Disco 2 Difflock help please

Hi
I have a 01 plate Disco Td5 Automatic and am getting a new higher ratio trans box due to taller tyres.
Now I am also looking at having a centre diff lock fitted to the new box but can people tell me if when i select cdl will this disable traction control and abs ??, as looking around on the internet some say yes and some say no.
Also i have found something that says that you need to have the engine switched of before selecting cdl and that if you switch of the engine with cdl engaged you have to reengage it when you restart the engine ??, this makes no sense to me what's so ever as the cdl is cable operated so how can switching off affect this ??.
All suggestions gratefully received.
Thanks Bill.

Hi, the 01 modell should have the early ABS ECU which inhibits the TC if the central diff is locked when the ignition is turned on. If you lock de diff with engine running the TC remains active which in some cases can be good in others bad. The newer ECUs were upprated to make the TC work together with CDL all the time.

To answer that too

Billybones said:

Also i have found something that says that you need to have the engine switched of before selecting cdl and that if you switch of the engine with cdl engaged you have to reengage it when you restart the engine ??, this makes no sense to me what's so ever as the cdl is cable operated so how can switching off affect this ??.

Click to expand...

Because the ECU is making a system self test when the ignition is turned on and verifies all the inputs then, if it finds the CDL engaged it switches to that mode when the TC is disabled, while the engine is running the system keeps working based on the inputs from the ignition self test and neglects the CDL input. In the description the ignition self test thing is missing you'l have to trust me on that

Hi
Thanks for your input, but how does the slabs ecu know the difflock is engaged ?? as there seems to be no wire connector attached to it (the difflock unit) or am i missing something ??
Bill

Yes, you are missing two things:
1. the SLABS ECU's pinout description from the WSM where it's clearely visible that C0506 pin 9 is "Centre differential lock switch - Input"
2. there is a "diff lock switch" on the trasfer box which closes to earth when the diff is locked and sends this signal to the ECU and to the instrument pack for the warning lamp.... shown with blue arrow, there are wires connected to it

Basically if you are getting a lower(lower, i assume, not higher) transfercase from a defender, if it is a td5 model it will probably have the diff lock switch in place and you just need to hook to the loom under the center console. If it is from an older defender it might not have it so you either need to drill and tap a switch (messy, need to clean it properly) or put a manual switch so that you can manually tell the ecu diff lock is engaged and tc can work accordingly

Hi
sierrafery thanks for the picture, have spoke to the trans box supplier and they have confirmed the switch for difflock light is there but they are not sure if the vehicle wiring is there or where to find it, might have to wire a idiot light in, although they have also suggested that i use the g/box temp switch wires and swop them over in the binnacle to light up the difflock image,
Mad85, no its not a defender box but a new discovery one with a different ratio, 1.2 is standard for disco and 1.41 is standard for defender, i am going for 1.301 which i have been advised will bring me back to near factory given my new tyre height.
Bill

Billybones said:

have spoke to the trans box supplier and they have confirmed the switch for difflock light is there but they are not sure if the vehicle wiring is there or where to find it, might have to wire a idiot light in, although they have also suggested that i use the g/box temp switch wires and swop them over in the binnacle to light up the difflock image,

Click to expand...

Usually the later facelift modells are missing the CDL switch wiring but if your's doesnt have it the g/box temp switch wiring is OK just that the connections have to be done at the connector under the console not at the binnacle otherwise the signal can miss the SLABS ECU

Thanks for that, mine is a pre facelift 2001 so hopefully the wiring will be there, i do have the symbol on the dash but don't know if there is a bulb behind it, next thing i need to do is find out what colour the wires are and then take out the cubby box to see if i can find them, if so i can bridge across them to see if the light illuminates, if not then plan B use the the g/box temp switch as you suggested.
Bill.

The original CDL input wire at the box should be black/blue wire with spade connector and a black one which is earth, if you dont find those wires there you'll have to run a wire from the CDL switch to C0668(male)/0681(female) pin 7 (also black/blue wire) which is there for sure in the male side, if you find unconnected black/light green wire at the box you can use that on the switch, cut the wire at C0668 pin 4 and splice into pin 7 with it, the other side of the switch must be connected to earth

Hi
Thanks for your explanation and picture, if i read you right there are three options.
1) There will be a blue/black and a black wire somewhere by the trans box made for the job.
2) Run a new wire from the cdl switch to the blue/black wire at pin 7 on the male side
3) Use the unconnected black/light green wire if its there, (what would this have been used for ??).

If i have to use option 3 what was pin 4 used for and is it o.k not to have it connected to anything ??, it seems like options 1 & 2 are the best bets.
Sorry for all the questions but i just need to understand what i'm doing.
Bill.

The BU(black/blue) wire if it's there it is the original CDL switch input, the BLG(black/light green) wire is the transfer box temp warning input which used to be there unconnected, it was used only for NAS automatic modells but part of the loom so LR didnt get rid of it in all cases... watch the electric diagrams, if you can read them you'll understand but if you can't understand a diagram then better believe me "in blind`"

Thank you for making it clear, helpful as usual.