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Discussion Starter · #1 ·
Hi, I wondered if any of you Alfa experts can help with this issue. I recently bought a 2008 1.6TS with a broken timing belt. After much consideration I decided the most cost effective fix was to buy a second hand complete engine. I fitted this and put a new timing belt on and the car was running fine. I drove 15 miles in it with no faults. It then stood for about a week and when I started it it came up with the engine light on, motor control failure and ASR system failure.

When I read the codes there were many- mass or volume air flow circuit, throttle pedal position sensor, camshaft position sensor, fan 2 control circuit, speed sensor A and P1221 manufacturer specific.

Needless to say the car is in limp mode. I figured this must be a wiring issue with so many faults all of a sudden. I disconnected the battery and removed the sockets attached to the ECU over the throttle housing. In the left hand plug I found a tiny piece of rusty metal. It was magnetised so stuck to the screwdriver. This was around the centre of the plug. Now I am wondering whether this foreign body has shorted the ECU and caused all these faults. There is no visible sign of any issue and all fuses seem to be OK. What is noticeable is the cooling fan runs as soon as the ignition is switched on from cold. I believe this means the ECU is not seeing the temperature sensor?


Can anyone enlighten me whether there is any short circuit protection in the ECU and if not whether the damage is likely to be in the ECU in the engine bay or the body ECU under the dash? The battery now drains very quickly and with everything off it draws over 1 amp. I haven't investigated exactly what is causing the current drain yet.

I can still connect to the ECU OK. It seems amazing that this metal object only caused a problem after the car had been standing, or is it possible that there is actually something else wrong and the metal piece actually has nothing to do with it?

Has anyone else seen a similar problem and if so how to go about diagnosing it. I don't have any circuit diagrams or ECU pin out charts. It would be most helpful if someone could tell me where I could locate those.

I do have a spare engine ECU that came from the donor engine but I believe that wont work as it needs to be coded to the ECU under the dash and the key transponder?

Any help with this would be greatly appreciated

Many thanks
 

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Low battery voltage, probably due to the current leak that you mention, might cause all sorts of random false errors. Check the battery voltage and if low recharge and see if errors are still there. If this clears the errors then try and find out what is causing the current leak.
 

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Check the battery condition and your earth connections, both can cause problems like this. Also, you could try removing a fuse at a time and watching the effect on the battery drain on a multimeter, this may help isolate the circuit that is causing the circuit drain...
 

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Discussion Starter · #5 ·
Check the battery condition and your earth connections, both can cause problems like this. Also, you could try removing a fuse at a time and watching the effect on the battery drain on a multimeter, this may help isolate the circuit that is causing the circuit drain...
Hi thanks all for your input. I have tracked the current drain to fuse F39. Connected to that is the climate control and radio and maybe a few other things.

I have found that when the meter is first connected the current is 0.3A and then it shoots up to 1.4 and I can hear a noise coming from inside the dash. Maybe something to do with climate control? There is another fuse which has 0.4A across it which I think is the central locking? This also seems far too high?
 

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Multiple errors + Battery Discharge = malfunctioning Body Computer

I had similar sudden multiple errors on my 147. Besides these errors I experienced occasional discharges of the battery. And the reason for these anomalies was malfunctioning body computer.
Malfunction body computer (BC), occurred because of a slight corrosion on the circuit board of BC, this was the result of imperceptible water in the cabin, on the tapestry around the fuse and BC's. At heavy rain fabric around fuses was quite moistly. There were small leaks of water in the car- under windshield wiper cover (which is recognised as common mistake). The water came in the interior from the area under windshield, by the wire, which is used for opening bonnet.
To clear the mess of all errors and battery discharges I need to replace BC and fill plaster in cracks at the joints in the area where are located the wiper motor (that were made carelessly). The additional sealing rubber bands are needed around the outer casing where boot wire passes from engine compartment into the cockpit.
The body computer is allocated under the dash, behind fuse box and obd2 connector. When replacing BC's particular caution is needed, as these vary depending on the power (optional) equipment of the vehicle.
 

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Discussion Starter · #7 ·
I had similar sudden multiple errors on my 147. Besides these errors I experienced occasional discharges of the battery. And the reason for these anomalies was malfunctioning body computer.
Malfunction body computer (BC), occurred because of a slight corrosion on the circuit board of BC, this was the result of imperceptible water in the cabin, on the tapestry around the fuse and BC's. At heavy rain fabric around fuses was quite moistly. There were small leaks of water in the car- under windshield wiper cover (which is recognised as common mistake). The water came in the interior from the area under windshield, by the wire, which is used for opening bonnet.
To clear the mess of all errors and battery discharges I need to replace BC and fill plaster in cracks at the joints in the area where are located the wiper motor (that were made carelessly). The additional sealing rubber bands are needed around the outer casing where boot wire passes from engine compartment into the cockpit.
The body computer is allocated under the dash, behind fuse box and obd2 connector. When replacing BC's particular caution is needed, as these vary depending on the power (optional) equipment of the vehicle.
i, as I said I found a fragment of metal in the connector on the engine ECU. This could possibly have caused a short similar to the symptom you talk about. There are certainly no water leaks into the cabin. If I disconnect the body ECU the current drain goes down to nearly zero, but that does not prove it is the ECU. I have some more things to try before I finally diagnose the ECU as the failure. The current drain is constant on mine but there is no visible damage to the ECU. The car no longer runs even with charged battery.
 

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Discussion Starter · #8 ·
i, as I said I found a fragment of metal in the connector on the engine ECU. This could possibly have caused a short similar to the symptom you talk about. There are certainly no water leaks into the cabin. If I disconnect the body ECU the current drain goes down to nearly zero, but that does not prove it is the ECU. I have some more things to try before I finally diagnose the ECU as the failure. The current drain is constant on mine but there is no visible damage to the ECU. The car no longer runs even with charged battery.
I have now concluded that the ECU is the problem. I traced the current draw to the drivers door. When shut it it draws 0.04A and when open it draws 1.4A. But this is not consistent as the battery went flat in a few days with the door shut. Also if I disconnect the drivers door cable the current draw goes away but the engine fires but will not run. There is no visible damage to the ECU. Now I am trying to find a second hand ECU set. Does anyone know if the part numbers need to be the same as I have found a set off a 2004 1.6TS but the part numbers are different. I have posted the numbers in a different thread related to ECU swap.
 

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Discussion Starter · #9 ·
I have now replaced the ECU with a second hand unit and I can confirm that the car now runs with no errors reported.
 
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