Centre Diff lock vs Traction control

[wagon boy Member Find all posts View Profile Close wagon boy]

Hi guys,

I picked up my first Prado (5ps auto, V6 Grande 120) on monday and have been playing around with it a little bit, and have noticed that the centre diff lock doesn't seem to be activating. I've spent the last couple of days reading through every post on here with regards to that and am aware that it's seems to be (somewhat) common for the unit to have problems.

Two questions:

1) when the ignition is switched to 'on', every other light on the dash comes on, but not that, is that normal?

2) after hours of reading and using the search function, I see that a lot of people have a problem with the system at some point, whether its the switch or the actuator itself, but I haven't found anyone mention whether or not traction control will still be a useful aide if I go offroad. I was hoping to take it up the beach this weekend (I haven't been offroad since I decided to sell my 'lux, and am aching for it), but I do not want to do this if i'm likely to get completely stuck with a one wheel drive! Will traction control still send power to the rear wheels/front wheels as necessary if the centre diff lock isn't engaged?

Thanks in advance!

[Guest Close Guest]

What have you tried so far to get the CDL to work?

I don't think I would venture onto the beach with CDL not engaging. The traction control may not work instantly by which time, you might be bogged already.

[wagon boy Member Find all posts View Profile Close wagon boy]

Pressing the button repeatedly. And firmly.

I tried pressing it and driving up a dirt road for a while, then in reverse, then forwards again, but that's it so far. I won't have too much time to pull things apart before this weekend, but wondering if it's 'safe' to take onto the beach (will have another couple of vehicles with me). I'm hoping it's just the switch, when I press the DAC switch, it click in and out, but the CDL switch doesn't, it always returns to the same position.

Does your dash indicator light up on startup?

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

To put things in a bit of perspective, did your Lux have traction control or a centre diff lock? If not then whats the difference now?

The centre diff lock helps but I drive in soft sand often without engaging it. I don't have traction control but my understanding is tat it's best turned off in sand.

Remember the Prado is constant 4wd.

Cheers Andrew

[wagon boy Member Find all posts View Profile Close wagon boy]

Thanks Andrew,

No my lux was a 2004 model (last of the good ones ) so no Traction control, and only part time 4wd. So I guess in short, everything is different! before I just had to get out and lock the hubs in, press a button on the stick and off she went.

My reason for concern was that I saw someone in one of the other threads mention that he had buried a wheel in mud and been stopped because of it. i.e. the centre diff wasn't sending any power to the rear. I don't actually see a switch for the traction control, and I even read the manual in search of it! I believe that when I turn the CDL on, the VSC is shut down...

THanks,

Brodie.

P.S, thanks for your email, am compiling my list of desires so I can get some bits off you soon.

[Guest Close Guest]

The CDL button is a momentary switch. So it will return to the same position every time.

When I turn on the ignition, the CDL light does no come on.

When I press the CDL button, the CDL light will flash and you can hear the actuator trying to engage the diff. Once it clicks in, the CDL light stays on. The VSC light comes on as soon as the CDL button was first pressed.

[wagon boy Member Find all posts View Profile Close wagon boy]

OK so it appear then that the switch isn't performing. When I press it, I get no response at all from the car, so I'll start there.

Any suggestions for quickest way to access that part of the dash? I've seen someone said that they removed a panel in the pass footwell and squeezed their hands in, and another pic shows someone removed the gearstick shroud. It's so neat and 'finished' compared to the lux that I'm afraid to yank on stuff.

Oh, this is the thread I was referring to with one wheel stuck in mud.
http://www.pradopoint.com/showthread...+lock+spinning

[wagon boy Member Find all posts View Profile Close wagon boy]

And thank you both for your help! I appreciate your time.

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

There have been a couple of instances of this and if memory serves the problem came down to the connectors on the actuator. So I would remove these, give them a good spray with WD40 and make sure the connectors are clean.

With the 120 with TC control you really need to lock the centre diff for soft sand so it switches off the stability control. You will get bogged otherwise. As a wheel spins the brakes are applied and the power reduced.

[wagon boy Member Find all posts View Profile Close wagon boy]

Hmm ok. Yeh I found a few threads referring to the connectors, and just as many with switches; I'm hoping it's the easier options first . Looks like I'll have to skip the beach and spend some time in the garage instead!

The prado has never been off road, and I am confident the CDL has never been activated. (I purchased it off a mates dad who's decided to get a 200)

Thanks again.

