Technical Please help!! Trouble with new car!!

[LauraC8]

Hi guys
Okay so I bought a 2006 fiat Punto 1.9 mjet 2 days ago and this is how my problems have gone. I will to give as much information as possible but I'm not a mechanic.

Took the vehicle for a test deive, everything perfect, drove it home everything absolutely fine.

Next day want to go shopping, go to the car, it won't start. I think without looking its a dead battery so I wait for partner to come home so he can give me a jump start. Connect it all up and nothing. Hmmm do a bit more digging and realise the immobiliser light is on the dash (I don't know if it did actually have a flat battery)

Call the AA out as it's free so why not! He basically reset the ECU by unplugging and reconmecting, checked all the earth's which he said we're good and got the vehicle started after some more fiddling which I didn't really see. He had the car running but there was now someessages on the dash and the code reader. I had power steeeing light on and engine management and the yellow triangle with code U1706 on the reader which is unknown. He took the key out and the car engine stayed running!?! And he left me with a car you could just about start but the only way to stop it is to stall it!!

Tired so decide to do more investigation the next day (today) go to the car and completely dead!! Couldn't even unlock it with the button
Current have the battery on charge.

My two suggestions that have been made are either the ECU or the whole fuse box

Any thoughts much appreciated!

 

[g8rpi]

Hi guys
Okay so I bought a 2006 fiat Punto 1.9 mjet 2 days ago and this is how my problems have gone. I will to give as much information as possible but I'm not a mechanic.

Took the vehicle for a test deive, everything perfect, drove it home everything absolutely fine.

Next day want to go shopping, go to the car, it won't start. I think without looking its a dead battery so I wait for partner to come home so he can give me a jump start. Connect it all up and nothing. Hmmm do a bit more digging and realise the immobiliser light is on the dash (I don't know if it did actually have a flat battery)

Call the AA out as it's free so why not! He basically reset the ECU by unplugging and reconmecting, checked all the earth's which he said we're good and got the vehicle started after some more fiddling which I didn't really see. He had the car running but there was now someessages on the dash and the code reader. I had power steeeing light on and engine management and the yellow triangle with code U1706 on the reader which is unknown. He took the key out and the car engine stayed running!?! And he left me with a car you could just about start but the only way to stop it is to stall it!!

Tired so decide to do more investigation the next day (today) go to the car and completely dead!! Couldn't even unlock it with the button
Current have the battery on charge.

My two suggestions that have been made are either the ECU or the whole fuse box

Any thoughts much appreciated!

Did you buy privately or from a trader (even one with just a couple of cars for sale)? If it was a trader tell them to give you your money back and come pick up the car. If it was a private sale and you are not able to do the work on the car yourself it could be difficult. Rather than guessing remotely and you changing things it may be more effective to pay a competent auto electrician to look at the car. Where are you located? someone may be able to suggest a suitable electrician or garage. It could be a simple bad connection but it could get expensive.

Robert G8RPI.

 

[LauraC8]

Thanks for the reply!
I bought the car privately unfortunately!!
My partner does a bit of work on his own car so he can do small stuff, in no urgent need for the vehicle so to keep costs down we want to look into it ourselves
Any tips of what's most likely and where to look first?

 

[jackwhoo]

When connecting / disconnecting / connecting jump leads to the battery, make sure the keys are not in the ignition . Failure to do this can cause ecu failure , immobiliser problems and other issues.

 

[LauraC8]

When connecting / disconnecting / connecting jump leads to the battery, make sure the keys are not in the ignition . Failure to do this can cause ecu failure , immobiliser problems and other issues.

To be honest I can't recall if the light was on before trying to jump start (ie it never had a flat battery) and if the keys were in the ignition.

If this is the case is there anything to reverse the effect?

 

[LauraC8]

Oh if it makes any difference the night before all the problems started we had a lot of rain
I've heard water ingress can be a problem on these cars? But don't know if it could cause all of this

 

[jackwhoo]

To be honest I can't recall if the light was on before trying to jump start (ie it never had a flat battery) and if the keys were in the ignition.

If this is the case is there anything to reverse the effect?

Just bear in mind what I wrote if you are doing anything with the battery in the future.

 

[LauraC8]

Okay so done a little more digging today
Replaced the battery as it wasn't holding charge
Same issues try to start the car it won't because of the immobiliser light, reset the ECU and it'll start but won't shut down when the key is removed
On closer inspection, something is still running off the battery when no key in the ignition
This with the continuous running I narrowed it down to fuel solenoid or ecu fiddled around with fuses and it's the ECU is continuosly running causing the battery to drain and probably the engine to continue running.
Do I need to replace the ECU or is there something that can be done to it?

 

[Ralf S.]

I don't know if the ECU is supposed to realize by itself that the ignition is off and so turn itself and/or the fuel solenoid off too... but it's easier to make electrical components that just stop when the power to them is removed, so I'd say that they continue running because they are still getting a power feed from somewhere.

If they keep going, then that's great on the one hand (proves they work ) but the question would be, what's not working so that they keep going?

I dunno if the Body Control Module (under the dash, behind the fusebox) plays any part. There could be a relay on there that's supposed to "turn off" with the ignition... but which is sticking on.


Ralf S.

 

[varesecrazy]

Okay so done a little more digging today
Replaced the battery as it wasn't holding charge
Same issues try to start the car it won't because of the immobiliser light, reset the ECU and it'll start but won't shut down when the key is removed
On closer inspection, something is still running off the battery when no key in the ignition
This with the continuous running I narrowed it down to fuel solenoid or ecu fiddled around with fuses and it's the ECU is continuosly running causing the battery to drain and probably the engine to continue running.
Do I need to replace the ECU or is there something that can be done to it?

Hi . At top of Grande Punto section there is a list of FAQs..

Have a read.. plenty of info in there anout
Water damage and poor earths.

Charlie . Oxford . Cardiff

 

[digger58]

Stick my neck out a bit here, First thing I'd do is check all earth points and also check the fuse box for water ingress.