4WD dash lights

[beachcomber]

Please can somebody explain the correct 4WD light sequence on a 3rd Gen?

I assumed 4 steady greens in 4WD only (H2H4 position) plus a steady orange if diff locked (H4L). Flashing lights as 4WD engages/disengages.

At the moment, if I push the 4WD button, lever in H2H4 position (to the left left and forward), all 5 lights flash continuously. I can feel 4WD engage (steering heavier) but steering winds-up on lock as though centre diff is engaged.

Should the 4 corner greens/centre orange be steady-on or flashing when 4WD engaged?

Methinks I have a problem!!! Any ideas very, very welcome.

[stormforce]

Please can somebody explain the correct 4WD light sequence on a 3rd Gen?

I assumed 4 steady greens in 4WD only (H2H4 position) plus a steady orange if diff locked (H4L). Flashing lights as 4WD engages/disengages.

At the moment, if I push the 4WD button, lever in H2H4 position (to the left left and forward), all 5 lights flash continuously. I can feel 4WD engage (steering heavier) but steering winds-up on lock as though centre diff is engaged.

Should the 4 corner greens/centre orange be steady-on or flashing when 4WD engaged?

Methinks I have a problem!!! Any ideas very, very welcome.

have a read thru here...http://www.hiluxsurf.co.uk/forums/sh...ad.php?t=16281
and here...Hilux Surf FAQ at www.hiluxsurf.eu

[beachcomber]

Many thanks Richard for prompt reply.
I have read the threads and I understand the issues with the time required to disengage 4WD.

My concern is the centre diff. In the H2H4 position, the centre diff should not lock - I would not expect to see the orange centre light at all when selecting 4WD, only the 4 corner greens. But the steering is definitely winding up - the diff is definitely locking; and all 5 lights continued to flash, even after 4/5 kms.

If I disengage 4WD the lights eventually go off, but at no time do they become "steady".

?????

[stormforce]

Many thanks Richard for prompt reply.
I have read the threads and I understand the issues with the time required to disengage 4WD.

My concern is the centre diff. In the H2H4 position, the centre diff should not lock - I would not expect to see the orange centre light at all when selecting 4WD, only the 4 corner greens. But the steering is definitely winding up - the diff is definitely locking; and all 5 lights continued to flash, even after 4/5 kms.

If I disengage 4WD the lights eventually go off, but at no time do they become "steady".

?????

Hi i only have a 2nd gen so i don't know anything about the 3rd gen's but someone will be around and let you know what you need to know shortly i would think

[TonyN]

Flashing orange and green lights are its 'selecting' warning, they flash even when switching from H2 to H4, but orange goes out when the green 'wheel' lights stay on and it has selected properly.

When in H4L or L4L the orange light should be on continusly, along with the green lights.

If it continues flashing after a minute or so its a fault, and can't select properly, try reversing on either lock to get ti to select, if not used much it sometimes takes a while to sort itself out.

[beachcomber]

Many thanks Tony. Guess (hope!) I've just got a sticking problem. I'll take it out and thrash it around a bit to try and free the mechanism.

Quick question - are the bits that are sticking internal to the boxes or somewhere externally where they can be lubricated?

HNY

Don

[beachcomber]

Hi,
Quick update.
Eventually got the lights to stop flashing and only the corner greens steady (i.e. 2H4H - 4WD with cent. diff. unlocked). Tony's tip of reverse on lock worked (thanks again, Tony).
Diff. will not unlock unless I do this, but I hope it will free up with a few more goes at it.

My conclusion is - pushing the 4WD button (in 2H4H) does two things:
1) Engages 4WD
2) Disengages cent. diff. lock.
In my case, (1) was happening, (2) was not - which is why the lights did not stop flashing.

This assumes the centre diff. is locked in normal 2WD and needs to unlock for 4WD. Is this correct? - or has my wagon a fault here? Is it normal for the front centre diff. to be locked in normal 2WD?