[kav Avid PP Poster! Find all posts View Profile Close kav]

You shouldn't have any problems either way , the traction control can be over ridden by the use of the right foot . Not sure why the CDl doesn't light up . Make sure your driving in a straight line when engaging. Check that all the rear lights are working . If you have a trailer electrical connector , flush it out with wd40 and try again. Your new prado grande is going to eat your old lux for breakfast anywhere anytime in ultimate comfort .

[Pradolot Junior Member Find all posts View Profile Close Pradolot]

Vsc tc and ctr diff lock

This is my understanding and how mine works
Vehicle stability control... Is a function operation at all times on the grande unless centre diff lock is engaged. What it does is cuts the power/revs to engine if going around a corner to quick and you start to drift. Eg. On a flat dirt paddock if you try do a doughnut from stand still. You'll go about 3 meters before stability control say to computer ...He's going to fast and drops revs to around 500rpm..
Centre diff lock.... As grandes are already constant all wheel drive this button lets the transfer case transfer a 50/50 ratio to front and rear tyres instead of the usual 70% rear 30% front of there abouts. When centre diff lock is engaged the also disables the vehicle stability control. So effectively to can go back to the paddock and do 4 wheel doughnuts
Traction control... This is also on all the time, when one tyre on opposing side of diff spins at a certain rate faster than the other... What if will do is engage the abs module and brake the tire with least resistance. So if your in a wombat hole and one wheel is off the ground the car will automatically brake that wheel this sending all the power to the wheel on the ground.
Note this ratio between opposite wheels spinning unequally is also atleast 2-3/1. So the wheel off the ground will spin a few times around before t/c is engaged and it brakes that wheel.
So to answer your question.. If you were going to go on the beach it would be fine until you had to turn a corner. Because without the centre diff lock the vsc would still be active and it would cut your revs. This would happen in examples like trying to turn off the beach back onto main track. Another thing if be worried about is if you actually did get stuck. The traction control wouldn't know what to do.. So it would brake one wheel. Dig a hole. Brake other side. Dig a hole. Ect ect until you've sunk to your chassis. Hope this all makes Sence
Mullins

[wagon boy Member Find all posts View Profile Close wagon boy]

Well I couldn't help it, I had to get out there tonight and figure out what was wrong. I started by cleaning the plugs on the case - no change, and starting to get dark, so decided to allow a tiny bit more time.

Decided to start playing around in the dash, and that's where the embarrassment occurs... So the vehicle has an electric brake controller that was fitted by my mates dad. In the process he had removed that part of the dash, and all the plugs and switches related. And evidently forgot to plug one back in - the CDL switch :-/

It works fine. Hmmmm, I feel like a proper fool now.

A massive thanks to everyone for your help and advice, I think I might hide for a little while ops:

Thanks!!

[wagon boy Member Find all posts View Profile Close wagon boy]

Vsc tc and ctr diff lock

This is my understanding and how mine works
Vehicle stability control... Is a function operation at all times on the grande unless centre diff lock is engaged. What it does is cuts the power/revs to engine if going around a corner to quick and you start to drift. Eg. On a flat dirt paddock if you try do a doughnut from stand still. You'll go about 3 meters before stability control say to computer ...He's going to fast and drops revs to around 500rpm..
Centre diff lock.... As grandes are already constant all wheel drive this button lets the transfer case transfer a 50/50 ratio to front and rear tyres instead of the usual 70% rear 30% front of there abouts. When centre diff lock is engaged the also disables the vehicle stability control. So effectively to can go back to the paddock and do 4 wheel doughnuts
Traction control... This is also on all the time, when one tyre on opposing side of diff spins at a certain rate faster than the other... What if will do is engage the abs module and brake the tire with least resistance. So if your in a wombat hole and one wheel is off the ground the car will automatically brake that wheel this sending all the power to the wheel on the ground.
Note this ratio between opposite wheels spinning unequally is also atleast 2-3/1. So the wheel off the ground will spin a few times around before t/c is engaged and it brakes that wheel.
So to answer your question.. If you were going to go on the beach it would be fine until you had to turn a corner. Because without the centre diff lock the vsc would still be active and it would cut your revs. This would happen in examples like trying to turn off the beach back onto main track. Another thing if be worried about is if you actually did get stuck. The traction control wouldn't know what to do.. So it would brake one wheel. Dig a hole. Brake other side. Dig a hole. Ect ect until you've sunk to your chassis. Hope this all makes Sence
Mullins

Thanks heaps for explaining this all to me, I've already learnt so much from this forum, I can't wait until I can (hopefully) contribute something back

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

No need to feel foolish. It's fixed now, time for a trip to the beach!