2WD/4WD Position Switch, How activated?

Joined: 18 Jun 2003 Location: Pretoria, South Africa

I have traced the fault of my Blinking 4WD indication lights to the switch on the Transfer case, (rear one on driver side) that does not switch when shifting from 2WD to 4 WD. I have removed the switch and it functions as should but it does not change state when the Transfer gearlever is shifted from 2WD to 4WD.

It apears as if, what-ever needs to release the plunger at the bottom of the switch, is not moving.

Does someone know the probable cause and if I can fix it without removing/striping the transfer case?

The pin of the switch is now pressed in, which gives a N/O circuit. When I change to 4WD it is suposed to change to N/C circuit, but as it does not, whatever should release the pin, is stuck.

What can I do??

model (NJ) 3.5 DOHC Auto

Willie

Joined: 26 Oct 2002 Location: Melbourne

There is a small ball bearing at the end of the spring which keeps the spring depressed and therefore the plunger when in normal contact with the shifter rail. When 4wd is selected the ball will sit in a notch/detent in the shifter rail allowing the spring to lengthen slightly and release the plunger giving the 4wd signal. If the plunger is not releasing in the switch itself then it will have to be replaced. But you could try spraying a little WD40 around the plunger to try and free it up.

Frank.

Joined: 18 Jun 2003 Location: Pretoria, South Africa

Frank,
I installed a brand new switch from the agents. I tested it by hand before installing. It worked fine.

Could it be the shifter rail which is not moving? I also got some info from the UK forum that the switch might be screwing in too deep so that it cant release properly when it gets over the notch. What do you think?

Willie

Joined: 26 Oct 2002 Location: Melbourne

Sounds like the return spring is knackered or is the ballbearing missing ??
It's pretty simple really, the ballbearing slides along the shifter rail until it falls into the detent knotch (on the shifter rail) when 4x4 is selected the spring will relax allowing the plunger to move outwards.
If the switch is new then probably the spring needs replacing or the ballbearing is missing ?? I'd be checking them first beyond that there is something wrong with the shifter rail itself and the t/case will have to be opened up to check.

Joined: 17 Nov 2003

Hi Guys,

I am fairly new to the pajero game and have a couple of questions about 4wd activation. Have been reading posts on here for a while and love the tips/advice from you guys . brilliant.

Frank you obviously know your stuff, you should get a job with gregories!!!

questions: (hope not to bore anyone these have probably been answered before but I couldn't find them in the archives)

1. what does the vacumm operated pin (whatever it is?) actually connect and disconnect to get 4wd
2. I know the cv's rotate when in 2h but does the front driveshaft and diff as well? I can't turn the driveshaft by hand when in 2h
3. if the centre difflock stuffs up and wont engage/disengage AND OR the front actuator thingy stuffs up and wont engage/disengage are there any situations where you wont be able to select or disengage 4wd

ie. stuck in 4wd and can't drive home on the tarmac, or 4wd wont engage and spend day in mud in 2wd....hope I explained this properly.

Just wondering if it stuffs up in the bush how do I get home if 4wd wont disengage. As on other 4bys when you unlock your hubs, they are unlocked.

Cheers, and sorry for the huge arse post.

Joined: 18 Jun 2003 Location: Pretoria, South Africa

How do I get to the 2/4WD return spring on the spring on the shifter rail?

I saw 2 plugs on the rear side of the transfer case more or less behind the Position switch. I removed the largest one which resembles a sump plug but could not see or feel anything inside.

I did not get to the second one as my car was being serviced and I was interfering with their work.

Willie

Joined: 26 Oct 2002 Location: Melbourne

Willie, there are 3 switches at the rear of the case which have the spring and ball :-

- high/low switch (white connector)
- 4wd position switch (black connector)
- centre diff lock position switch (brown connector)
There is also another detent plug with this group of switches (4 all together) which is not electrically connected (also has external spring and ballbearing) I think it helps to align the shifter rail.

There are 2 more detent switches located in the middle of the t/case that have built in springs & balls (can't fall out) :-

- centre diff locked state switch (brown connector)
- 2/4wd switch (black connector)

Which one did you replace ??
When you remove the switch the spring should be attached to it or still in the hole the ballbearing rests against the shifter rail under the spring tension.

Frank.

Joined: 18 Jun 2003 Location: Pretoria, South Africa

Frank,

I replaced the Rear one, 2/4WD position switch, on driver side. I know it is this one as, when I earth the connecter leading to the logic box, then the flashing stops if the transfer lever is set to 4WD. If I shift to 2WD then the flashing starts again until I remove the bridge to earth.

So, it seemed like a faulty switch. But now that I have replaced the switch I find that it does not change state when shifting from 2WD to 4WD mode.

Thus it seems the notch under the switch on the shifter rail is not moving forward and backwards. It seems to be stuck in the 2WD position which means the plunger( my switch does not have a ball) stays in the pushed in position. (n/o)

I tied spacing the swith a little with an extra washer, but that is deffinitely not the problem. If I space it so that the switch closes, then it does not open again when shifting. So the depth is not a problem.

It seems that what-ever needs to move under the switch, is not moving when the Transfer lever is pushed forward or backward.

Joined: 26 Oct 2002 Location: Melbourne

Ok the 3.5 V6 case may have a different arrangement to the 3.0 V6 case.
Honestly the only thing I can suggest is to remove the switch and have someone shift the lever while you try to see if the shifter rail is actually moving shining a torch light in the hole. See if you can see the detent grooves as there maybe some gunk sitting there stopping the plunger extending into the detent notch. Maybe feeling it with a screwdriver as the t/case lever is being moved to see if you can feel the notch and the rail moving. It will be very difficult but try removing the consol and viewing from the cabin. Other than that the case will have to come out for inspection if your absolutely sure that the switch is ok.
Good luck.

Frank.

Joined: 18 Jun 2003 Location: Pretoria, South Africa

Thank's Frank. I will see what I can do this week-end.

Willie