Problem with Differential Lock

Huw Powell human747 at
Sat Dec 7 21:41:36 EST 2002

>  QT 90 NG

> Problem 1: This time I am having a major problem with the Diff Lock as,
> when I press / supress the button nothing happens. Even there is no
> light on the dashboard nor the button itself. I have checked the fuses,
> the relays which seem to be good. Anyone for any other ideas ?

it can take a moment to engage, though I believe one light in the switch
is supposed to come on right away, the other when it engages.

Your switch may be dirty, of course.  also, it won't engage over 15 (or
is it 25?) mph, and automatically disengages at that speed.

the vacuum supply to it might be bad/hose broken, etc., and the actuator
may also be busted, disconnected, etc.

> Problem2: I am having some trouble with the ABS. Whenever I touch the
> brake pedal, ABS starts to work. Even at speeds such as 20-30 Km/h,
> causing to extend my braking distance (imagine in city traffic !)...Thus
> after I go over few bumps it lights up the red light on the dashboard
> and turns off the ABS completely.

the consensus seems to be that this is due to crud on the hub teeth -
could also be a bad wheel pickup.  the solution is either to "fix it
properly" which seems to me to involve scoping the outputs of the
pickups, or disabling it, at least temporarily.

There is a relay under the knee panel with a red fuse in it, pulling the
fuse (or relay) will turn it off for good.  you'll be stuck with a
dashlight unless you remove the bulb, though.

Huw Powell

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