rear diff lock problems on jtop not engaging

[jonnyjtop]

my diff lock was working perfectly now all of a sudden it wont engage i put it in 4x4 with the c/d locked like normal but when i try to engage the r/d lock it wont do anything i used to hear the little pump go and it would click in i know the switch is working because when i push it the diff light starts to flash are there any cmmon probs with them or any fuses i can check its a jap import so everything is written in jap on the fuse box any imput would be apreciated...thx guys i dont want to pull the car apart if i dnt have to so hoping its a common prob and a quick fix

[WACKO]

if your not hearing the compressor going id start there. its in the left hand backseat side panel. pull it out and put power to it.

Sam

[jonnyjtop]

sorry i forgot to add i did put permanent power to the compressor and it worked fine ill have to pull it apart and check the little computer and all that then..

[WACKO]

so when you hit the button, you hear nothing but the light on the dash flashes. and if you put power to the compressor directly it starts pumping like it should?

do you know anyone else with a jtop or factory locker in theirs that you could borrow the computor out of to try in yours?

[jonnyjtop]

na unfortumately my mates are all toyota boys ill probably pull out all that computer and stuff tomorrow and take a propper look its not majorly important but i just thought there might be a fuse or somethin that could make it easier...because it looks like that whole pannel will have to come off that means removing the roof by the looks of it because the bolts go through it if the computer is no good do you think it would be ok to bypass the computer put permanent power to it with a normal switch? or should i source another one...?

thanks heaps

jonathan...

[WACKO]

you dont have to remove the panel, but it ends up being faster as its such a pain in the butt with it still there, and yes you do have to remove the roof. there is a way of hard wiring them up without the comp, but im not sure how. it also bypasses the having to be in 4wd bit aswell.

have you checked your diff oil? you should change it.if lots of little small squareish biits of metal fall out, no amount of looking at your computor will help.

[jonnyjtop]

yeah i pulled it all off yesterday it all looks fine checked all fuses and all was good the diff works perfectly when i put permanent power to it but still cant get the bastard to work woth the switch i spraed electrical contact cleaner on all the bits ect all seems to be connected well no corroded parts ect yeah i changed the diff oil already about a week ago no metal came out...yeah i already know how to wire it without having to be in 4wd and its really fun on loose/wet roads!!!hahaha but just want it to work properly from the switch it hasent been working since my mecchannic last changed the clutch but since then i myself have replaced the box with new switches on it ect and made sure all wired up properly...i have the flashing 4x4 syndrome but i doubt its that because it still worked fine up until a few weeks ago,... its just bugging me on how it can just stop working...im usually pretty good with these things i even managed to get my crappy electronic dampners working...but not this

[Ian Sharpe]

Have you checked the dash switch itself, ?? they are about $80 new I think. They are a latch type setup.

You dont really need the factory ECU etc. If all else fails you could pick up an active from the ignition somewhere & get a hold of a latch relay & do it that way.

Thats what I did, & I am now using the ARB switches which I like becuuse they are a nice blue colour & they have nice little pics on them & they are heaps cheaper than the Mitsu switch!.

[jonnyjtop]

hi ian do you mean the switch where its on the dash or is there another thing behind inside the dash if you mean the switch itself meaning the one that you phisically press yeah iv inspected it and tested it it all works fine im going to try trace the wires all the way next and see if there is any breakiges if that fails im off to buy a switch that i can just send direct power to it wether its in 4x4 or not...one thing i forgot to do was put a test light to the wires on the pump itself and see if any power was going to it...
sorry for sounding stupid but i know what a relay is but what do you mean by latch type relay... im sure its something simple...

did you just run a wire from the rear pump to the front switch and pick up a positive and run a new switch??

is there supposed to be positive power going to the origional switch because i tested all of them and none of them run positive power???if so why does the middle light still flash telling me iv pressed the switch.. if there is no powe??

[Ian Sharpe]

JT,
A latch relay is a 2-coil, 2-position relay. The coil activation of one coil will
transfer the armature and contacts to the other position. Conversely, activation of the other coil will transfer the armature and contacts back to its original position.

It relies on pulse type activation, you can buy latch relays at Repcos , I have seen them there. You will only need this if you decide to use the original switch, but do check out the ARB switches , they are nice, but any old on off switch will do.

The locker ECU is there basically to limit use of the locker, it drops it out if you go over 12kph, it only allows operation in 4WD Low, etc , just basic stuff about protecting the locker itself. You really dont need it but if you by pass it you have to remeber that the locker can be operated in any condition at any speed, even scooting along the highway at 100kph if you accidently knock the switch on. I have mine wired up using the ARB diff lock switches & the locker switches only operate if the compressor switch is on & this only operates if another switch is on as well (on the dash), so whislt it is possible to accidently operate the locker, it has been reduced by using a couple of other switches as well. It depends upon how safe you want to be!.
As you say there might be a broken wire in your circuit somewhere or the ECU might be stuffed. I'm not sure how much a new one would be , but IMO it wont be cheap, you could be lucky in finding one at a wrecker, but this stuff is prett hard to find, took me 18mths to find my 2nd hand locker.!


See this post long ago about wiring
http://www.outerlimits4x4.com/viewtopic.php?t=26709

If you still want to retain the light that comes on the dash display when the locker is on (orange) then you have to identify the active for that & re route power to it using your new configuration. The easiest way IMO is to take out the dash & trace the printed circuit on the back of the dash to identify the wire which turns the light on, cut that wire before the connector & join to your new active. The light is activated by a switch actually inside the diff & not by the pump operation switch because it is possible for the locker to be unlocked/locked even when the pump is on/off. The wiring for the switch in the diff can be accessed by tapping into the connector wires that come out of of the diff housing.

I know all this sounds like a lot of mucking around, but unless you can really identify the cause of your problem, I dont think you have much choice
cheers

[hudson44]

It sounds like it's buggered. I'll give you a perfectly good LSD for your "broken" locker, LH axle and compressor......Sounds fair to me!

[jonnyjtop]

yeah hudson sounds like a good swap to me! hahaha...

ian thnks for your imput its been helpful and reassuring that i will not stuff anything rewireing it i will have one last look on the weekend then if i cant figure it out ill be putting on a regular switch or drop into a arb store to make it work... ill probably just use any old switch (ill probably also use two) as it wont be worth it for me to start buying new ecu units ect and stuffing around...

many thanks once again...that link helped too

jonathan..

[pom300]

did you make sure all the wires on top off the gearbox were done properly when you changed it there should of been 5 little dome like solenoids on the top of yours check them out and there is a electrical wire underneath above the diff i think that has something to do with the locker
give those ones a check,it only takes one dumb thing to come out or a loose wire for the whole lot to stop workin.

[jonnyjtop]

yeah pom iv checked and cleaned all of them...it ws not working from before i changed my box i was hoping tht when i replaced the box with the new one it would start working again but it diddent...i think iv traced the problem down to the little computer thing that is next to the pump itself they may have blown as i have run permanent power to before to run it in 2wd with a locker and my guess is that something has probably shorted it out...ill just run it on a normal switch it was bothering me but ill get used to it