engine ems (ECU)

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RRkev

Active Member
Posts
430
Location
Forest of Dean, Gloucestershire
hi guys hopefully someone with a bit of tech knowledge can help me, my current rangie is a 2003 4.4v8 with the bmw engine,

my main engine ecu has gone faulty, so looking at options i bought a used ecu from my local land rover breaker, took it to my local indy who tried to reprogram the imobiliser code but couldn't through the diagnostic port so gave me a few options, a new one from lr costing £858 plus vat, bba reman or a guy called mark adams. on contacting bba reman they would only repair my exsisting unit and took upto 10days to do, using my car for work it wasn't an option really so i contacted mark adams really nice guy knows his stuff!.

so here is the nitty gritty i sent both ecu's to mark who has cloned my original unit into the used unit that i bought, he noticed although the used part i bought was newer it only had a revision 2 board in it whilst my current one has a revision 3 both part numbers & ecu numbers were the same, but everything looked the same pretty much, he also noticed although the used unit was from a 2004 l322, the software was completley different to the software in my car, so he's reflashed the correct software into the used ecu. on getting this back this morning i plugged the reprogrammed ecu into the car and tried to start it, it turns over but won't fire so guessing it's the imobiliser code kicking in.
so my questions are

1. is the imobiliser code stored in the ecu? (mark did mention it could be in the bcu) hence why after trying to reprogram the new unit, when my original was put back on also had to be reprogrammed to the car.
2. would the different software prevent the ecu from being reprogrammed before, long shot i know but got to ask.
3. if the code is stored inside the engine ecu does anybody know where it s stored? (mark did also mention the same ecu is used on a few other cars and the code is written to the cpu on some)
any help appreciated.

cheers all
 
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Where are you?

What made you think your engine ecu if faulty?

What diagnostics did your indi use?

Not come across this before on a L322 on a p38 the engine sync is from the BeCm same for a GEMS or a Motronic so I am assuming same for you as its a security issue. In your hand book is there a security code you can programme via your plip in your door?

But you may need T4 Testbook and would assume that a replacement ecu can be configured as I do occasionally do on p38s especially motronic ones (I have done this for my car just to have it as a spare - you do need the correct ecu, after configuration I sync the security code and the car should start.) In fact T4 gave the option of updating the software which I did. I think you need proper diagnostic to configure it to your car.

Configuration is important as there are variations in car spec etc.
 
Last edited:
Fram RAVE (Sorry about the formatting!!)

Immobilisation System
The immobilisation system is a transparent system that prevents unauthorised starting of the vehicle by providing a
secure interface between the ignition switch and the Engine Control Module (ECM). It also prevents the engine from
starting if the steering lock is engaged or if the gearbox is not in park or neutral.
The immobilisation system consists of:
l The transponder in each ignition key
l The transponder coil around the ignition switch
l The immobilisation ECU
Transponder
A transponder, consisting of a wireless Electronic Erasable Programmable Read Only Memory (EEPROM), is
incorporated into the head of each ignition key, including the 'wallet' ignition key. A password and key code in the
transponder provides each ignition key with a unique identification. As a further security measure, the transponder
contains a rolling code number written to it from the immobilisation ECU. The transponder key code and rolling code
are entirely separate from the remote handset codes.
The transponder is written to and read from by the immobilisation ECU via the transponder coil. The maximum range
for communication between the transponder and the transponder coil is approximately 20 mm (0.8 in).
Transponder Coil
The transponder coil is installed around the top of the ignition switch key barrel to enable communication between the
immobilisation ECU and the ignition key transponder. To operate the transponder the immobilisation ECU energises
the transponder coil with a 125 kHz ac current. This energises the transponder by electromagnetic induction.
Amplitude modulation is used to write data to the transponder.
CAUTION: The drive for the transponder coil is not capable of carrying battery voltage and care must be taken
when fault finding and probing the system otherwise permanent damage to the immobilisation ECU may
result.
Immobilisation ECU
The immobilisation ECU is installed on the driver's side of the gear selector assembly, underneath the centre console.
When it detects a valid transponder/ignition key in the ignition switch and is receiving a release signal from the steering
lock ECU, the immobilisation ECU sends a release signal to the ECM and energises the starter solenoid when the
ignition switch is turned to crank. The release signal to the ECM is a further rolling coded synchronised in the
immobilisation ECU and the ECM. If either the ECM or the immobilisation ECU are replaced they have to be re-synchronised
using TestBook/T4.
Up to 10 different transponders can be used with the immobilisation ECU. The 10 unique transponder key codes and
their associated rolling codes are generated during vehicle production and programmed into the immobilisation ECU.
The transponder of each ignition key supplied with the vehicle is then programmed with one of the key codes and its
associated rolling code. Once the immobilisation ECU and the transponders have been programmed they cannot be
over written. The 'spare' key codes and associated rolling codes are retained in the immobilisation ECU for future use.
The key codes and associated rolling codes are also recorded in a spares support database together with the Vehicle
Identification Number (VIN).
If an ignition key is lost, the key code of the related transponder should be disabled in the immobilisation ECU using
TestBook/T4. If the key is subsequently found, the transponder can be enabled again.

