Technical Immobiliser problem

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Technical Immobiliser problem

Thanks again loads of help with bits of knowledge gradually putting a picture together

NEED some dry weather now to get out under the bonnet
 
I have a x244 2006.

I only read about the immobilzer.
Can be a problem if the battery goes flat.

Then there is an emergency restart feature ?
The key is paired to the immobilizer. Needs to be programmed at a dealer.

Your battery in your key isn't flat? :idea:
 
Hi guys thanks for your on going support,

Communicator, lh or rh cab fuse box does not have a f37, there is f36 which is fine?

My dash led padlock symbol does stay on with ign on and f18 pulled, which confuses me as you say this indicates a loss of supply to CCU? F18 is the supply red and yellow

Read the thread you suggested and given the harness a good tug about and haven't been able to make it fail today!! Switched ign on and off twenty times! Bloody irritating thing!

Cheers Brian
 
Corcai, ive sent email to place you suggested tried to explain situation?

Don't know if they do a drive in service?

Thanks for your help
Brian
 
Brian,

Sorry that you are still frustrated.

I confirm that eLearn diagram E7010 for the key code system, shows the LED in the instrument panel as being supplied via fuse F37, which is sixth from LHS on the bottom row of the LH cab fusebox. I also have my own home brewed computer diagram, which shows F37 as a red 10A fuse in that location and that it supplies the instrument panel LEDs.

My thinkng was that if the code receiver (not theECU) was losing supply due to a wiring fault between it and F18, the LED would illuminate, which it should as the code receiver would not be working. You seem to have confirmed this.


When the problem occurs, do we know whether this is because there is no supply to the code receiver due to a wiring fault, or because the code receiver is not recognising the key? My suggestion of a temporary LED indicator to monitor the code receiver supply at the code receiver, was a possible way to resolve this. I fully appreciate that making the necessary connection close to the code receiver, is not the simplest of tasks. To elaborare, if the suggested LED is connected, and it remains illuminated when the fault occurs, then a supply failure to the code receiver from F18 is eliminated. That leaves a wiring problem to the ECU from the code receiver output, and a faulty code receiver as possible causes.
 
Hi, frustration for over 12 months now! With your help I am the closest I've ever been to understanding how the system works, but I'm not an electrician!

Basically you are saying to put a visual guide in to monitor the 12 volt supply? This would be the red and yellow cable in the multi plug at the CCU. Is this correct so far?

One other thing I don't understand is when the fault occurs, why does disconnection and reconnection of the multi plug at the CCU fix it? Effectively just cycling the power
 
Your chasing rainbows your code 2 box needs replacing if your fiat dealer can’t do it find some specialist that can program new code 2 box onto your chassis and ecu , I don’t always talk crap!
 
Hi Com, yes you are correct about fuse 37, I had no way of telling which one no markings on my fuse box lid just symbols, it is good and does stop the dash leds except the water in diesel one?

Now got a simple meter for checking 12 volt and continuity, so supply red and yellow to CCU IS live all the time with ignition off, assume this is correct?

Still waiting for a response from the autotronics place I messaged them direct from their website 4 days ago, so if they can't be bothered to even reply I'm not confident to use them shouldn't have to chase people
 
Communicator and Corcai, sorrow no contact for awhile, I go out to it most days and not had the bl.......y fault come up for couple of weeks! So not been able to check supply at pin 3, although this is live even with ignition off
Can you explain why when fault comes up simply disconnecting the multi plug at the CCU and putting it back fixes it?
Tried 3 key coding people now no one interested because it's so random?

Thanks Brian
 
Hi guys just been to asda for a shop van started ok home and shop, when back on drive switched off ok ign back on and padlock light on, so with meter on red and yellow and earth there is power on the CCU, also checked red and yellow to the black still have power which proves the live and earth paths to and from CCU Are ok?

What next?
 
Oh yes and 10 minutes later I tried it again and it had righted itself with me doing nothing?
 
No not yet, can't get anyone to show interest in trying to recode keys, as soon as I say it's intermittent they won't commit to even trying
Got one chap half interested but not really a key coder more of diagnostic normal faults
 
Hi again, could someone explain to me please if I have a key not recognised or wiring fault or CCU scrambled fault or com's fault to ecu, why does pulling the multi plug on the ccu and replacing it clear the fault? I'm at a loss to understand this and still can't get anyone willing to look at itL
 
No one can tell you for sure remotely. If it was me I would clone the eeprom into a secondhand unit. It's the only way to eliminate the code unit.
 
Thank you corcai for still showing an interest, I don't understand what an eeprom is our where it lives,

Do you mean copy the "eeprom' from my Code unit into another code unit and then try it on van?

Can this be done with a standard laptop and how would it be done or do you need special software to do this
Thanks Brian
 
Hi again, could someone explain to me please if I have a key not recognised or wiring fault or CCU scrambled fault or com's fault to ecu, why does pulling the multi plug on the ccu and replacing it clear the fault? I'm at a loss to understand this and still can't get anyone willing to look at itL

Hi Brian,

You have not been forgotten. I would venture to suggest the folowing possibilities:

1. In removing and replacing the connector, you are disturbing a wiring fault in the vicinity of the ECU, but do remember that the engine bay fusebox is close by. (It was a similar possibility that made me suggest a monitoring light for your code receiver supply. It is possible that by applying test prods, you could disturb a fault.)

2. There is a a fault in the ECU, which causes it to crash, and by unplugging, you cause the ECU to reboot.
3. Something else.

In reply to your later post:


EEPROM = Electrically Erasable Read Only Memory. Used to store relatively small amounts of data. I would expect an EEPROM to be used to store your key codes in the code receiver, fault codes and perhaps engine operating parameters in the ECU. Also the operating programs for the code receiver, and the ECU are probably stored in EEPROMs.
 
Communicator thanks for explaining eeprom, you mention fault with ECU, it getting reboted, do you mean ecu or CCU?
So does pulling the multi plug on the ccu cause the ECU to reboot, there is no noticeable delay in restarting after this?
When I tested for 12volt and earth i did so at the multiplug on ccu, my probes go in backof plug alongside the wires so nothing disturbed or disconnected when tested
I am driving around with the steering column covers off so have quick access in the event of a failure
Thanks Brian
 
Hi corcai, communicator, couple of questions from the guy trying to help me
1, the supply to the code unit on mine is permanent, should it be ignition switched?
2, can you post any wiring diagrams for connection to the obd socket

Thanks Brian
 
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