rear difflock wont engage

[kombosa]

hi,
i been following the site for ages and this my first post.
i have 2013 lwb 4motion transporter with rear diff lock,i had it since new.no dramas.
today i left the bitumen and tried to engage the rear diff lock.i like to do this semi regularly.if you don`t use you loose it.any way today the dash light only briefly flashed,the push button stayed illuminated and the diff lock did not engage.
upon returning home i tried it again with the side door open and i think i can hear something happening in the diff area but i can`t confirm this....
any thoughts would be welcome.

[scotlandstu]

I would be checking the vacuum pipes from the brake servo first, good luck

[weonarok]

I would be checking the vacuum pipes from the brake servo first, good luck

So do Transporters use vacuum to engage the diff lock?

Amaroks are fully electronic and have five wires going to the inside of the diff which also has a sensor to detect and illuminate the dash light when it's engaged. Sometimes I need to idle forward on a gentle turn so the dogs can line up, otherwise it can 'flash on the dash' before 'timing out' and not engage.

If you have had it since new then I'm guessing you still have the manual that may be worth reading up on to see if there are certain situations where it won't allow it to engage until the planets align, so to speak.




Cheers dave

[scotlandstu]

Yeah, see page 42 https://vwpress.files.wordpress.com/.../ssp_333_e.pdf
From 2004, different components on the newer ones, but similar design.

[kombosa]

hi guys,
thanks heaps..great info...i`ll start with the simple..noises from rear diff and then check relay.after that i`ll have to regroup.

[hoddy]

My diff lock went a few years back. Light wouldn't turn on nor engage lock. Can't recall whether there were still noises attempting to lock it.
VW found internal failure of locking solenoid.
Part # 037906283D

[kombosa]

the offending component is throttle control,which appears to operate via vacuum.very expensive to buy through the aussie krauts.has any one dealt with oemwolf.com?