If I can sort the corrrect normal operation and sequence of events, may help someone else in the future.

Thanks all. Looking forward to replies.

Don

[Rob]

I've noticed the centre diff thing you're describing. I was trying to put it in 4WD the other week by pressing the button only. I happened to be turning on full lock in a car park at the time. Next thing I knew was that my inside rear wheel was scrubbing and skipping the tarmac, whilst all the lights were flashing. Seems like the 4WD system temporarily locks the centre diff whilst engaging 4WD.
I don't think the diff is usually locked when in 2WD as the front propshaft would always be turning (which it doesn't). It did take a few backwards/forwards movements to unwind and release the 4WD back to normal after this. I guess that's why the instructions always say "only engage 4WD when all wheels are turning at the same speed"....
I don't think you've got a proper fault which is good!

I'm guessing the process goes something like this:
1) Centre diff locks to bring stationary front prop and diff up to speed (assuming you're 'shifting on the fly').
2) ADD system at the front engages drive to the front wheels.
3) Centre diff releases

Cheers,
Rob

[beachcomber]

Hi Rob,
Thanks for your reply. I totally agree with your sequence of events.
In my case, (1) and (2) are happening (diff. locks and 4WD engages) but the diff. does not disengage. I have to reverse, shuffling lock to lock to get the orange light to go out and the greens to go steady.
It sounds like the diff solenoid (???) moves one way OK to engage the diff. but sticks and will not release after the ADD system brings in 4WD.

If I disengage 4WD, all 5 lights will flash "forever". Need to perform the reversing procedure to disengage! How long does it take for your 4WD to engage/disengage under normal circumstances?

Can you help with the location of the diff. solenoid? Do you know if it is accessible to be cleaned/serviced?

Also, you quote from a manual! I did not get any documentation with my Surf. Is this something you obtained in the UK and if so, would you let me know your source.

Many thanks for your help.

Cheers,
Don

[ash-ssrg]

Am experiencing much of the same as described by Beachcomber but still have the flashing lights. Difference is that (1) not sure if my truck 4wd is engaging in the front diff (ADD) and (2) the rear diff locks but does not unlock after I hit the 4wd switch. Rear diff does unlock after I disengage the 4wd switch though.

I bought mine in Nov 2006 with the problem already in place. Previous owner admitted to NEVER using 4wd.

Trouble is I am not getting the time to look at or even use my Surf at the minute.

Anyway - bottom line is that I want to let you guys know: YOU ARE NOT ALONE.

Ash.

ps: makes sense but can anyone confirm ROB's point no.3 in the previous post?

[beachcomber]

Hi Ash,
Thanks for your input.

Not sure what you mean when you refer to the "rear diff."

Please see the following link. It explains the 2WD/4WD/Diff. setup.

http://www.offroaders.com/info/tech-...eading/4wd.htm

I think you have the same problem as me - the centre diff. not unlocking.

The way the vehicle drives should tell you what is and what is not engaged.
- 4WD will have a noticeable effect on the way the vehicle handles
- if the centre diff. is also locked, you will feel the steering stiffening as you turn the steering wheel and the tyres will scrub. BEWARE - IN THIS SITUATION YOU ARE WINDING UP THE TRANSMISSION AND SOMETHING WILL BREAK!

Determined to fix this!

Cheers
Don

[ash-ssrg]

Sorry - I meant the centre diff - not rear.

Thanks for the article though, just finished reading it! I think our problems are slightly different though. My centre diff locks and unlocks at the flick of the 4wd switch which yours doesn't.

My prob is the front Diff ADD thats not engaging.

But at least now I know why the steering tightens when the 4wd switch is on and that it is not (I hope) part of my problem. CHEERS.

PS: Beachcomber Don - The father-out-law was in Texas and brought us back a CD of the american 3rd gens repair manual in pdf format. Some of the stuff in not applicable but I will search for info on the centre diff solenoid and forward it on if I have it.

