Shuttle valve electrical fault disco 2

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Sethballard

Member
Posts
13
Location
Orpington
New Land Rover owner alert!

I've had the discovery for a few months and three amigos kept coming and going, finally got it plugged in and the reading was a shuttle valve electrical fault, been told would need a Land Rover specialist too look at it as my mechanic doesn't want too **** the motor up even more..

I'm not a mechanic in the slightest so Just wondering if anyone had same problem and would know rough prices on repair etc.

Thanks in advance - Seth
 
Just in case the "Search function" isn't working as it should, I've attached the information for the "Option B" fix.
There should be no need to undo any of the brake pipes from the ABS modulator, it can be lifted off its mountings if you're careful. A search on google will bring up a whole load of information. Search "SVS Mod".
The "Option B" write-up also shows how to test the shuttle valve switches using a DVM.
I have applied the modification a number of times very successfully. It must be stressed that the modification is unofficial and it's unlikely that any LR garage would install it for you, preferring to sell you a new ABS modulator instead and your local indie garage might need a lot of convincing to carry out the mod for you too. Your best bet is to do it yourself or get somebody to help if you aren't that confident with vehicle wiring.
 

Attachments

  • DISCO ABS FAULT.pdf
    338.6 KB · Views: 1,077
  • OPTION B.pdf
    1.1 MB · Views: 1,253
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Cheers mate, poxy phone won't let me open the files, but I'll ask the mechanic I use about it and hopefully he'll know more about it, thanks for the help
 
Cheers mate, poxy phone won't let me open the files, but I'll ask the mechanic I use about it and hopefully he'll know more about it, thanks for the help
You should be able to open those files if you have something like the "Adobe" pfd reader app. There are other apps which can also open .pdf files, it is after all a well known, well used standard for documents.

The modification in "Option B" essentially bypasses the two pin connection inside the ABS Modulator which can cause the failure by using a bit of external wiring. A wiring diagram might help you.

Shuttle valve wiring.jpg
 
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Alright mate I'll bare that in mind, I'll be honest anything electrical goes right over my head but very thankful for the help, I'll show all this too my mechanic who will understand it, many thanks
 
You should be able to open those files if you have something like the "Adobe" pfd reader app. There are other apps which can also open .pdf files, it is after all a well known, well used standard for documents.

The modification in "Option B" essentially bypasses the two pin connection inside the ABS Modulator which can cause the failure by using a bit of external wiring. A wiring diagram might help you.

View attachment 148373
What does this mod actually do? Does it bypass the switch completely or just a function within the switch? From what I can see, the SVS tells SLABS when to switch from normal braking to ABS or HDC and open up the necessary solenoids and pump(s). Just curious!
 
What does this mod actually do? Does it bypass the switch completely or just a function within the switch? From what I can see, the SVS tells SLABS when to switch from normal braking to ABS or HDC and open up the necessary solenoids and pump(s). Just curious!

There is a small two pin connector inside the ABS modulator which connects to the SVS switch plate. In some cases that small connector can suffer from either dry joints or the solder joint becoming crystaline resulting in a failure of the connection between the SVS switches and the SLABS ECU.
The modification hard wires the SVS switches to the SLABS wiring, effectively by-passing the troublesome two pin connector in the ABS modulator.
The connector can be repaired but it requires removal of the ABS modulator from the vehicle and a total strip-down to gain access to the connector. The "official" LR method of dealing with the problem is to replace the ABS modulator completely. Neither of which are particularly cost effective when you consider the cost of the modification could be as little as two bits of wire.
 
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There is a small two pin connector inside the ABS modulator which connects to the SVS switch plate. In some cases that small connector can suffer from either dry joints or the solder joint becoming crystaline resulting in a failure of the connection between the SVS switches and the SLABS ECU.
The modification hard wires the SVS switches to the SLABS wiring, effectively by-passing the troublesome two pin connector in the ABS modulator.
The connector can be repaired but it requires removal of the ABS modulator from the vehicle and a total strip-down to gain access to the connector. The "offiicial" LR method of dealing with the problem is to replace the ABS modulator completely. Neither of which are particularly cost effective when you consider the cost of the modification could be as little as two bits of wire.
That makes complete sense now! Thanks.
 
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