2009 G3 Jimny - No 4WD-L after manual hub switch

Good afternoon all,

I wonder if any of you might have any ideas on this. Ive swapped out my vacuum hubs for manual ones (AVM), blocked the flexi lines where they meet the metal lines underneath the battery (And at the metering valve as I was mistakenly under the impression that would be sufficient. That flexi sadly broke apart when trying to remove it so ive blocked both sides and put the metering valve on the vacuum side)

From that I simply had flashing light on 4WD-H mode and refusal to engage 4WD-L at all (with a beep)

I then tried the suggestion from another thread of shorting the switch. This seems to allow it to go into 4WD-H without the flashing light, but still no 4WD-L (same beep, disengages entire system back into 2WD)

I dont actually know whether or not with the switch shorted im actually getting drive to the front, havent had any loose ground to try it out on; but presumably all is not well if its not engaging 4WD-L

Am I missing something obvious in the process?

Are you in neutral and/or have the clutch pushed in when trying to engage 4WD-L?

I think the wires to the transfer box are subject to breaking and it might be worth checking the BigJimny wiki for the 4WD fault finding guide to look for other faults.

You can check 4WD-H operation by jacking one wheel, with it in 4WD the wheel wont turn, but it should in 2WD. Repeat for the other side.

You might as well check that the manual hubs are locking at the same time trying to turn the wheel whilst jacked.

Gearbox in neutral; clutch out, engine running.

Ive since also discovered that once its driven more than a few yards if the switch is shorted both lights come on and flash until the engine is turned off again so ive unshorted the switch for the time being.

I'll jack it up and check those bits as you suggest tomorrow when the light comes back.
Ive also ordered some flexi hose to replace the section between the vacuum pump (i think) and the check valve. Since that broke apart ive just blocked both ends of it. It might be that this is part of the problem but until the new hose arrives i cant bypass it as it doesnt reach any more

There is no vacuum pump. Vacuum comes from the inlet manifold. But with the white connector to the vacuum switch shorted none of this should matter, so do that.

I've replaced the line from the inlet manifold to the check valve (and through that to the series of pipes under the fuse box) so that part is now as it was before. Re-shorted the white connector block.

Still the same unfortunately.

If the engine is off:
4WD selection results in flashing green light
4WD-L selection results in loud beep, both flashing lights and then back into 2WD mode automatically

If engine is on, gearbox in neutral:
4WD selection results in solid green light (unknown if drive is going to wheels yet)
4WD-L selection results in same beep, both flashing lights etc etc.

Havent taken it up the road yet to see if the connector being shorted still results in both warning lights coming on when driving as i also discovered a bald tyre so its in for 4 new ones on Saturday.

I can hear what i presume to be the transfer box engaging whenever 4WD is selected, but not 4WD-L

Edit - Image added for clarity