Clicks and flashing lights when attempting first start
 

Good Evening,
I am at the point of the first start after head off round 2 of Timeserts to Bigserts. It's been a couple months since I had the car started. I put a charger on and when I went to crank it over, all I got was some loudish clicks and headlight flashes. Is this an anti-theft reaction? I disconnected the battery and put the charger on the battery without any terminals attached. Suggestions?
I thought I had all the electrical connections properly reconnected. I didn't disconnect any starter wires or alternator wires. I did disconnect the big hot wire at the + box to get the intake off. I have a couple DME codes and a vanos code that should go away once I build oil pressure.

That's just the typical sounds of a battery with not even nearly enough power to start engine.
Trickle charger it for at least 1 day. Don't get impatient and try before that. So NOT let your X5s alternator do the heavy lifting or you will be buying another alternator soon.

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Sounds like the battery doesnt have enough amps to start the engine. If after chargering the battery for a day and it still doesnt start,could possibly be a bad battery. May need to do a load test on the battery.

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It was the battery.
I charged it over night and took it to NAPA to be tested.
It was a 900 CCA really good battery. It was dead.
They replaced it under prorated warranty for $52.00
put it in and the motor fired right up.
Now I have to chase 2 codes, 44 DME Activation solenoid valve tank ventilation and 3E Activation solenoid valve secondary air.
Thanks for the input.

Glad it's running. You might want to start a new thread on the code issues.

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