If a replacement or additional ignition key is ordered, the transponder of the new ignition key is programmed by the
spares supplier with one of the spare key codes and associated rolling code from the spares support database. The
immobilisation ECU recognizes the first use of the key code and automatically enables the new ignition key.
When a replacement immobilisation ECU is ordered it comes pre-programmed with the key codes and rolling codes
from the spares support database ready for use with the existing ignition keys once it has been synchronised with the
ECM.
A starter motor protection function is incorporated into immobilisation ECU. When the engine speed exceeds a
predetermined value, a relay inside the immobilisation ECU is disabled. This prevents damage to the starter motor in
the event of a sticking ignition switch or if crank is selected while the engine is running.
The immobilisation ECU is powered by a permanent battery feed from the passenger compartment fusebox. It also
receives an auxiliary power feed from the passenger compartment fusebox and a crank power feed direct from the
ignition switch. A connection with the K bus provides the immobilisation ECU with engine speed and locking system
status.
 
Where are you?

What made you think your engine ecu if faulty?

What diagnostics did your indi use?

Not come across this before on a L322 on a p38 the engine sync is from the BeCm same for a GEMS or a Motronic so I am assuming same for you as its a security issue. In your hand book is there a security code you can programme via your plip in your door?

But you may need T4 Testbook and would assume that a replacement ecu can be configured as I do occasionally do on p38s especially motronic ones (I have done this for my car just to have it as a spare - you do need the correct ecu, after configuration I sync the security code and the car should start.) In fact T4 gave the option of updating the software which I did. I think you need proper diagnostic to configure it to your car.

Configuration is important as there are variations in car spec etc.

i've had a engine failsafe mode for a few weeks, after going through everything including testing the wiring i could not find a fault, i then one day tested the wiring warm and found shorts between throttle and thermostat circuits, just as i was about to rewire both systems i did a test with the ecu disconnected and the shorts did not exsist, plugged in a borrowed ecu and no shorts in the wiring, reconnected my original and shorts came back. this was also apparent after my indie tried to reprogram used ecu and couldn't but then it took 5 times to get my exsisting ecu to recode to the car. my indie uses autologic for coding, fault reading etc, he can usually do earlier cars but said mine is just late enough to be a write once unit. oh and i'm in gloucestershire uk
 
Last edited:
Fram RAVE (Sorry about the formatting!!)

Immobilisation System
The immobilisation system is a transparent system that prevents unauthorised starting of the vehicle by providing a
secure interface between the ignition switch and the Engine Control Module (ECM). It also prevents the engine from
starting if the steering lock is engaged or if the gearbox is not in park or neutral.
The immobilisation system consists of:
l The transponder in each ignition key
l The transponder coil around the ignition switch
l The immobilisation ECU
Transponder
A transponder, consisting of a wireless Electronic Erasable Programmable Read Only Memory (EEPROM), is
incorporated into the head of each ignition key, including the 'wallet' ignition key. A password and key code in the
transponder provides each ignition key with a unique identification. As a further security measure, the transponder
contains a rolling code number written to it from the immobilisation ECU. The transponder key code and rolling code
are entirely separate from the remote handset codes.
The transponder is written to and read from by the immobilisation ECU via the transponder coil. The maximum range
for communication between the transponder and the transponder coil is approximately 20 mm (0.8 in).
Transponder Coil
The transponder coil is installed around the top of the ignition switch key barrel to enable communication between the
immobilisation ECU and the ignition key transponder. To operate the transponder the immobilisation ECU energises
the transponder coil with a 125 kHz ac current. This energises the transponder by electromagnetic induction.
Amplitude modulation is used to write data to the transponder.
CAUTION: The drive for the transponder coil is not capable of carrying battery voltage and care must be taken
when fault finding and probing the system otherwise permanent damage to the immobilisation ECU may
result.
Immobilisation ECU
The immobilisation ECU is installed on the driver's side of the gear selector assembly, underneath the centre console.
When it detects a valid transponder/ignition key in the ignition switch and is receiving a release signal from the steering
lock ECU, the immobilisation ECU sends a release signal to the ECM and energises the starter solenoid when the
ignition switch is turned to crank. The release signal to the ECM is a further rolling coded synchronised in the
immobilisation ECU and the ECM. If either the ECM or the immobilisation ECU are replaced they have to be re-synchronised
using TestBook/T4.
Up to 10 different transponders can be used with the immobilisation ECU. The 10 unique transponder key codes and
their associated rolling codes are generated during vehicle production and programmed into the immobilisation ECU.
The transponder of each ignition key supplied with the vehicle is then programmed with one of the key codes and its
associated rolling code. Once the immobilisation ECU and the transponders have been programmed they cannot be
over written. The 'spare' key codes and associated rolling codes are retained in the immobilisation ECU for future use.
The key codes and associated rolling codes are also recorded in a spares support database together with the Vehicle
Identification Number (VIN).
If an ignition key is lost, the key code of the related transponder should be disabled in the immobilisation ECU using
TestBook/T4. If the key is subsequently found, the transponder can be enabled again.

