Flashing 4WD Light Confusion

Several days ago I helped a friend convert his 2016 Jimny to manual hubs. His system developed a vacuum leak and I convinced him that it might make more sense to go to manual hubs. After installing the hubs we shorted the vacuum switch circuit at the connector and plugged/capped the vacuum system. We began to drive to an area where we could test the system to insure everything was working correctly. About a minute out, the 4WD lights began flashing. Going back to his garage, I took a cursory look to insure there weren’t any obvious problems with wiring connections. We then did a test to see if the transfer case was engaging.

The source of my confusion:
1. Usually (but not always) when the car is first started, the 4WD lights aren’t flashing and take anywhere from 10 – 15 seconds to a couple of minutes before they do.
2. If the lights aren’t flashing, pressing the 4WD-H button will give a steady 4WD light and pressing the 4WD-L button will add a steady 4WD-L light. The cycle can be reversed by pressing the 4WD-H button, causing the 4WD-L light to turn off and then pressing the 2WD button, turning the 4WD light off.
3. If the 4WD lights are on as outlined in item 2, they will still begin flashing within a couple of minutes.
4. The 4WD lights have no bearing on whether the transfer can engage. Doing the ‘one wheel lifted’ test, the transfer will engage or disengage after pushing the buttons whether the lights are steady or flashing.

The manuals I have access to don’t cover the newer model Jimnys. Anyone with ideas on how to get these lights working properly?

Thanks
Bob

There are positional limit switches inside the transfer box.

My 4L switch failed and I got much the same symptoms.

There is a sequence that the lights flash in, the speed of the flashing will tell you where the failure is.....

I cannot post the info on the forum (copyright) but if you PM your email address, I will forward the mail to you.

What I understand from a quick refresh, it will be that one of the switches is not giving the "made" signal, £58+ vat to replace.

sniper

Thanks Lambert. Going back to have the full electronics operate as if standard would be a good place to start. I will reconnect the vacuum switch and simply cap the vacuum lines at the hubs. That would be a simple test.

Sniper: Thanks for the response. According to the manuals for vehicles up to (I think) 2006, the limit switch would be the prime candidate based on flashing intervals. I'm simply not sure with the newer models. There is no longer a 4WD control module and a transfer control module. Both have been combined into what is called a 4WD shift control module. It certainly wouldn't surprise me if the diagnostics would still apply but I was thrown off by some of the details I described. A few questions for you:

Did your lights begin flashing even if you didn't attempt to put it in 4WD?
Was there a delay when you first started your car before the flashing began?
When you began having flashing lights were you still able to engage 4WD?

Thanks again to you both.

My bad, didn't know of the control upgrade..... if the box is the same? would they not use its outputs in a similar manner?

Try looking at the switch changes on both 4H and 4L with a multimeter, see if the outputs are the same. It might identify a faulty switch which would confirm the above..

Good luck.

sniper

Don't feel bad Sniper. I didn't either until I contorted myself enough to reach under the dash in an attempt to check some of the circuits through the connector pins.

What used to be E74 (4WD controller) and E147 and E148 (transfer controller) are now one connector. With none of the wire colors matching the manual, I'm now lost on that part of the diagnostics.

I'll try a little more trouble shooting and keep the forum posted.

Lambert wrote: What were the original conditions that lead to the fitment of the manual hubs?

Although I wanted to focus on the 'normal' issues first, there is more to the story. The vacuum line was damaged but how it was damaged adds to my uncertainty. When my friend first discovered that he couldn't engage 4WD, the Jimny was driven to his garage and parked. A couple of days passed when he phoned me and asked if I could help troubleshoot. When I opened the hood of his car, a rat ran out (yes it did startle both of us) and it became obvious that it had made the engine compartment its home. Luckily, based on limited damage, I think it was for a relatively short time. I found where it had chewed through a vacuum line (the one that leads to the vacuum tank) and it had chewed a small area of cable covering near the battery. Reasonably close inspection seemed to indicate no damage to the wires. I suggested to Joel that manual hubs might be a good decision. After he agreed, we began a search for AVM hubs but they aren't readily available. For that reason the 4WD was left unused for several months. After getting the hubs, the right side hub had the same problem as was posted by a member a while back. When the hub fasteners were torqued to spec, the wheel wouldn't rotate. Decided to pull the hub nut and have it machined down slightly and reinstall. Another couple of months for that to be completed. It sounds from forum experience that the Jimny doesn't care for not having its 4WD system excersized regularly. Now I am left unsure whether an intermittent short or a long delay may also be contributing factors to his problem.

Agree with both your electrical and mechanical comments. My first step will be reconnecting everything as designed except using manual hubs and capping the vacuum lines at the hub. This will communicate a real vacuum to the 4WD controller. If that doesn't work, I may look at the actuator based on this post (Really....I do search before I post): No 4WD and Flashing Lights . A faulty limit switch also falls in line with Sniper's comments.

My confusion may be based on what it is I expect if it were a failed actuator/limit switch:
If there was a delay before the lights began flashing, wouldn't it be relatively short and the timing consistent?
If the actuator/limit switch is faulty, doesn't that prevent it from going into 4WD (limited shift operation)?

Currently, I need to ensure it's in 2WD and then remove the jumper so that Joel can use the car for a few days. When I can get back to it, I will update the thread.

Thanks for the comments Lambert.

I wanted to post these pages I found from a technician training manual in case they are a benefit to anyone trying to determine problems with their transfer case.

The car still isn't available to troubleshoot but I did have a chance to do a DTC check. The code his car has is 65 so I guess that should narrow it down to our rat friend. Unless I'm reading the 'Detecting Condition' wrong, the controller is looking for the vacuum switch to remain ON for a minimum amount of time.





Edit: I think I am reading it wrong. I think code 65 is saying that if the vacuum switch remains on even when VSV2 is off, a DTC will be generated. I will see when I reconnect the vacuum switch and vacuum lines except plugging the lines at the hubs. If shorting the switch is an issue on the newer 4WD systems, all the symptoms would fit.