4WD control lever, center diff & rear diff lock.........

[sae70]

.............when I use the 4WD control lever to select HL or LL all seems fine on most occasions but every now & then the center diff lock indicator light flickers or does not come on untill you give the 4WD control lever a joggle sometimes this is more persistant than others All feels as it should with regards to the center diff locking or Low Ratio being engaged even when the indicator light is not illuminated so I just wanted to check that this is just an electrical loose conection issue & can be easily rectified

The other question I have is that after I've selected LL using the 4WD control lever & the center diff lock indicator light is on when I then turn on the rear diff lock the ABS light comes on & the rear diff lock indicator light comes on but flashes untill I've pulled forward maybe 2/6 meters then it remains solidly on I've not yet selected the rear diff lock & had it lock straight up without moving slightly forward Is this the norm

Mmmm......I've not tried to select the rear diff lock when the center diff lock indicator light is playing up I guess it's this signal that tells the rear diff that it is OK to lock up..........hang on a mo..........flick through owners manual.........Ah the owners manual gives the impression that the rear diff lock will only operate when the 4WD lever is in the LL position 'The diff will also unlock if you shift the 4WD control lever to H or HL' so there must be another switch to tell the rear diff lock system that the 4WD control lever is in the LL position & a seperate switch that illuminates the center diff indicator light when the center diff is locked I wonder if this also sends a signal to the engine mangement system for any reason to let it know that the center diff is locked

Can anyone shed some light on any of the above for me

 

[Chris]

I think that you have answered all of your own questions there. The only thing that i can offer in addition is the the system gets a lot slicker if used regularly. I presume that you've done the obvious stuff like checking oil. Other than that it sounds like it's operating as it should. use it and it will all engage more easily.

Chris

 

[BobMurphy]

There are two switches on the Transfer Box (three if you have an auto-gearbox). These have a sprung plunger that drops into a notch on the two selector shafts when you are in :

A: Centre Difflock (right hand / UK offside switch).
B: Low Ratio (left hand / UK nearside switch).

The switches are therefore normally in their compressed (open circuit) position.

As Chris says, if you don't exercise them from time to time they can become sticky and probably the contacts get oil on them.

The two switches can be seen high-up on the box here:

There is just one more thing to check though - if the switches have been disturbed / removed and have new alloy sealing washers, just make sure that they are not screwed in too far or they won't operate properly.


When you engage the centre diff, the light is triggered by the lever position whereas the selector is sprung-loaded and the diff lock will only operate when the gear teeth line up and the system isn't under load. Just back off the throttle a bit and it should drop in. The light doesn't mean that its engaged (yet).


When engaging the rear diff lock you have to be in low ratio. When you do this the Diff Lock ECU disables the ABS and the ABS light comes on. The switch in the transfer box tell the ECU that low ratio has been engaged. This is not sprung and you can feel it going in through the lever. The book says 5mph or less if my memory serves. This has to be done before the difflock switch is turned.

Engaging the rear locker activates the motor in the rear diff and there is another switch on the diff that detects the locker's selector moving. This is also a sprung set-up so again, won't engage until everything is relaxed and lined-up. The Rear diff lock light is driven by the rear diff switch, so will cause the light to flash until its engaged. Its quite normal for the light to flash for a bit until the locker engages.

Four switches and a computer to 'help you' . . . . Too complicated by half


Bob.

 

[sae70]

Thanks for your replies Chris & Bob

So all seems to be working fine but I just need to keep playing with it all to loosen it all up then Sound like an excuse to get off road to me Shh... the wife just walked in

Bob that transfer box is toooo........ shiney but thanks a picture conveys a thousand words

 

[BobMurphy]

Bob that transfer box is toooo........ shiney :

That's 'cos it was all stripped and cleaned . . .

Not a pastime I'd recommend





Bob.