CCU & immobiliser - 1999 L-series

Back again with the never-ending Freelander saga!

A while ago I posted about rear door and central locking issues, and the 3 Amigos. I eventually sorted the ABS so decided to get it Mot'd (back door not required). Went through the usual checks and found that the foglights didn't work. Checked them out and everything was OK other than them not switching on. Another thing controlled by the CCU. Opened it up and found various tracks corroded.

Fitted 2nd hand CCU and matching fob.

Central locking - cured!
Dash CDL button working for the first time!
Tailgate opens and closes!
Foglights work!

But it doesn't start. Or even turn over. The immobiliser light goes out. Relay on the fuse board clicks when I turn the key to start And thats it. No power makes it's way to the solenoid. To make matters worse, I put the original back in and that does the same (plus the original faults).

My understanding is that on the early models it's only the CCU that is coded. not the ECU. The fact that the original doesn't work now either points to me having pulled a wire somewhere, but having had it in and out several times I'm damned if I can see where. Can anyone tell me which wire should be going live (or to earth) when i turn the key to start? The way it's parked changing the CCU was OK -getting in upside down with a torch and a meter is something else again.....

Any pointers gratefully received

Dave

You need to pair the CCU to the ECU so that it will enable starting - have you done this?

This can be done via decent diagnostic kit like T4/Autologic/Hawkeye etc

The CCU will inhibit cranking - but that is easily fixed by routing the earth from the starter relay to ground rather than the CCU.

However, the ECU will probably then not fuel the injectors and that is harder to fix. It is not impossible and is just a few wires - but I'm not sure what they are. I've seen a Freelander ECU plugged into a Rover 620 and the engine started and ran (although not properly due to different pump or TPS I believe) - but the ECU ran without being connected to the CCU.

So the ECU is coded then? I had hoped to prove that by refitting the original CCU, but when that didn't work either......

Anyone around Grantham with the above mentioned kit reading this??

td4van said:

You need to pair the CCU to the ECU so that it will enable starting - have you done this?

This can be done via decent diagnostic kit like T4/Autologic/Hawkeye etc

Click to expand...

Can used ECUs and CCUs be paired by comms kit? I thought that would be the case with new kit but not used - ie once paired they can not be changed.

If that were the case, could they not just have the immobilisation switched off - ie as the Japanese setup.

I gained the impression that all the immobilisation was done within the CCU - as long as you had the matching remote no reprog. was required.

Dave _O said:

I gained the impression that all the immobilisation was done within the CCU - as long as you had the matching remote no reprog. was required.

Click to expand...

As far as I know, engine immobiliser function is done by the immobiliser module, which receives a code from the remote fob, via the CCU. The CCU does the locking/ unlocking, and acts as the code gateway for the alarm/ immobiliser ECU. If the engine ECU doesn't get the correct fob run code from the immobiliser module, the engine won't start or run.
It might run if you enter the emergency access code, via the door lock.

Nodge68 said:

As far as I know, engine immobiliser function is done by the immobiliser module, which receives a code from the remote fob, via the CCU. The CCU does the locking/ unlocking, and acts as the code gateway for the alarm/ immobiliser ECU. If the engine ECU doesn't get the correct fob run code from the immobiliser module, the engine won't start or run.
It might run if you enter the emergency access code, via the door lock.

Click to expand...

I thought the CCU WAS the immo module on the early cars......

Can Hawkeye reprog. this? The new Total jobby isn't too much - or are thy just diagnostic?

Dave _O said:

I thought the CCU WAS the immo module on the early cars...

Click to expand...

No. The CCU does the door locking and passes the code on to the immobilizer (5AS unit IIRC) ECU. The immobilizer ECU then communicates the run code to the engine ECU. If the codes don't match, then the engine won't run.

Dave _O said:

Can Hawkeye reprog. this?

Click to expand...

I don't know. It's normally a job for T4.

No separate immobiliser ecu on a Freelander 1 - it’s all integral to the CCU.

The CCU sends the coded message to the engine ECU to release the immobiliser.

When you fit a different CCU then you need to resynch to the Engine ECU. On the cars with immobilisation in the CCU I believe that you can change the CCU and resynch to the existing Engine ECU on the car.

With EWS and later JLR immobiliser systems you need to fit a matched set (brand new immobiliser is preprogrammed to match engine ECU) or a brand new engine ecu can be learnt to the existing immobiliser or a complete set of keys, immobiliser, engine ecu as a minimum depending on vehicle