4WD lights flashing and switches not working

My 2011 Jimny with dash switches to select 4WD has developed a problem, here is what happened.

I parked part on the kerb to go to the post office this morning, when I got back in and set off the 4WD green light was on solid on the dash, the 2WD/4WD drive switches didn't do anything and it felt as though it was in 2WD, there were no clunks.

Unfortunately there is no where to park round there so drove about 3 miles to work, taking it very gently.  During the drive the 4WD light and 4L light came on and started flashing about once or twice per second, the switches were still not working.  It has the feel of something electrical, perhaps a sensor/switch or something?

After getting to work, I switch everything off, waited a couple of seconds and started the car, the 4WD light has gone off, but the 2WD/4WD switches don't do anything.  If it is stuck in 2WD (which I think it is) at least I can drive around, but need to get it working correctly, especially with bad weather coming.

I know there is a good guide on the wiki, so lots to work through, but any suggestions where to start would be useful?

Robin
 

Sorry should have said, I didn't engage 4WD, it just came on all by itself. It wasn't on when I parked up and didn't notice if it was on when I started up or if it came on when driving up the road, but it was definately on after 50 yards.

Does the 4WD light come on if the vacuum fails? I suspect it doesn't which is why I think it might be electrical.

Further testing.

I left my Jimny for 30 minutes, went out started it up and it went through 2WD, 4WD and 4L correctly, I tried it several times.

Then with the engine running the 4WD light came on all by itself and I am back in the same position as before. I actually think the hubs clicked when it did it, so it might be in 4WD.

I am guessing that if I leave it for a few minutes it will drop out of 4WD.

I never had a similar problem but I would suspect an electrical problem. To solve this, I would first have a look at the switch and also clean it and then check the cables from the switch to the controller.

I checked it again, the 4WD was trying to engage (flashing prior to starting the engine, so not enough vacuum), but the 2WD switch turned it off.

I think it is definately electrical, almost as though something is chaffing and telling the unit to go in to 4WD. Or perhaps one of the relays is sticking?

wrote:

I never had a similar problem but I would suspect an electrical problem. To solve this, I would first have a look at the switch and also clean it and then check the cables from the switch to the controller.
 

Thanks, when you say 'switch' I assume you mean the 2WD, 4WD 4L switch in the dash board?  If there was a fault here, it could easily tell the 4WD system to engage.

I might have caught one of the switches this morning, putting a parcel in the car as I jumped in the drivers seat and placed the parcel on the passenger seat, it's possible I caught one or more switches.

A quick question, I know 4WG won't engage if there is a problem with the vacuum, but will it disengage if there is a vac problem?  I think it should, I thought the hubs were sprung.

Also as the transfer box doesn't use the vacuum to engage and I got the 4L light flashing, this kind of indicates a switch/controller problem?
 

The hubs will stay in whatever position they are left in. But as long as the transfer case returns to 2wd (which it should, even in the absence of the correct signal from the vacuum sensor) there will be no drive going to the front axle.
The problem is definitely withe switch/controller or the transfer box actuator, not the vacuum system.

Thanks everyone. It turned out to be the dash selector switch, I disconnected it and it stayed in 2WD. I took the switch apart, there is a small PCB with three switches, the 2WD is working fine the 4WD and 4L are both sticking.

I have bought another complete assembly from a breakers, but it is a shame the PCB mounted switches aren’t available, it’s a 5 minute job for me to change.