New engine, immobiliser fault...I think

[adamthegianthippo]

Hi,

I have just replaced my clio 172 engine as the cam belt died on it.

Trying to start it now and it wont crank, I think it is an immobiliser problem but there is conflicting information on the forum.

When I try to turn over the car the red light in the middle of the dash stays lit... I think it should go out?

Thanks

Adam

 

[Adam-o]

yeah sounds like the immo, try checking all the earth cables to start with, i think theres two. in the passanger wheel arch and one going to the gearbox.

 

[adamthegianthippo]

Ive checked the earth cables; the one on the gearbox and the starter motor.

Any other ideas.....

Thanks
Adam

 

[Andrew Cooke]

it should still crank, does the pump prime?

 

[adamthegianthippo]

Yes the pump primes.

 

[Andrew Cooke]

ok, so the ECU has power. That's a start.

Do you have a volt meter or something? Check for 12V from the big fat cable at the starter to the engine, or if that's too hard from the big fat cable on the alternator to the engine.

If that's ok, you need to check for 12V at the small wire on the starter when you turn the key to the cranking position.

 

[adamthegianthippo]

The red cable on the alternator had roughly 12v and the starter motor did aswell.

 

[Andrew Cooke]

if you undid the connectors in the fuse box I'd be giving them a clean / wriggle.

 

[adamthegianthippo]

I tried to start it again, and it tried to start but then stopped.

 

[adamthegianthippo]

To add to the confusion the engine now turns over for 5 seconds only if I start the engine immediately after getting in the car. After this everything goes dead, all the electrics die, I have to disconnect the battery to get any electrics back.

Any other ideas?....

thanks

 

[Adam-o]

it's the immobiliser thats causing this to happen, while changeing the engine have you changed the ecu?

 

[adamthegianthippo]

No I haven't changed the ECU, i was under the impression it doesn't need to be changed?

Thanks

 

[Adam-o]

no, you don't have to change it, i'm just trying to think what might be causing it. Have you checked all the fuses? does your key work fine? i mean in case the battery died?

 

[Muppeti]

Try leaving the key in the on position for a while. Had to do this on mine when the battery went flat.

 

[adamthegianthippo]

I have checked the key battery, that is fine. I have checked the fuses and they seem OK. I have left the key in first stage for 5mins then locked and unlocked the car, and that didn't work. The battery is fully charged as I checked that.

I think the immobiliser got upset with me as I left the battery off for 4 weeks.

 

[Muppeti]

Its strange i had my batter off my car for a week and i had the turning over for 5 seconds then cutting out problem. I just left the key in for a while came back and it turned over, very weird.

 

[Adam-o]

well I had the same problem but it came down to bad earth cable, not sure what else might be causing it

 

[adamthegianthippo]

I think im going to ask on the forums for some help, as its probably easier to diagnose when your next to the engine...if anyone lives near me.

Thanks again for all the help and ideas, its much appreciated!

 

[charlie_racer]

My track car is doing the same thing going to try new ecu uch key set I've got and see what happens I'll let you know