Ash

[beachcomber]

Many thanks Ash - look forward to seeing the info on the solenoid.

One thing though - you say you are not engaging 4WD. If I understand the system correctly (and that may not be the case!!) the steering will only tighten if in 4WD. If the ADD sleeve has not engaged 4WD, the front wheels are free-running independently and will not wind up the transmission to cause the tightening.

Anyone else help here???

Cheers,
Don

[Rob]

Hi Don,

My 4wd only takes a few seconds to go engage or disengage. It definitely won't go if the drivetrain is under load - ie when you're accelerating. At other times, if it doesn't go straight way, ie in a couple of seconds, i just blip the throttle then release totally. This causes all of the drivetrain components to be unloaded for a moment, allowing the system to enagage/disengage. This is all when driving forward in a straight line by the way. When stationary I might have to go forwards and backwards slightly, or just a gearchange from D to R and back to D again usually does it.

Fortunately (for me), I've never had to mess about with 4wd system so my knowledge isn't great...
There's a vaccuum operated actuator on the front diff (pain to get to). This is connected to some vaccuum switching valves (VSVs) on top of the passenger front wing in the engine bay, sort of under the air filter housing. It would be worth checking none of the vacuum hoses are split or perishing.
I think the centre diff is operated electrically, and I don't know much about it. There's about 3 or 4 wiring connectors to it though, so again it might be worth checking all the connections are good and aren't causing an intermittent fault.

Hehe, I wasn't quoting from any specific manual - its just that many 4wd cars' instructions say it. Having said that I got a translated manual from http://www.car-handbooks.com/Surf.html . They're published by JPNZ (www.jpnz.co.nz). I think they're good for what they are - a basic handbook. Try a search for handbooks or manuals on the forum - they're available from other places too, possibly cheaper.

One other thing I just thought of, although I'm not sure how long you've had the problem, but... Are all your tyres exactly the same size and all the same pressure? I guess its possible that if a tyre wasn't the same diameter as the others it could cause some slight windup - enough to stop the 4wd working smoothly....just a thought.

Cheers,
Rob

Hi Rob,
Thanks for your reply. I totally agree with your sequence of events.
In my case, (1) and (2) are happening (diff. locks and 4WD engages) but the diff. does not disengage. I have to reverse, shuffling lock to lock to get the orange light to go out and the greens to go steady.
It sounds like the diff solenoid (???) moves one way OK to engage the diff. but sticks and will not release after the ADD system brings in 4WD.

If I disengage 4WD, all 5 lights will flash "forever". Need to perform the reversing procedure to disengage! How long does it take for your 4WD to engage/disengage under normal circumstances?

Can you help with the location of the diff. solenoid? Do you know if it is accessible to be cleaned/serviced?

Also, you quote from a manual! I did not get any documentation with my Surf. Is this something you obtained in the UK and if so, would you let me know your source.

Many thanks for your help.

Cheers,
Don

[beachcomber]

Thanks Rob. All 4 tyres new, so must presume wheels turning in synch.

I'm now convinced my problem is with the centre diff. not unlocking when going 2WD to 4WD or from 4WD to 2WD. In both cases, green and amber lights never stop flashing.

Diff. obviously locks at some time (to bring the front prop up to speed??), 4WD cuts in, but centre diff. doesn't unlock to complete the procedure. If I move stick to 4HL lights stop flashing immediately confirming the truck is in 4WD and the centre diff. locked.
If I go back to 2H4H and disengage 4WD, again centre diff. doesn't unlock; lights flash on and on.

I can unlock diff. eventually, but have to do double backflips, in reverse with triple somersaults to make it happen!!!

Can anyone please tell me the mechanism for locking/unlocking the centre diff.? Is it vacumn controlled or an electrical solenoid, and if the latter, where is it located? Can I remove it to clean or degunge or whatever it needs?
Any procedures, pics or advice gratefully welcome.

many thanks
Don