75ZT Community

raistlin wrote:Would T/C of this type be required in a Freelander Duncan?

To be honest, no idea.

Hi guys

Been doing some more investigating (like everyone on this) today & am certain that Duncan is spot on (no suprise really). The T/C system works by either applying the brakes or lowering engine revs, not transfering power from wheel to wheel as in more modern systems.

As Duncan says there are 2 part numbers involved, one for the control unit (sticker on black plastic) & the only numbers that acctualy matter are the 0 265 900 004 (same with the similar number stamped into the milled face on the unit) & It is only the LAST 3 digits that really matter as the rest are common to a lot of Bosch parts.

The system, well the engine revs part, is CANBUS controled so to my mind the thoughts on either Rob not having the full wiring (as his is a facelift) or a fault in the Canbus to IPK (Instrument pack (IPK from the German)) comunication could be the issue.

As mine, like Paul's, is a MK1, i'm going to do some checking re my wiring. Could be useful to know what you have/had Paul if its possible.

There is a similar system fitted to some 7/5 & X5 series BMWs which again share some things with the Freelander & this is where Bosch are getting the 1.8 thing from i think. With a bit of luck i'll get some confirmation tomorrow when i've spoken to them.

Regards

Paul

Hi again guys sherlock here.

Having spent more time on the phone to Bosch Technical this morning i have good news...!!!! (well maybee not for Rob).

The ABS (Antilock Braking System)/TC Pumps/Modulators we have are right for a 75 Diesel with traction control. The confusion arises from part number supersession/development/deletion. The one part of the item, the metal block is for the Rover but the other part, control unit (plastic) is used by other manufacturers vehicles.

They have no way of telling if the parts are working without sending them to them for testing (costly i should think) so we can only assume they are.!!!

Unfortunatly they say that the issue with Robs car is more than likely Canbus related, which could be either missing or faulty wiring as the Traction part of the control unit is unable to talk to the ECU (Engine Control Unit) & tell it to reduce engine revs (the way the diesel T/C works).

So it's down to wiring diagram checking Rob or worst case senario ECU problem (do they all suport T/C)(or does it have to be changed?) or worked on alah Re-Map.

Regards

Paul

Magic post Paul thanks for your efforts

I have looked at the RAVE wiring diagrams for TC and it appears that a wire goes from pin 35 of ABS ECU direct to pin 22 of the ECM, maybe thats the next thing to check, but before i get the battery box out yet again, would just like to get opinions of Duncan and Paul to see if they agree that pin 35 is next to be checked and if there is anything else to check whilst I have access.

Hi, Rob. I think that wire (Red/Blue) is the speed signal and will be there on all cars. Worth checking, though.

While in there, check the CAN (Bus Controller Area Network) wiring. Yellow Brown to pin 40, yellow black to pin 24 in the ABS. You can only really check for if they are there or not. If you wanted to you could check for continuity, but you would need to pull out something like the instrument pack and check to the same colour wires there. The wires will be a pair, twisted together. I'm beginning to think it's got to be something odd like these being missing. Funny though if the TC switch wiring is there.

Rob/Duncan

Been giving this a lot more thought (my head is hurting more than ever), Whilst it is possible that there could be a wiring fault (ECU/Canbus) could it be that there is a problem somewhere with the ABS actuator ring (just a bit of muck) as this also has some bearing on the Traction Control.

Totaly left field i know but could it also be a faulty TC switch if it was a used one?

Sorry if the above are stupid things to say, just trying to help.

Regards

Paul

Not the switch Paul as swopped it for Pauls to check and still not working

Have a look and see if the CANBUS wiring is there Rob. If not we can hopefully install it quite quickly.

As I understand it, that wiring can be connected into the bus anywhere.

Trebor wrote:Not the switch Paul as swopped it for Pauls to check and still not working

Ok Rob, was just a thought.

Looks more & more Like Canbus wiring then mate.

Regards

Paul

Paul D, I can't see it being a wheel sensor, as the ABS light goes out and there's no fault codes in the ABS. I'm not confident it will be the wiring as I'd expect a fault code in the ABS for that, if traction were coded. Got to be worth a check, though as we are out of ideas otherwise.

Will check asap guys, been a hectic week with a grandchild arriving and only came home today, plus will be at the Classic car show on Friday which was booked well in advance and i thought i might have to cancel it at one stage

Might look at the IPK wiring first as might be quicker but need to study the wiring diagrams first

Rob, the IPK wiring will be there, otherwise you would have bigger problems. It's just where you could find another end of the ones that should be in the ABS unit.

Duncan wrote:Rob, the IPK wiring will be there, otherwise you would have bigger problems. It's just where you could find another end of the ones that should be in the ABS unit.

Could they be spliced into a known good part of the Bus if required Duncan? I'm assuming it is a genuine databus.

Yes, its a genuine databus. 2 wire differential. Yes it could be spliced anywhere, within reason. Just get the low and high the right way round.

Duncan wrote:Yes, its a genuine databus. 2 wire differential. Yes it could be spliced anywhere, within reason. Just get the low and high the right way round.

That would be helpful. because if we can't trace the other end of the databus wires from the ABS, we could hopefully splice in somewhere upstream, as it were.

In the same way, if there are no wires there, and we have the correct contacts we could do the same N'est-ce pas?

Luckily, the connectors aren't coaxial, as is the case with databus on military aircraft They can be an almighty PITA to terminate

I feel somewhat guilty and responsible for this as I said to Rob, in passing, "Why not fit traction control mate - it's a doddle." Well... it was with VeeKay

If the databus wires are in the ABS, then it's simplest to find the break. I think the splice is in the wheelarch.

ok Guys thanks, i will hopefully check the ABS end at the weekend then,and Paul please dont feel guilty as i have learned a lot more about the car by doing this and its certainly a challenge which is never a bad thing and at least my car is working fine without TC being activated

Have to agree with Rob.

It was reading your posts Paul about fitting the traction that prompted me to go for it BUT as Rob says i've learnt so much more about the cars & the way they work since all this started (also made a good contact at Bosch), so no guilt Paul, none at all. Do feel sorry for Rob though as it isn't turning out easy for him which is why i've stayed involved & will do so untill the bitter end. (when i've done mine) Lol.

It would appear that missing wiring is more common on facelifts as i've a mate in Rugby who wants to chance manual to electric seats & theres no wiring in his facelift, not even the heated seat plugs so its down to making up looms (joy).

Heads down & onward...!!!!

Regards

Paul

The only thing I'd say, is early cars are by far the worst for missing wiring. My Cowley car had NOTHING at all. Not even the wiring for heated washer jets. When fitting Nav, I had to add wires from the ABS into the cab. No cruise wiring, no seat wiring, no blind wiring. Need I continue?

I've been dead lucky with VeeKay then. All the looms have been in place.

NOT that a simple thing like a missing loom would have stopped me