Connector fit like a glove inside the channel. I've done that to probably 5-10 shuttle valve switches and I've either re-used them or kept them for spares. Black connector wise the #1 problem with the Wabco Unit besides the crumbling insulation on the shuttle valve switch assembly is the internal connector inside the Wabco Unit which carries the shuttle valve switch signal thru the Wabco Unit and back to the Slabs Unit. The Option B bypasses that weak link by going around that connection, but if you leave the black plug in place and still wired up you can cause it to still act up as one wire is still running thru the plug even after Option B is performed (Ground side of things if I'm not mistaken) as you cut the Yellow/Green wire with Option B and then go directly to the shuttle valve switch assembly. I have always removed it 100% then run the wires out like you did, and Option B then works flawless after that.

Looks like you did it properly & I'm 99% sure you can revive that old shuttle valve switch assembly with the 3/32 heatshrink and 1 3M Butt Connector.