Help! Car won't start :(

[mikemk4gti]

Ha ha, that's me that's breaking one on eBay, but not got an ecu.
Where are you?

[tomp]

Ha ha, that's me that's breaking one on eBay, but not got an ecu.
Where are you?

Oh right, no use there then!

[bodga]

Thought i recognised that golf in your sig mike. I'm the bloke who brought the bonnet of your dad the wk end.

[mikemk4gti]

It was running fine back then, only packed up today

[mk2bal]

Not witnessed it myself, but have heard of it a few times now. It seems having the gearbox earth removed causes starter return currents to flow through the ecu killing it. Always ensure all earths are in place before connecting battery/ new ecu. Also I think you want to connect earth before pos, as you ensure a return path which some components require

[mikemk4gti]

Ordered a replacement ecu now, hopefully it will be here tomorrow.
I've fitted a new earth from the battery to the gearbox. Is there anything else I should do or check to prevent it happening again?

[clipperjay]

Do you have a braided one from the ECU to the bonnet?
Plus we tend to double the negative lead to a gearbox bolt.

[tomp]

Not witnessed it myself, but have heard of it a few times now. It seems having the gearbox earth removed causes starter return currents to flow through the ecu killing it. Always ensure all earths are in place before connecting battery/ new ecu. Also I think you want to connect earth before pos, as you ensure a return path which some components require

I'm sure its positive first when reconnecting a battery, and positive last when disconnecting.... 

[mikemk4gti]

It's fixed, the replacement ecu turned up this morning.

[mikemk4gti]

Do you have a braided one from the ECU to the bonnet?
Plus we tend to double the negative lead to a gearbox bolt.

No there's no earth on the ecu at all? Should there be?
I added another to the coil as I had a spare from another mk2 I'm breaking.