ECM Swap
 

First post but advice appreciated from any guru's who might have a suggestion about a non starting diesel '02 Conn SE Tourer, before a trip to testbook!

The Story
Bought myself a diesel '02 plate Conn SE Tourer which had suffered from a small fire on the Glow Plug which had caused the main wiring loom to melt an completely wreck the ECM. There was also some mild damage to the bonnet where the heat had removed the paint. Apart from that the rest of the car was in fine condition. OK so a bit mad to but fancied a project to work on, and end up with a great car! (Current car Rover 600 SLi). I suspect that the blocked drains below the ECU allowed water to collect around the ECU and causing the short which started the fire but not known for sure.

Then i bought a breaking '05 plate conn SE Tourer so have all the bits and wiring i could need including the ECM to repair the original car. The donor car would start but had severe underbody damage and was a salvage car.

pic 1 = see first pic of the damaged ECM removed from the original car

What I did next

Ok so I had 2 cars, - all the bits i'd need to make 1 working car. I got to work and Stripped the ECM and engine wiring from the donor car. Decided to cut the wiring loom below the BCM in the passanger footwell to solder in the same position on the new car. Taking the car to bits was quite straightforward and i soon had all the bits i thought i'd need.

Looking in more main car, the Air / Climate unit had melted from the heat and needed replacing - another item to take from the donor car. By this point i had the dash out.

Pic 2 = interior of the car with dash removed

Also decided there were some other "bits" on the donor car i fancied.

1. Rear Park Sensors
2. Facelift Front Bumber and lights
3. Diming rear view mirror with auto rain sensing wipers
4. Message center and computer
5. Cruise Control
6. Facelift rear bumper

Happy to give an overview of the above swaps if anyone is interested.

Pic 3 = new car with face lift bumper from donor car - different colours! (note spot the fire damage at top of bonnet)

(I would have also like to have taken sat nav but sadly neither car had this, so maybe a project for next year if i can get the bits cheap enough on eBay!)

Got most of the external body work swapped and the car was beginning to look good....... time to tackle the engine wiring......

Replacing the ECM
After removing the damged wiring i refitted the new loom and soldered the 40+ wires together under the passanger footwell.

Pic 4 = joined wiring looms

Fitted the BCM from the donor car, the new instrument pack, a bit of fiddling with the light control box to retain the front fogs which the original car had but the donor car didn't. As far as i was concerned the original car had the full electronics from the donor car.

• BCM
• Light Control Box
• Keys - internal transponder and sender unit from the fob

Connected the car up and turned the key - was looking good .... internal electrics fired into life, message center working all OK turned the key to start the car and nothing apart from a nice message saying engine disabled.

OK i'd missed the imobilisation ECU (EWS3) from the donor car and the transponder in the key obviously no longer matched the original Immobilisation ECU, and was preventing the starter motor from coming to life. Swapped the immobilisation ECU from the donor car.

Engine now cranks but still fails to start so the transponer in the key and the immobilisation ECU now match.

Fault Diagnosis

OK checked loads of posts (mainly on here - thanks for the great info) and came up with a plan:

1. Check with easy start

Yes engine fires ok until easy start is consumed .... causing the rev counter to increase - diagnosed a lack of fuel to the engine on crank.

(warning don't use too much easy start - it can lock the engine for a bit and takes a while to get it to the point where it will crank again)

2. Check fuel is available

I wouldn't recommend doing this but i loosened the fuel pipe into the engine and fuel was ejected when the key was turned so thus available in the common rail.

3. Replace CAM and Crank sensors

4. Check fuel pumps

Internal fuel pump could be heard running however the in tank one at the rear of the car could not (although it was getting a feed when checked with a test light). I removed this and even when powered directly wouldn't run.
As i'd read a lot of posts about the rear fuel pump causing starting problems i was hopefull this was the cause of my problems.

pic 5 = the dead fuel tank pump

New fuel pump added and could now be heard running when the ignition was started .... Pressure was definately higher now on the fuel rail.
.... Great i thought, however the moment of truth .... on trying to start the engine, the engine cranks yet still fails to start.......

