75ZT Community

I am in the (slow) process of Fitting cruise to a CDTi. Steering wheel controls = done. Dash switch = done. Now i am waiting for the cruise ECU (Engine Control Unit) to arrive from Xpart. When it does, and i am trying to find it's plug, and connect it to my system, do I need to disconnect the battery? If so, anyone know why? ??

Oh, and will it need a t4 to connect it all up properly afterwards?

Thanks..
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Technically it will need a T4 (Testbook version 4.Computer Diagnostic System) session to enable or let it know one is fitted,
but
people that have fitted Cruise seemed to have it working without the T4,
so try first.

Safety first is the normal thing for electrics and ECU's.
Some don't bother others swear by it, to prevent shorts on new ECU either remove fuse for power to system or disconnect.
(I am sure others will have different views on last statement)

Unless you know everything about a specific circuit, I'd suggest it would be worthwhile popping the fuse out. It only takes seconds

Thanks John. I dunno where the fuse lives raistlin, but can take a lead off the battery no prob.
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Without a T4 it will work, but not in the normal way.

Switch on at the dash: green light as normal.

Then you use the lower switch on the steering wheel and the yellow light comes on, at any speed. Obviously speed isn't maintained. Pressing the top button sets your speed, pressing the lower cancels it. Resume doesn't work at all. And if you press the lower button when it's not holding speed, the yellow light goes out and you have to switch off then back on at the dash.

Regarding battery off. It's the safest way with anything, to power down the whole car. I have to admit generally I don't bother, except for some airbag type work.

Thanks Duncan.
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plus you can accelerate for up to about 30 secs , and after it will resume the last set speed.
Everything else as Duncan says..
TBH.. having used it for some while ,the resume function which needs the T4 session to setup is not much of an omission in our sort of traffic.

just pretend RES means reset "

I have cruise fitted which was fitted as an after market one. It was fitted by the previous owner. Do you think I'd be able to move the controls to the steering wheel buttons or is it best left as they are on a stalk abover the indicator stalk?

ardvark wrote:I have cruise fitted which was fitted as an after market one. It was fitted by the previous owner. Do you think I'd be able to move the controls to the steering wheel buttons or is it best left as they are on a stalk abover the indicator stalk?

I see no reason why you shouldn't, at least in theory. A lot depends upon the type of controls, ie. whether they are simple switches or a resistor ladder, for example. You would, in my view, need to investigate how the switches actually work before deciding whether it was a worthwhile exercise

As far as I can recall, but stand to be corrected, the OEM controls are just straightforward switches.

I rang Xpart, and they tell me that the ECU has been posted so I should receive it on Monday (tomorrow) so fingers crossed I can report back then with all the problems plugging that in will cause.. heh heh..
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James.uk wrote:I am in the (slow) process of Fitting cruise to a CDTi. Steering wheel controls = done. Dash switch = done. Now i am waiting for the cruise ECU to arrive from Xpart. When it does, and i am trying to find it's plug, and connect it to my system, do I need to disconnect the battery? If so, anyone know why? ??

Oh, and will it need a t4 to connect it all up properly afterwards?

Thanks..
...

Hi James,

Am I correct in thinking that you have the steering wheel controls? If not I have one that you can have.

Cheers

Mike

Thanks for the kind offer Mike, but i have already fitted the steering wheel controls.

In fact -- My cruise is now working!! YAYYYY Undid the lil panel under the glove box, found the lil plug, plugged the ECU interface in, and it now works!!!

I will need a T4 to get the "resume" to work but apart from that it's all unky dory..
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James.uk wrote:I will need a T4 to get the "resume" to work but apart from that it's all unky dory..
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A very good reason to turn up at the nano-meet James

Pleased to hear you got it working

James.uk wrote:Thanks for the kind offer Mike, but i have already fitted the steering wheel controls.

In fact -- My cruise is now working!! YAYYYY Undid the lil panel under the glove box, found the lil plug, plugged the ECU interface in, and it now works!!!

I will need a T4 to get the "resume" to work but apart from that it's all unky dory..
...

Excellant ! I hope you will join us on the Cheshire convoy to the Wolves nano-meet on 22nd August. Think a T4 will be in attendance to get you CC fully operational.

Cheers

Mike the banned

Regarding the T4, before you get Toooooo excited.

It's not an individual option on the T4 to switch on and off. You will need to get a complete new ZCS calculated. This can be done but you need to be aware that there is a vague possibility of it going pear shaped. I'd talk to David (Monk) in advance to make sure you are happy.

I intend to do the same, but haven't done it yet, so can't say if it worked on mine.

Duncan wrote:Regarding the T4, before you get Toooooo excited.

It's not an individual option on the T4 to switch on and off. You will need to get a complete new ZCS calculated. This can be done but you need to be aware that there is a vague possibility of it going pear shaped. I'd talk to David (Monk) in advance to make sure you are happy.

I intend to do the same, but haven't done it yet, so can't say if it worked on mine.

Quite correct Duncan.

I'll be doing this to mine too when I get chance.

New codes and their checksums can be calculated, but they aren't easy to apply to the car.

The car has to be "tricked" into requesting the codes be entred into the car manually on T4, if on writing the code a malfunction occurs then there is a distinct possibility that the car will no longer work.
Even if the code is entered and sucessfully written then depending on the age of the car certain functions may no longer work.

For these reasons all work of this type is carried out at the owners own risk.

Russ

Well I guess I can live without the "resume" button working. It's simply not worth the risk.

My thanks to Duncan and Russ for the timely warnings.

I think that's me finished with mods to my car. It now has pretty well all I need.
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er yes forgot about that........... Yellow Peril told me that you need to confuse the T4........ or something like that.

So pleased that VeeKay had cruise control from new then

I hate it when electrickery bits don't work precisely as they should - must be a phobia

Rover418275 wrote:er yes forgot about that........... Yellow Peril told me that you need to confuse the T4........ or something like that.

Yes, you have to let it see bits from two different cars, and it can't decide which one is right, so asks you to enter the correct details. There's a bit more to it, but that's the outline.