320d e90 not starting after flat battery

My e90 auto won't start after battery died and I tried to jump it ...scanner shows most codes related to dme not sending messages to transmission,fuel pump ,cluster etc etc ...checked all fuses ,relays then dme fuses and relays ...does anyone know how to check dme is getting power ? I have multi meter and fuse tester ...ECU doesn't look wet or coroded as common problem...any help appreciated,cheers

 

Your key may be out of sync with the imobilizer if so will need reset on a computer

 

Thanks for replying...I should have said that it turns over and fuel pump primes but won't fire up ... would the imobilser allow starter to engage?

 

Im not sure about that model but some will just wont fire

 

I think it shows wrong key or something on the dash if the sync is lost.

 

I have a few warnings on dash but not the key ...main one is red transmission cog ...maybe that is stopping it from starting?

 

Do you have a good, charged, battery in it now. Low voltage will cause errors in just about every module.

Charge the battery, clear all the codes and see what comes back.

 

in my experience, if battery is slightly suspect/old, replacement normally sorts it. You wouldn't (or would) believe the amount of errors a slighly low battery throws up.