Hi guys, I have a hacked to pieces 4x4 Isuzu bighorn/trooper (Holden Jackaroo). Its old as the hills and seems to have an extremely uncommon engine in it (UBS13, G200z petrol 2L)

It is a manual transmission, with a manual selecting gear stick for 2, 4H and 4L. It also has manual lockers.

The problem I'm having is it doesn't seem to be going into 4x4 no matter what I select. I can feel a small crunch when going into 4H or 4L. but its simply not engaging. Now I have been looking at forums for a week now trying to find useful information. I have come across many regarding SOTF vacuum issues etc. However after comparing all of those photos and walkthroughs, I'm confident my truck is too old to have this system. I also get no 4x4 light on the instrument cluster. Although I don't even know if I should have one as its quite an old model.

This thing has had a HAAAAAARD life. It also has about half the wiring chopped out of it.
If anyone could give me any info on parts to check, or perhaps any information on how to hardwire/bypass solenoids to make it always engage 4x4? (it never sees any roads)

Any help or ideas are appreciated.

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