For the starter inhibit in gears other than Park and Neutral, the V6 uses a white wire from the auto box to the Immob ECU.

Now, the Immob ECU prevents cranking when the ignition key chip is incorrect too and also requires a key chip match to the Immob ECU and the Engine ECU.

Have you retained the key chip and Immob ECU as originally designed or bypassed any of it?

Just wondering if any mods have eliminated the Immob ECUs ability to prevent cranking. It does this by breaking the feed to the starter relay.

I guess the white wire provides a feed or 0V only when in Neutral or Park, If this is true then an additional relay in the starter relay path controlled by this wire would solve the problem.
I just had ten minutes spare to check this. I put a voltmeter on the white wire that you mentioned and ignition off it's 0V and ignition on it's 12V, irrespective of where the gear lever is. So I have messed up something.

The immo and key chip is unmodified, present, and it's the original K series one.
 
I'm pretty happy with this:-
Screenshot83.png

Screenshot84.png
 
The circuit diagram says
Fuse 35 to header 0292 to the inhibit switch to C0067-7 behind the radio to the immo

Screenshot86.png
 
Doh, I was probing on the wrong side of the inhibitor switch. When I probe on C0067-7 I'm getting 12V in P or N, and 0v in any other position, but the immo is still ignoring that and letting me start in any gear
 
looking at live data from the Immo, there is a parameter called "In gear"
Screenshot88.png


It isn't changing whatever I do with the gear selector. I think they must be coded to manual or auto.
 
I haven't reported on progress for a while. I have been mad busy making progress.......

The exhaust is now extended, on and seems to work well.
The cooling system is now finished, but I have a leak somewhere on the back of the engine. I'm suspecting that the metal cross pipe to the water pump joint didn't survive removal / refitting.
I have spent most of this week finishing the transmission wiring.
I wasted nearly a day because Jatco ECU and all of the associated bits were powering up with ignition on, but remaining powered up when the ignition is turned off.
This is because I am powering the gearbox and ECU from the "main relay" which is actually controlled by the engine ECU, and it keeps that main relay powered for upto 15 minutes after engine shutdown for "emissions reasons" such the purge valve.
Anyway, I went back to the Rover 75 wiring diagrams and that's exactly how the gearbox ECU on an auto 75 is powered (it stays powered on with the emissions stuff).
I still need to wire in my own custom cooling fan controller and a Rover 75 A/C trinary switch.
I have one wiring problem left which is that the Auto ECU is supposed to be able to suppress the starter motor. It does this with a wire from the Jatco ECU to the immobiliser, but that isn't working (it will start in any gear). My suspicion is that the autos must have a different config on the immobiliser ECU, which I'm not going to touch, so I will have to "proxy" the starter motor wire through my own relay off of the Jatco output.
The engine runs quite nicely, but with some subtle but odd noises.
There is a bit of an odd scraping noise from the accessory / timing belt end above 2000rpm which I need to fault find.
The gearbox sometimes makes odd gurgling noises after startup, which I assume is air trapped somewhere it shouldn't be.
I also have an intermittent misfire on one cylinder.
Apart from the starter issue, that you look to have covered having proved the voltage in the wire can control a relay, you look to be down to 'regular' mechanical issues.

Pretty good position to have got yourself into :cool:
 
It isn't changing whatever I do with the gear selector. I think they must be coded to manual or auto.

But the gearbox feed isn't changing so the immobiliser ecu won't do either.

Check you have both sides of the gearbox inhibit switch wired OK. Looks like one side is ground and the other to the immobiliser ecu.
 
But the gearbox feed isn't changing so the immobiliser ecu won't do either.

Check you have both sides of the gearbox inhibit switch wired OK. Looks like one side is ground and the other to the immobiliser ecu.
Yes it is changing. 12v in P or N, 0V in other positions. I was probing with a voltmeter in the wrong place.
 
I'm just a few days from being able to drive this, though I don't like a noise coming from the transmission.
Anyone got any ideas where to get modified car insurance for this?
I tried Greenlight insurance but they wouldn't even give us a quote.
 
I didn't sleep much last night as I was thinking about the noise from my transmission.

So, in this scenario:-
Engine running
In D or R
Foot on brake, so wheels not turning

I think because it's in gear and the wheels are not turning, then most of the transmission also isn't turning.
My understanding is that in this scenario that the only parts turning are the flexplate, torque converter and oil pump?

So if it makes a noise in gear but wheels not turning then that rules out most of the transmission?

Or have I misunderstood something?
 
I didn't sleep much last night as I was thinking about the noise from my transmission.

So, in this scenario:-
Engine running
In D or R
Foot on brake, so wheels not turning

I think because it's in gear and the wheels are not turning, then most of the transmission also isn't turning.
My understanding is that in this scenario that the only parts turning are the flexplate, torque converter and oil pump?

So if it makes a noise in gear but wheels not turning then that rules out most of the transmission?

Or have I misunderstood something?
Turn the radio down?

Sorry - I’ll get my coat.
 
also, Hill Descent no longer works. I press the button and put the transmission in 1 or R, and nothing happens.

Looking at circuit diagrams from the original 1.8 there is a first gear switch (not now connected at all) and a reverse switch (now replaced with relay that the automatic stuff triggers). These switches go into the instrument cluster.

So I get that it won't work in first gear right now, but it should work in reverse, but it doesn't.

My suspicion is that the stock 1.8 cluster stops processing those switch inputs when it starts getting CanBUS data from an auto gearbox ECU. The cluster is displaying the gear selected. Maybe I will need to fit that auto instrument cluster after all.
 
actually, I just tried it on our TD4, and Hill Descent is supposed to start flashing as soon as you press the button, and then it goes solid once either the 1st or R switches close.

But I'm not longer even getting the flashing green Hill Descent light, so, either my Hill Descent button is no longer working, or, the presence of the Jatco CANbus messages has put the cluster into a different, non Hill Descent capable mode.
 
I'm just a few days from being able to drive this, though I don't like a noise coming from the transmission.
Anyone got any ideas where to get modified car insurance for this?
I tried Greenlight insurance but they wouldn't even give us a quote.
I believe a popular insurer for modified vehicles used to be Adrian Flux...


IIRC they used to be a sponsor on LZ.

Can't help with the noise. Do you know all the donor parts were OK?
 
First drive, and according to my friend who was driving (because he has trade insurance to drive anything), it drives very, very nicely:-

 
Well done. Sounds great.


What about the keep you up at night noises in the gearbox 🤔
If I knew which part is causing the noise, I would change it. It has to be either the oil pump or the torque converter. I don't really want a bad part to spread metal through an otherwise good gearbox.
 

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