Technical Immobiliser wiring issue

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Technical Immobiliser wiring issue

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Jan 10, 2011
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So as title suggests, I have a grande punto .1.2 2007 . I'd like to add I've bought it yesterday as a none runner.
It is showing a immobiliser fault on the dash.
I've so far connected up Mes and checked the ecu for errors.
I can connect to all aspects of it including body computer, engine, etc

A few things I've found that are raising alarm bells.
There is a fault code in relation to the cooling fan and air con.. The car DOES NOT have Aircon...! Amongst other faults( see picture)
There is a fault with main beam, upon trying main beam only side lights stay illuminated, dip beam turns off. Horn, indicators steering controls etc all function normally.
Also a Minicrypt fault that does clear but returns at next start attempt.

I've checked the engine bay fuse box for corroded pins and found 2. One was on a relay for headlights R15, but when I sorted that connection with a new pin, the main beam problem persists.
The other was on the relay for Ignition main circuit R12.
I've checked pin 1 on ecu connector on the right, and pin 15. I've tested at fuse box, to loom that end and I've got continuity. I didn't however check for 12volts at the ecu end. I will try that tomorrow.
I've checked and cleaned and replaced the earth straps, used jump leads as additional grounding and no joy.
I've checked drivers door loom for broken wires and found no damage at all.
Now for the red flags

1. Air con showing on MES although its not an aircon model
2. The fuse box has writing on it, maybe replaced already?
3. Upon checking the internal fuse box, it wasnot bolted in and obviously had been removed at some point. ( maybe replaced?)...

I can get the car to momentarily crank if I cycle the key on and off quickly, it just spurs for a second but doesn't fire, so starter works.
Fuel pump primes, car locks and unlocks on remote for.
There are 2 keys, 1 Remote, 1 normal and about 4 other standard keys I guess for petrol cap. Neither of ignition keys start the car.

I'm certain I found all broken wires under fuse box in engine compartment but have read about a connection in bulk head.. but I think he was corrected to the right ecu connector.

Any advice as to my next thing to check appreciated.

I would buy a new ecu lockset as had a similar problem on a grande before and swapping out the set fixed it.. BUT if I buy the same set as on there now it may be wrong as its showing as an air con model( should that make any difference to starting?)
 

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So I've tested pin 1 and 16 for 12v and it's present at both.
The only real other explanation for no start is a dead ecu, but I can connect to it fine and
The car will crank for a split second if I cycle between off and start fast enough to beat the immobiliser.
So starter motor is good.

Any help appreciated
 
Is it the original ECU? As you said your car doesn't have air-con but your MES is reporting faults with air-con, which makes me wonder if someone swapped in a replacement ECU (that has air-con programmed to it on the previous car)

You would also get abnormal readings from MES if you are using the wrong cable, or if you select the wrong ECU model from the list, so worth double checking that
 
I'm well versed with the mes. And have vague kkl and elm cables , with the colour coded attachments.
Yes I'm confident it's already had a replacement ecu set as I stated in my first comment..
None the less, mes has highlighted a faulty ecu so I've ordered a new set, if it works happy days , if not ill part out the car.
 
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