1993 FXJ80 center differential lock not engaging.

[Aaron93LC]

Hello!

I just purchased my first Land Cruiser and have encountered a problem already. The AWD system is working, but when I shift into 4L the CDL is not engaging. I have tried the suggested test of turning the key to the on position and shifting while listening for the click and whir of things engaging. There is no sound at all. The dif lock fuse is not blown. Can anyone suggest where I might look next? Thank you in advance.

 

[Chris]

Best thing to check is that the connectors on the transfer case have not been un coupled. I had an 80 recently with exactly this problem. There are a series of connections, some that run the locker and some that detect locked and some that detect low range engaged. In all there are some 4 to 5 plugs from memory. Get underneath and have a really good look around. They aren't all easy to see so follow the wiring loom. Someone may have disconnected it so that they keep an open diff when in low range. The other obvious question is - have they put the optional switch in the dashboard instead? That's what we mostly do over here.

Welcome along

 

[frank rabbets]

Chris has obviously got up early for his presents.

 

[Chris]

Actually Frank I woke at 05.00 with some neat ideas for the wheel carrier. I just wanted to get them sketched out before I forgot.

 

[Aaron93LC]

Merry Christmas!

1. Nope, the switch was not added, although I intend to to that once I get the CDL sorted.

2. I'm pretty sure this thing has never seen 4L in it's life.

 

[Aaron93LC]

"To do" that. Haven't had quite enough coffee this morning!

 

[clivehorridge]

Could have been worse, might have been do do

 

[yogi]

Are you partaking of an after dinner sherry there Clive????????

 

[clivehorridge]

Are you partaking of an after dinner sherry there Clive????????

not sherry, but several, yes!

 

[Aaron93LC]

Just for kicks I tried installing the cdl switch mod. Hooked it up to a hazard light switch for testing. I did not do the "7 pin mod" shown in the video I watched because I was not quite sure what was shown in the video. When in either 4l or 4h, the switch had no effect at all. Is this because I didn't do the 7 pin mod, or does it help point to the initial problem?

 

[clivehorridge]

As a matter of interest Aaron, how do you know it's not working?

Whenever I select low, (or the dash CDL switch in high) I've never noticed any click or whir.

Neither do I hear the rear locker engage, when I select that. The front locker does make a faint click, but that's about it.

Only the front locker indicator light shows engaged (on my 80) the rear doesn't, even though I know it is engaged.

I'm just wondering how you're so certain the CDL isn't working?

 

[Chris]

Forget the pin 7 thing. We're struggling to work out why the Americans are so fond of it. Wheat it does as far as we can see is this:
Your auto box has set gear change intervals. When you do the dash switch mod the change intervals sort of change when in low range. This makes low range driving nice and sensible. If you do the pin 7 mod, what it effectively does is restore the original change intervals back for low range which are ghastly. Clearly on a manual, there is no pin 7 mod.

I'd forget the dash switch mod for now. Get it working as it should to start with. You haven't said if you have checked all the connectors underneath yet.

 

[clivehorridge]

 

[Aaron93LC]

The ABS light does not come on, the CDL light does not come on. The only reason I was asking about the pin 7 thing is because that's what the video mentioned. Personally. if it's not needed then I won't bother. Several of the articles I read mentioned turning the key to the on position and shifting into 4L would result in a audible noise as the CDL engaged.

As to the sensors, no, I have not checked them yet. That's my next step, probably should have been my first one.

As to me being an American, do me a favor and don't think of me that way. I'm just a guy who bought a Land Cruiser and wants to learn how to make it work properly. My geographical location has nothing to do with that. Personally, I'd rather be a Jamaican. I can't help where I was born. =)

 

[Towpack]

Do the DL warning lights on the dash light momentarily when you turn on the ignition before starting the engine? When I do as you have described, ie, turn on the ignition and lock the CD I can hear the actuator operate. This also goes for the front and rear actuators. If you get no lights at startup and the fuses are OK I'd check the plug connector at the diff lock ECU first behind the LH kick panel.

 

[Chris]

Ha Ha, the comment about Americans was in no way meant to be derogatory. It's a fact. We do the switch mod and so do other countries, but only in the US do they seem to be fixated with the pin 7 mod. We can't understand why anyone does it. It brings the horrid gear changes back again.

Typically the whole middle locker set up tends to be incredibly reliable. People do have issues at times and we have learned that it really pays to check out the basics such 'as is it plugged in?' before we get into changing ECUs etc.

 

[Aaron93LC]

Chris, I didn't take it as derogatory, my only point is that I want to do what's best for the truck, not what the "hot" thing to do is in my country. Here the majority of LC's seem to be street queens, so if it's popular here, but not in countries with more experience, than logic says I should not do it!

Towpack, I don't get any actuator noise at all. I don't remember if the lights came on, I'll check them in the morning. It's a bit chilly out to be messing with it tonight. If they don't come on, I'll get start checking connectors and cleaning out any muck I find.

Thanks for both of your help!

 

[Aaron93LC]

I HAVE FORWARD PROGRESS!!!! =) Well, some anyhow. I removed the drivers footrest and the 4WD computer, uncoupled the connectors, blew in them like an old Nintendo game cartridge and hooked them pack up. Then I wiggled all the other connectors I could reach to reseat them and dropped it into 4L. Right away I heard the clicks from the foot well. I swapped out my emergency flasher switch to the manual CDL plug and tried that. Worked right away. Having a gravel driveway, I confirmed with a short drive and turning the wheel that the CDL was engaged. That's the progress......
.....BUT.....
When the CDL engages the ABS light does NOT turn on, and the diff lock light does not come on. The front and rear locker still do not engage. The lights come on and flash but no more. I'm going to take the short drive down to the beach and see if the will engage where I have a little more room to maneuver, but I have a feeling that I have a bad sensor connection somewhere.

 

[Chris]

It's odd and unusually common electrical failure from Mr T but the lock sensors do fail. They are a simple ball bearing spring plunger affair but if they don't work then the 4x4 ECU won't go to the next stage (ie rear then front lockers) So yes the two options are that A it's not locked or B it is but not detected. Sounds like B. Simulating isn't difficult. Just short the contacts on the sensor probe. Having checked that it's connected in the first place, naturally.

 

[Aaron93LC]

That's my next step! I've heard that sometimes they have to be manually worked in and out to unstick them from lack of use. I'll check to make sure everything is hooked up, but I just had to take the truck to the beach to see how it compared to the '78 Suburban I had been driving. Guess what? It doesn't, not at all. Like apples and oranges. Even when I took the Cruiser out onto the sugar sand and parked it with street pressure in the tires, then accelerated.... it still behaved like it was on pavement. Just pulled away like I was leaving a shop! Of course, the rest of you probably already knew that. So.... Suburban, lot's of thunder and size but the Cruiser won that comparison hands down. I really wish I had found this thing years ago!