What's the problem?

I checked the injectors with a volt meter and they are not getting 12V from the ECM when trying to start. I suspect the following:

1. Security is preventing the car from starting
e.g. Rolling code on the imobilisation ECU and engine ECM are out of sync

2. Wiring is different between the '02 and 05' model

3. I've failed to solder the wiring loom correctly

4. Something else!!!

Other Pointers i discovered along the way
If the headlights lights flash on starting, and the engine fails to crank there is a lack of charge in the battery.

So any ideas of what else could be causing the engine to fail to start? Advice appreciated before it goes on test book!

:welcome: to the Club Iain.
Certainly done a lot of work there well done.
Some of our experts will on later to help you more with suggestions.
The lights flashing when turning over is generally a Classic Duff battery,
but if you have been turning over a lot could now just be flat.
I am pretty sure that the Main ECU, BCU etc have to be matched so the whole lot should have been swapped over preventing a lot of problems but may still need "matching" on T4. as it appears engine still on Immobilised.
Not an Auto by any chance?
Has to be in Park to start or Neutral, might sound silly but it has happened before.

Nope its a manual .... although an auto would have been nice!

Everything should now be matched - theoretically all the electronics are from the donor car ....

The only new thing i noticed was a sensor on the pipe near the EGR valve ..

My couple of weeks project has now turned into a couple of months! A pic of the rear with new rear bumber with PDC, and new tailgate section.

Just a further thought,
did/do you have the internal alarm sensors on either car?
They require a different Alarm Unit.
I also take it that you changed the Glo Plugs to?
You may have to wait till morning for someone that has played around in this area.
Sorry can't be of more help, you have done all the normal things for non starting but it does as you say sound as if could be linked with the Immobiliser/coding.

Thanks for the tips - i'm not sure about the different alarm sensors so i'll have a look next time i'm up at the car ... i think the Alarm and the immobilisation work differently .... not had a problem with the alarm / locking so am assuming that if the BCM and the key match then all is OK for the alarm.

The original white box for the glow pugs (sits near the ECM in the engine bay) was toast from the original fire so that's been changed ....

Another point to note the Engine fault light is constanly on in the instrument pack, however when i had the codes read with a generic OBD reader it showed an error with the fan and lack of earth (next problem to move on to when i've fixed the starting problem!). I don't think the guy who read the codes really knew what he was doing - he tried to re-program the key, but that stopped the remote locking from working at the time (yet another problem to look at later). The symtoms still remain the same.

The only other errors were "security timeout" which i guess was a result of the key being removed and resetting the immobiliser at the time, and something about the throttle sensor being our of range. Neither of which i think should have prevented the car from starting with the correct key transponder.

I think the throttle error may have been due to the only wire which i hadn't soldered as the colours didn't match - was Red / Green on the new wiring loom and Red / Slate in the original. All the others matched.

Iain,

Forget the part of my
PM that asks how your project is doing:lol:

Good luck, sounds like you are so close...............

Dave...

Don't forget the Maf sensor,
Disconnect to see if it will start.
They play up a lot or may just need cleaning:
http://www.the75andztclub.co.uk/foru...ight=clean+MAF
If it is faulty get a Replacent from Rover Ron (ad at top of page) cheaper and more reliable than the XPart one.
You would also need his Mafam or get a Synergy which ups the Power etc at same time.

OK i'll give that a try - i think when i get it running i'll have a look at upgrades and maybe the roverron gizzmo - would be got to get it to running first though!

If the engine cranks, then the immobiliser is happy with the key. But it's possible the engine isn't happy with the code from the immo.
Maybe a problem caused by the attempted starts with the wrong immo unit.

I don't think anything other than key transponder, imoo box and engine ECU have to match to start the engine. The BCM only uses the key to unlock the car an operate the alarm.

You won't get much help from a scantool. They usually only read emissions related faults. I think a testbook session is in order.

Just thought I would say that is some project you have taken on, well done!

I think a T4 session might help as a starting point but you may be looking at a fair bit of fault finding as well which if you get a dealer to do will cost you a lot of money.