Technical Fiat Ducato 2016 key barrell coil / aerial.

[NZGrahamO]

Hi All

I have the padlock led up on the dash display.
No start etc.
Have had problem on / off.
This time fault will not turn off.
I believe that my model of Ducato 2016 the key barrel coil / aerial wiring goes direct into the body computer.
Older models had a code control interface box.
Have checked wiring between key barrel coil / aerial plug and the plug pins 7 and 8 on plug AV on the body computer.
The AV plug was removed from the body computer to test.
One of the AV plug pins number 7 has 11.5 volts on it tested to ground.
I would of thought there should be no voltage as both ends disconnected unless in the wiring bundle there is another supply tapped in.
Also does anybody know what the resistance ( OHMS ) of the key barrel coil / aerial should be.
I test at 245 ohms which does not seem right.
Also what voltage is used to power the key barrel coil / aerial.
With this info I will have a good base line to fault find the problem.

Thank You
Graham O

 

[Googlebot]

Hi All

I have the padlock led up on the dash display.
No start etc.
Have had problem on / off.
This time fault will not turn off.
I believe that my model of Ducato 2016 the key barrel coil / aerial wiring goes direct into the body computer.
Older models had a code control interface box.
Have checked wiring between key barrel coil / aerial plug and the plug pins 7 and 8 on plug AV on the body computer.
The AV plug was removed from the body computer to test.
One of the AV plug pins number 7 has 11.5 volts on it tested to ground.
I would of thought there should be no voltage as both ends disconnected unless in the wiring bundle there is another supply tapped in.
Also does anybody know what the resistance ( OHMS ) of the key barrel coil / aerial should be.
I test at 245 ohms which does not seem right.
Also what voltage is used to power the key barrel coil / aerial.
With this info I will have a good base line to fault find the problem.

Thank You
Graham O

Hi Graham,

I was under the impression it went directly to the BCM as well. No idea of the resistance or voltage I am afraid, for the price though, you may as well change it.

I changed mine last year, think it was less than £20 from Coastal Motorhomes for a genuine Fiat one. EBay have one here.

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I had worsening intermittent starts with the padlock symbol as well. Completely cured it and hasn’t done it since.

 

[Communicator]

I cannot remember the thread, but there was a recent post quoting 30 Ohms for the resistance of the aerial coil.

 

[jackwhoo]

+1 to thinking resistance of ariel ring looking high

 

[Communicator]

Hi Graham,

I was under the impression it went directly to the BCM as well. No idea of the resistance or voltage I am afraid, for the price though, you may as well change it.

I changed mine last year, think it was less than £20 from Coastal Motorhomes for a genuine Fiat one. EBay have one here.

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Find many great new & used options and get the best deals for Flexible Heat Exchanger Hose OE 51784914 Original Fiat Croma 1.9 at the best online prices at eBay! Free delivery for many products!

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I had worsening intermittent starts with the padlock symbol as well. Completely cured it and hasn’t done it since.

I have the earlier arrangement on my x244, with discrete code receiver. After a fail to start, and several failures of the padlock light to extinguish when tested, I cleaned tthe contacts at the code receiver. No problems since.
I am thinking that replacing the aerial ring would have had the same effect, but at greater expense.

 

[NZGrahamO]

I have the earlier arrangement on my x244, with discrete code receiver. After a fail to start, and several failures of the padlock light to extinguish when tested, I cleaned tthe contacts at the code receiver. No problems since.
I am thinking that replacing the aerial ring would have had the same effect, but at greater expense.

Hi

Thanks for your reply.
On the Fiat Ducato x290 the aerial coil ring wiring goes direct to the BCM.
There is no interface box as used on the Fiat x244.
I have found the problem that was causing the padlock dash light coming up and no start of motor.
I tracked the problem down to an intermittent loss of Can C high comms.
The fault was caused by pin 38 on the BCM ( M001 ) losing contact with the outgoing wiring ( Can C high ) in the D plug. ( 60 pin )
This stopped the can C high signal that handshakes from the BCM ( M001 ) to the ECM ( M010 ) to say key o/k / start motor / extinguish padlock light on dash.
This problem also brought up other faults on gearbox / ABS etc as they are all on the same Canbus C.
By re tensioning the female socket pin on the D plug it fixed the problem.
Now have a tight connection and all works well.
This shows that problems that show faults may not be faults at all but intermittent loss of Can C comms.

Thank You
Graham O
NZ

 

[Communicator]

Hi

Thanks for your reply.
On the Fiat Ducato x290 the aerial coil ring wiring goes direct to the BCM.
There is no interface box as used on the Fiat x244.
I have found the problem that was causing the padlock dash light coming up and no start of motor.
I tracked the problem down to an intermittent loss of Can C high comms.
The fault was caused by pin 38 on the BCM ( M001 ) losing contact with the outgoing wiring ( Can C high ) in the D plug. ( 60 pin )
This stopped the can C high signal that handshakes from the BCM ( M001 ) to the ECM ( M010 ) to say key o/k / start motor / extinguish padlock light on dash.
This problem also brought up other faults on gearbox / ABS etc as they are all on the same Canbus C.
By re tensioning the female socket pin on the D plug it fixed the problem.
Now have a tight connection and all works well.
This shows that problems that show faults may not be faults at all but intermittent loss of Can C comms.

Thank You
Graham O
NZ

Thanks for the informative and interesting reply. Luckily my x244 is canbus free.

 

[AnthonyH]

Hi All

I have the padlock led up on the dash display.
No start etc.
Have had problem on / off.
This time fault will not turn off.
I believe that my model of Ducato 2016 the key barrel coil / aerial wiring goes direct into the body computer.
Older models had a code control interface box.
Have checked wiring between key barrel coil / aerial plug and the plug pins 7 and 8 on plug AV on the body computer.
The AV plug was removed from the body computer to test.
One of the AV plug pins number 7 has 11.5 volts on it tested to ground.
I would of thought there should be no voltage as both ends disconnected unless in the wiring bundle there is another supply tapped in.
Also does anybody know what the resistance ( OHMS ) of the key barrel coil / aerial should be.
I test at 245 ohms which does not seem right.
Also what voltage is used to power the key barrel coil / aerial.
With this info I will have a good base line to fault find the problem.

Thank You
Graham O

How many keys do you have? If its just the one, then mostly likely you need a new key.

 

[Communicator]

How many keys do you have? If its just the one, then mostly likely you need a new key.

@AnthonyH See resolution in post #6.