Fiat 500 1.4 2007 on...

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TwoWaves
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Re: Fiat 500 1.4 2007 on...

Post by Technician » Sat Jul 01, 2017 11:20 am

I'm also lead to believe that it could have a software conflict!

Dcunning35
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Re: Fiat 500 1.4 2007 on...

Post by Dcunning35 » Sat Jul 01, 2017 1:57 pm

Prove out the inputs first , a software or pcm hardware concern would be were I would look only when I had confirmed the ect using a resistor and using live data for reference if the fans still dont actuate but do if the offending pins for pulling in relays at pcm are grounded it only leaves the pcm or software . Ok then use pass thru to check pcm calibration level .
Prove the ect then speculate.
Even the so called

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Re: Fiat 500 1.4 2007 on...

Post by STC » Sat Jul 01, 2017 11:17 pm

I'm also lead to believe that it could have a software conflict!
For a cooling fan on a 10 year old car !!! ???

What is your data source for this ?

I can see the benefit of an update, I wouldn't be applying it to the car though !

Is this another hypothetical example ?

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TwoWaves
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Re: Fiat 500 1.4 2007 on...

Post by Technician » Mon Jul 03, 2017 10:05 am

STC wrote:
I'm also lead to believe that it could have a software conflict!
For a cooling fan on a 10 year old car !!! ???

What is your data source for this ?

I can see the benefit of an update, I wouldn't be applying it to the car though !

Is this another hypothetical example ?
Back in the 1980's when I completed a course on electronics and microprocessors, we completed mapping, we did a module or two regarding software, and yes we also covered CAN and the nodes, the gateways, the data signals sent and received along with sensor and actuator fundamentals etc. yes I would believe a car as young as 10 years could have a software program in it that might be corrupt!

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Re: Fiat 500 1.4 2007 on...

Post by STC » Mon Jul 03, 2017 5:05 pm

We digress /waffle !

What do you see when back probed at the 2 ECU pins that pull the relays in as you activate stage 1 and 2 Cooling fan ?
Measured with a scope from ignition off > ignition on > fan 1 activated >fan 2 activated looking for any activity even if it is mVolts ??

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Re: Fiat 500 1.4 2007 on...

Post by Dcunning35 » Mon Jul 03, 2017 5:59 pm

Any master tech worth his salt will tell you to prove the inputs here first certainly before updating anything . The ect input will be the pcms focus for triggering the relays so just input a false reading to the ecm via a resistor as monitor the pcm output to relay thus proving everything back from the ect!!.
Think simple over thinking will just add confusion to the mix .
Danny

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Re: Fiat 500 1.4 2007 on...

Post by Dcunning35 » Mon Jul 03, 2017 6:01 pm

Out of interest does an open circuit on the ect not pull.in the fans permanently ,overheat protection?
Danny

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Re: Fiat 500 1.4 2007 on...

Post by victor2k » Mon Jul 03, 2017 8:41 pm

Try to perform first the active tests on cooling system,check the wiring betwwen ECU and the fan relays.
An older version of software will block the cooling of engine?A corrupted software of ECU will leave to update your software or will give you a useless piece of hardware and a lot of headache to replace a bricked ECU?
Best regards

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Re: Fiat 500 1.4 2007 on...

Post by Dcunning35 » Wed Jul 05, 2017 6:16 pm

How you getting on with this tech ? Have you had chance to prove out the input yet?.
Danny

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Re: Fiat 500 1.4 2007 on...

Post by STC » Sat Jul 08, 2017 12:08 am

Danny

I had a Fiat 500 in today with a similar fan fault. I got it Remapped and returned it to my customer. So far so good.

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