Opened up my ECU (Punto mk2 2001) Now it does not start :-()

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Opened up my ECU (Punto mk2 2001) Now it does not start :-()

puntoFix

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Hi

My friend the MEchanic?

Said I had a bad connection so I opened up the ECU but there was no way to get at the pins so I just arrodite the case closed again now it wont turn over!

Anyone know why it is the original ecu I did not change it and I removed battery before I removed it.
 
An ECU is essentially an embedded computer, so all the precautions you should take against electrostatic discharge when working on sensitive electronic components apply here too.

That said, modern electronics are pretty robust, unless you were wearing your best nylon shell-suit and had just shuffeled your loafers across a polyester carpet*, you're unlikely to have fried it.

More likely you've forgotten to reconnect something.

What happens when you turn the key?

Which lights come up on the dash? Which ones stay lit after a few seconds?

What sounds do you hear? (fuel pump, relays clicking)


What was the original problem?



*the carpeting in our college electronics lab was very inapropriate, by holding one pole of a capacitor and shuffeling, you could give someone quite a shock!
 
I was trying to fix fan not working on radiator, which comes on when I turn off the car and the temp sensor is bridged.

I was pretty carefully when opening it. I didn't do anything as I had some gel over the board so I just glued the case back together.

I hear the usually pumps whining on when I turn it on, as for the lights I don't think there are any on but I will double check later.

I read that if the ecu is not paired it won't turn over which is odd as its the original unit.
 
Lights when I turn key but not ignition in picture.

When I turn the whole way it just sounds like a dead battery. No lights are on at that point.

If I then turn off and then on without ignition get a flicking of lights coming on and off including code light which then turns off.
 

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Check all the battery and earth cables, pay sepcial attention to anything you moved when removing the ECU, guessing ECU is on side of batery box same as Panda.

Check/swap/charge the battery.


It's a power problem, not an ecu fault.
 
Battery is fine, the weirdest thing happens after I turn key i get all the pumps sounds but no lights then the lights up and then go off then come back up.

If I turn on the heater fan the dash lights go out the fuel gauge drops to zero.

when Iturn off the heater fan the lights come back and fuel goes up again. electric windows do the same thing but dont have enough power to move them.

Sounds like a short somewhere but I dont have a clue where to start looking?
 
Not a short, but a lack of current.

Check the earth (black) cable(s) on battery and where they connect to the car.

Could be live, but more likely earth.

To get the ECU out, you'd have moved these around, if thet're old and a bit corroded they could have broken at one end.


If the car was working before, it will be something you touched, or connected to something you touched, so start there.

Try connecting a jump lead from battery negative(black) to the engine, see if that makes a difference, then try it to something bare metal on the chassis, like a big bolt.
 
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