4x4 problem

Hello, 

So I wasn't able to find any thread for my problem or I'm bad at searching and wording it. 

I have Jimny 2018 3rd gen and what was happening is that the vacuum pressure switches were clicking, 4WD light and 4L light were blinking on the dashboard and AC wasn't working, all that just on idle, without trying to switch to 4x4 or something and when I tried 4x4, it didn't work, just some sound like air escaping came from under the car. During driving nothing was clicking or or blinking, but AC still didn't work. 

First thing I did was to change the vacuum pressure switches and that did help for some time, although 4L still didn't work. Now the problem came back by itself, I got stuck in 4L and when moving the car (on a straight line obviously) there was some like whistling sound from underneath. AC not working again. Somehow I managed to switch back to 2WD, but switches are clicking, lights are blinking and 4x4 and AC not working. 

Apparently AC is somehow connected with the 4WD system. 

Thanks in advance for any ideas on where to look or what this might be caused by. 

Petr

this is the sound of the switches. 

The 4x4 push buttons on my Gen 3 went funny, it kept going in to 4x4 and trying to go in to 4x4-L. It turned out to be faulty switches. I managed to get it in to 2WD drive and a temporary solution was to unplug the switch box, whilst I waited for a replacement.

I didn’t have any AC problems so yours might be something else, but erratic behaviour is often an electrical system fault, a chaffed wire perhaps?

Robin

The air con is enabled by the 4WD controller, on a lever transfer it cuts the air con when the hubs are moving- I have absolutely no idea why. I expect the push button is the same.

(I actually thought it cut the air con when in low, again I have absolutely no idea why it would, but a quick look at the timing signals for the lever transfer shows it disabled for 0.5sec when the lever is first moved.)

So if the 4wd controller is all confusicated the air con will be going on & off while it is trying to move the actuator in the transfer box and also lock the hubs. The actuator has to move first so the synchro cone in the transfer can bring the front axle upto speed so the hubs can then slide in without shearing off all the teeth.

I'd start by sorting out that escaping air noise, if the 4wd controller thinks the hubs don't move it will go straight back to 2WD and reject any switch to low.

So after extensive search through the whole vacuum system, trying different components from a different Jimny, it looks like the problem was not enough tighten electrical ground, which I found by pure accident and after tightening it, everything seems to work. Thanks for all suggestions!