Technical Wiring connection to coil packs ECU IAW4AFS2, 51793116

[Bamboo Panda]

Hello,

Does anyone have details for the wiring connections from the ECU to the coil packs and injectors on a 2007 (mk 3) Panda 1.2 Eleganza? (i.e. pinout)
The ECU numbers are IAW4AFS2, HW407/20BB-WHM, 51793116
Different versions on the mk3 Panda have different ECUs with different pinouts. This particular model has a 28 pin connector on the ECU (not the same as the model in the e-learning manual) The car has an ignition problem, I think the fault is in the wiring.. Obviously I have googled this to no avail.
Thank you in advance if you have the details or know where I can get them.

 

[koalar]

can't help with pinouts

however there are two wires direct no joins from the coil pack to the ecu (very easy to beep through) and two wires (will be the same colour) with permanent battery supply (shared with the injectors supply)

 

[Bamboo Panda]

can't help with pinouts

however there are two wires direct no joins from the coil pack to the ecu (very easy to beep through) and two wires (will be the same colour) with permanent battery supply (shared with the injectors supply)

Thank you for the reply. apparently FIAT used to publish the wiring info, but don't do so any more.

 

[MrMagoo]

What are the OBD codes?

 

[Bamboo Panda]

Thanks for replying. The code is P0352. Temporary fixes tried by a mechanics and an auto electrician have been to slightly bend one of the pins on the ECU to force contact and to strap the cable to the ecu to try to isolate the connection from engine vibrations. Both of those "fixes" worked fine for a week or two. The ECU has been tested (ECU technologies) - no faults. I've been quoted £1200 by FIAT. for the wiring loom (!).

 

[Bamboo Panda]

What are the OBD codes?

Thanks for replying. The code is P0352 (Ignition Coil B Primary/Secondary Circuit Malfunction)
Temporary fixes tried by a mechanic and an auto electrician have been to slightly bend one of the pins on the ECU to force contact and to strap the cable to the ecu to try to isolate the connection from engine vibrations. Both of those "fixes" worked fine for a week or two. The ECU has been tested (ECU technologies) - no faults. coil packs and spark plugs are new, spark plug cables are fine (replacement tried - no change). I've been quoted £1200 by FIAT. for the wiring loom (!).

 

[koalar]

electrician have been to slightly bend one of the pins on the ECU to force contact

so we already know the fault is between the ecu and plug.


some people have had success by cable tying the connector down firmly

 

[DaveMcT]

By the sounds of it, you need a new connector. Cut the connector (complete with useful wire lengths) from a scrap car and splice it to your loom. You will need solder, a wire holding tool and heat shrink sleeve.

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[MrMagoo]

I had wild goose chase on a similar fault with my sh!tty Peugeot. Took the loom apart and belling out wires etc., and it was a faulty spark plug in the end giving very random codes!
Please confirm you are seeing zero voltage at the coil pack in the fault condition.

 

[Bamboo Panda]

By the sounds of it, you need a new connector. Cut the connector (complete with useful wire lengths) from a scrap car and splice it to your loom. You will need solder, a wire holding tool and heat shrink sleeve.

https://www.ebay.co.uk/itm/38437181...zjENOPFiB30PBrmGl6epfCSdQA==|tkp:BFBM0vvIs79f

Thank you, I have had no luck sourcing a used replacement part, but I actually managed to find the ECU pinout on Haynes (Autofix) - the faulty connections are probably the ECU coil pack connectors which are the top right pin (pack 1) and the pin immediately to the left of top right (pack 2) that is for IAW 4AF or IAW 4AFS2 ECUs

 

[Bamboo Panda]

I had wild goose chase on a similar fault with my sh!tty Peugeot. Took the loom apart and belling out wires etc., and it was a faulty spark plug in the end giving very random codes!
Please confirm you are seeing zero voltage at the coil pack in the fault condition.

Thank you - I'm pretty sure it's the wiring loom - having finally found the pinout I hope to make progress!

 

[Bamboo Panda]

so we already know the fault is between the ecu and plug.


some people have had success by cable tying the connector down firmly

Thank you - I have tried that. As I have the pinout now - I hope to get it sorted.

 

[Bamboo Panda]

Thanks for replying. The code is P0352 (Ignition Coil B Primary/Secondary Circuit Malfunction)
Temporary fixes tried by a mechanic and an auto electrician have been to slightly bend one of the pins on the ECU to force contact and to strap the cable to the ecu to try to isolate the connection from engine vibrations. Both of those "fixes" worked fine for a week or two. The ECU has been tested (ECU technologies) - no faults. coil packs and spark plugs are new, spark plug cables are fine (replacement tried - no change). I've been quoted £1200 by FIAT. for the wiring loom (!).

I later was quoted £490 for the wiring loom by a different FIAT dealership.

 

[DaveMcT]

There are plenty of Pandas in scrap yards but parts like the engine wiring loom are almost never advertised. You will have to phone a few breakers until you find the parts you need.

 

[koalar]

P0352 could easily be the power to the coil, its not unknow for the connectors to be spread wide on coil connector, Power comes direct from a relay and fuse. Try gently wiggling the wires

are you sure the fix by bending the pin on the ECU plug wasn't just a coincidence ?

post some photos of the plugs, maybe something shows up

 

[koalar]

heres how I see it

The ECU isnt sensing any voltage from the coil and throws up a P0352 tell you the voltage is missing

the relay and fuse are probably fine, The also feed the injectors and the other coil, you should be other codes


I would start by measuring the voltage coming into the ECU plug if there's no voltage the fault is likely to be break in the wire to the coil , The coil connector, the coil (yes I know its new), or wire from the coil

if 14V is getting to the ECU plug and the ECU is fine then the plug has to be faulty

 

[Bamboo Panda]

heres how I see it

The ECU isnt sensing any voltage from the coil and throws up a P0352 tell you the voltage is missing

the relay and fuse are probably fine, The also feed the injectors and the other coil, you should be other codes


I would start by measuring the voltage coming into the ECU plug if there's no voltage the fault is likely to be break in the wire to the coil , The coil connector, the coil (yes I know its new), or wire from the coil

if 14V is getting to the ECU plug and the ECU is fine then the plug has to be faulty

View attachment 404375

Thank you for the reply. I n the end it seems I have managed to fix it (although I've only had a week's use with a couple of motorway trips so far).
The solution was just to very carefully nudge the ECU pin a hair's breadth to the left. Hayne's Autofix manual gave me the pinout. For the Magneti Marelli IAW4AF and the IAW4FS2 if you stand infront of the engine with the ECU in place, then the top right pin is coil pack A (or 1) and the pin immediately to its left is coil pack B (or 2) - the connection to coil pack B was the problem in my case.

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[Bamboo Panda]

Hello,

Does anyone have details for the wiring connections from the ECU to the coil packs and injectors on a 2007 (mk 3) Panda 1.2 Eleganza? (i.e. pinout)
The ECU numbers are IAW4AFS2, HW407/20BB-WHM, 51793116
Different versions on the mk3 Panda have different ECUs with different pinouts. This particular model has a 28 pin connector on the ECU (not the same as the model in the e-learning manual) The car has an ignition problem, I think the fault is in the wiring.. Obviously I have googled this to no avail.
Thank you in advance if you have the details or know where I can get them.

In the end I managed to get the pinouts from Haynes Autofix - a very very slight nudge left to the correct pin that connects to coil pack 2 seems to have done the trick - coil pack 1 connects to the top right (as you face it standing in front of the car) ECU pin and coil pack 2 connects to the pin to the left of that.