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Discussion Starter #1 (Edited)
Hi Guys,

A little bit stuck here, so any help would be appreciated.

Quick Background:

2003; 147; TS; 2.0

Did an overhaul on the engine etc and put it all back together again. When i turned the ignition key on i saw the following on the dash.

1. Check engine light flickering
2. Selespeed Failure
3. VDU Failure
4. Immobilizer Failure

Used MultiECUScan to check. (Before the overhaul i could connect to both engine and gear but now i could only connect to the gearbox). I got the following codes.

format : Code from scanner : MultiECUScan Description : [OBD2 Description provided in sticky notes of this forum]

P1746 : Lever Switch 1 : [Pressure Control Solenoid "A" Open Circuit]
P1747 : Lever Switch 2: [Pressure Control Solenoid "A" Short Circuit]
P0715 : Turbine Speed Sensor 1: [Input/Turbine Speed Sensor Circuit Malfunction]
P1763 : CAN Messages Reception: [not available in list]
P1770 : Accelerator Pedal Signal: [Clutch Solenoid Circuit Malfunction]

I tried erasing the codes and was left with the last 2 (P1763,P1770). I tried some actuation tests and most of them worked fine. Later i walked out to the engine bay with the ignition still on and could hear a mild flickering from the throttle body. I pulled out the connector grip to the throttle motor and checked the dash again. The check engine light stopped flickering and was now solid amber. All the other failure messages disappeared as well. I tried connecting to the engine ECU and it worked. Having removed the grip from the throttle body, error codes are expected. I got a few and after erasing i was left with the following.

P0120 Throttle Potentiometer: [Throttle Position Sensor/Switch A Circuit Malfunction]
P1121 Throttle Potentiometer Track 1: [Throttle Position (TP) Sensor Circuit Intermittent High Voltage]
P1122 Throttle Potentiometer Track 1: [Throttle Position (TP) Sensor Circuit Intermittent Low Voltage]

I've been through many posts and have cleaned all the fuses in the engine bay and checked/cleaned all the earth points including the one on the throttle body. I used contact cleaner spray everywhere i could find an electrical grip including cleaning the battery terminals.

I plugged the grip back on the throttle body to check if there was any change but its back to the original problem with all the failures showing up on the dash and the flickering check engine light. Next i was thinking of continuity testing but needed a diagram to test things.

I was hoping someone would have a wiring diagram they could share or if anyone has managed to resolve a similar issue.

Found a youtube video showing what its currently doing.
 

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That’s a lot of random fault codes there, can’t help thinking it is wiring related. You have cleaned earths but have you checked them with a meter back to battery neg to make sure they are connected to earth?
 

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These phenomena sound like when the ECU from a GT/GTA 3.2 is defective. I suggest you start looking for a replacement... (sorry)
 

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Discussion Starter #4
Didn’t get notifications from this thread. Thanks for the reply guys.

@jhonny ; I will check that now. Thanks.
@Wally; yeah I’ve looked up the issue and in some cases it’s solved by cleaning the connections and other cases mention replacing the ECU. Thanks.
 

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Discussion Starter #5
All points are connected to earth. Any metal point on the engine/transmission/body is connected pretty well.
Looking for matching ECU now.
 

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You do realize that unless you are fitting a "Virginized" ECU you have to replace the whole set of Engine ECU, Body Computer & Immobilizer Chip with a matching set from the same donor car?
 

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Is it charging correctly? I'd have to wonder if the alternator regulator has a defective diode and is sticking some AC voltage into the electrics, driving the ECU a bit nuts.
 

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Discussion Starter #8
You do realize that unless you are fitting a "Virginized" ECU you have to replace the whole set of Engine ECU, Body Computer & Immobilizer Chip with a matching set from the same donor car?
Thanks for the info. I didn’t know that. I found a guy on gumtree day before yesterday selling exactly what you have specified. The numbers on the Ecu matched and he didn’t want to sell it separately so I purchased the whole set. Will install it today.
 

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Discussion Starter #9
Is it charging correctly? I'd have to wonder if the alternator regulator has a defective diode and is sticking some AC voltage into the electrics, driving the ECU a bit nuts.
The vehicle does not start. This happens when you turn the ignition on.
 

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Discussion Starter #10
You do realize that unless you are fitting a "Virginized" ECU you have to replace the whole set of Engine ECU, Body Computer & Immobilizer Chip with a matching set from the same donor car?
So after changing the body and engine Ecu the flickering is gone. I missed the Earth point on the throttle so was getting vdu/selespeed failure issues. I managed to clear all the codes on the engine and gearbox however when I plug in the throttle grip I can no longer connect to the engine ECU. But that’s ok for now as all the errors are gone.

Only problem that remains is immobiliser failure. I think that is stopping me from starting up. The engine seems to turn fine but gives no indication of firing up.

I engine light gives The following code:
U1600 - Electronic key

I have the card which has a manual and electronic code but not sure what to do with them. I cannot connect to the body computer with my obd cable. It’s a simple elm cable.

Any ideas?
 

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Remove the Immob Chip from the donor FOB and put in your key FOB. BUT BE VERY CAREFUL, as they are glass and easily break with age.

Hopefully your car will now start.
 

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Discussion Starter #17
Glad to be of service.

(Where do I send the bill) :grin:
lol... still not completely out of trouble though... engine is working well now and no problems on that side (not sure if i mentioned it has been overhauled and this was the first start). backstory here incase you're interested (https://www.alfaowner.com/Forum/alfa-147-156-andamp-gt/1124777-147-petrol-smoke-oil-in-exhaust.html)

I got Selespeed failure on the dash and cannot engage gears. the front of the vehicle is still on jack stands (not sure if that makes a difference). Hooked it up and found the following codes.

P0715 - Turbine Speed Sensor (1) [this one is a permanent error, in red, says no signal]
P1758 - Clutch Solenoid Valve Current [can be cleared]

I checked the sensor grip in the front (next to drain plug) and both seem to be on and locked-in firmly. I will try removing and cleaning the sensor then try again. Also cleaned the relay and plug next to the battery as well as the ABS control unit grip with electrical contact cleaner just incase it was an electrical issue but that didn't resolve anything. I found out the relay is for a pump.

anything else i could do to sort it out? continuity test from sensor to computer maybe? all the items in the fuse box next to the battery have been cleaned already.
 

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