Trouble with auto hubs/4WD system

Hello everyone!

Before posting, I've had a little search around and read up on how the auto hubs work, and I think I've just about got the gist of it. My DIY skills are very limited, but I like to think I could at least understand what the mechanics at my local garage tell me!

Basically I was wondering whether anyone could help narrow down what the issue might be before I spend many millions of pounds on labour fees, seeing as my mechanic is stumped! I have the old 'Flashing 4WD light' issue and I've searched on the forums to find the first checks I have to do. I've checked the hubs and all the pipes and cables etc are still attached. I offroad regularly so it's very possible something got pulled off but I can't see anything obvious. Essentially the vacuum isn't being completed from what I can gather, and there's no 'clack clack' from the hubs either.

The second issue that came on at the same time is that the Jimny won't go into 4WD either. I assume that even if there was a problem with the hubs the truck would go into 4WD? So I'm guessing it would be the solenoids or some other electrical issue affecting the whole system at once?

What I was after was some indication as to what it would be and I could point my mechanic in the right direction seeing as this is a fairly specialised issue. I'm also concerned that if fit manual hubs the 4WD still won't work!

I really appreciate any help anyone is able to give

Sam

My vacuum hubs don't make any "clack-clack" noise, but the 4WD still works, so it's not a 100% reliable indicator.

As for manual hubs, it should be fine. All the dials do on the manual hubs it allow you to engage the hub to the drive shaft splines. It removes completely the need for the vacuum system. You are then left with the transfer box to give you the low or high ratios.

Is it a push button or lever 4x4

GuardianAngel wrote: My vacuum hubs don't make any "clack-clack" noise, but the 4WD still works, so it's not a 100% reliable indicator.

As for manual hubs, it should be fine. All the dials do on the manual hubs it allow you to engage the hub to the drive shaft splines. It removes completely the need for the vacuum system. You are then left with the transfer box to give you the low or high ratios.

So I guess if I fit the manual hubs and the 4WD still isn't engaging then it narrows down the fault finding process? Is there anything that would affect both the hubs and the 4WD, like a cable or electrical switch that could be broken?

markyp2000 wrote: Is it a push button or lever 4x4

It's a lever, and one I move it into either 4WD high or low it takes about 15 seconds for the light to flash. I still get low ratio gearing, just as far as I can tell (by the amount I was sliding about in the mud!) no 4WD.

I also lifted one of the front wheels off the ground and drove forward with the handbrake on in 4WD and the wheel didn't spin, which if 4WD was working it should have?

samsamsam wrote: It's a lever, and one I move it into either 4WD high or low it takes about 15 seconds for the light to flash. I still get low ratio gearing, just as far as I can tell (by the amount I was sliding about in the mud!) no 4WD.

I've got fixed hubs and my 4wd light takes about that to start flashing.

samsamsam wrote:

GuardianAngel wrote: My vacuum hubs don't make any "clack-clack" noise, but the 4WD still works, so it's not a 100% reliable indicator.

As for manual hubs, it should be fine. All the dials do on the manual hubs it allow you to engage the hub to the drive shaft splines. It removes completely the need for the vacuum system. You are then left with the transfer box to give you the low or high ratios.

So I guess if I fit the manual hubs and the 4WD still isn't engaging then it narrows down the fault finding process?

If you fit MH's then all the transfer box is doing is giving you 2WD high (normal) and 2WD low. There will be no 4WD activation via the 4WD selector. It will be the MH's giving the 2WD to 4WD selection.