If a replacement or additional ignition key is ordered, the transponder of the new ignition key is programmed by the
spares supplier with one of the spare key codes and associated rolling code from the spares support database. The
immobilisation ECU recognizes the first use of the key code and automatically enables the new ignition key.
When a replacement immobilisation ECU is ordered it comes pre-programmed with the key codes and rolling codes
from the spares support database ready for use with the existing ignition keys once it has been synchronised with the
ECM.
A starter motor protection function is incorporated into immobilisation ECU. When the engine speed exceeds a
predetermined value, a relay inside the immobilisation ECU is disabled. This prevents damage to the starter motor in
the event of a sticking ignition switch or if crank is selected while the engine is running.
The immobilisation ECU is powered by a permanent battery feed from the passenger compartment fusebox. It also
receives an auxiliary power feed from the passenger compartment fusebox and a crank power feed direct from the
ignition switch. A connection with the K bus provides the immobilisation ECU with engine speed and locking system
status.

Thanks saint my indie uses autologic for programming but could not reprogram the used ecu i bought because it was already coded previously to another vehicle, hence why i got the clone done, this will allow the car to crank but not fire so must be some more coding in the unit somewhere. i have found out searching the web that to recode a previously used unit it has to be done direct to the eprom not through the diagnostic port, this is pointing towards a new lr unit at the moment.
 
Thanks saint my indie uses autologic for programming but could not reprogram the used ecu i bought because it was already coded previously to another vehicle, hence why i got the clone done, this will allow the car to crank but not fire so must be some more coding in the unit somewhere. i have found out searching the web that to recode a previously used unit it has to be done direct to the eprom not through the diagnostic port, this is pointing towards a new lr unit at the moment.

As per the RAVE extract.....

The Immobiliser system in the L322 only prevents cranking...if it cranks then the immobiliser system is correctly deactivated....

You could be looking at lack of fuel pressure...

Take the engine acoustic cover off and find the fuel rail schreider valve....crank the engine for say 6-7 seconds, enough to build fuel rail pressure.... then whip round to the engine and using a rag to catch any spray (and no smoking or sources of ignition!!) press the centre part of the schreider in (as if you were letting a tyre down)...you should get a good spurt of petrol...if not, your intank pump is US or the fuse/relay thereto is duff....

Read my woes... http://www.landyzone.co.uk/lz/f10/non-starter-oh-feck-200190.html
 
As per the RAVE extract.....

The Immobiliser system in the L322 only prevents cranking...if it cranks then the immobiliser system is correctly deactivated....

You could be looking at lack of fuel pressure...

Take the engine acoustic cover off and find the fuel rail schreider valve....crank the engine for say 6-7 seconds, enough to build fuel rail pressure.... then whip round to the engine and using a rag to catch any spray (and no smoking or sources of ignition!!) press the centre part of the schreider in (as if you were letting a tyre down)...you should get a good spurt of petrol...if not, your intank pump is US or the fuse/relay thereto is duff....

Read my woes... http://www.landyzone.co.uk/lz/f10/non-starter-oh-feck-200190.html



weird... when i was playing with my faultmate once i managed to un-sync the keys. keys would turn on ignition and allow cranking, but fuel supplies were disabled so stopping the engine from starting :confused:
 
weird... when i was playing with my faultmate once i managed to un-sync the keys. keys would turn on ignition and allow cranking, but fuel supplies were disabled so stopping the engine from starting :confused:

Really?? that is contradiction to the RAVE extract above...may the diesel immobiliser system is different - who knows....

hmmmm....maybe further research is required! I will see how the immob system on my 7'er works as it is basically the same system.
 
well with the replacement ecu i tried it in the car the day i bought it car cranked but would not fire same as it's doing now, but car runs fine with my faulty ecu, so it rules out the fuel pump etc as the car is now running on my original unit, but i have just picked up off rangerovers.net as well as cloning the ecu there is a eeprom that also needs to be cloned, this perhaps holds the coding preventing my car from firing
 
I am going to resurrect an old thread here as i have been looking into updating the engine ECU software as I had my 04 4.4 plugged into an autologic system the other day and it said i needed an update but I chickened out as it gave two options and we weren't 100% sure.

Has anyone ever updated the engine software that they know of, most likley during a main dealer service, i believe there is a transmission one as well.
Mine is still the original 2003 software on my 2004 4.4 v8.
the reason i ask is my car has had a drivetrain clunk since i have had it and on the 2006 vehicles, according to ZF, the clunk is cured by and engine ECU upgrade to stop the throttle snapping open or something.

Regarding the problem above, i had the same issue a few times after i disconnected the battery and i had to get the main dealer to connect up to T4 and re teach the link between the immobiliser and engine ECUs.
i am very lucky now to have a faultmate that can do it for me and the basic procedure is put the engine ECU into learn mode, then go to the immobiliser ECU and send the code, then put the engine back into normal mode and you are away.
Without that my car would crank forever but no fuel or ignition.
 
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