No ignition, new battery just fitted, no turn over. dash lights go out but no sound.

[Norm]

Pulled onto drive, all was well - next day turned the key nothing. As the care is 6 years old, I suspected the battery needed replacing. It registered just 10.5v. Put in the new one (correctly, checked 12.5v) - lights worked, radio came on, doors lock and close. Then turned to start - nothing!

It's a 2.0 diesel auto. Up to this point, it worked fine. Any suggestions would be most welcome ... HELP!

I could add that it is in "P" park. But it's as though it's not when I turn the key.
I checked as many related fuses for ignition - can't see any blown. But I'm wondering about the "P" position and if the computer is picking it up. Any suggestions?
Just in case people want to know more: the first battery gave odd security warnings when it would not turn the engine. On the day of replacement, the ignition lights would not come on at all, so this 15sec turn ignition turn off ignition then remove the neg terminal was not possible. So, as a last resort, before I call for a mechanic to come out, tomorrow morning I will go through this procedure again with the new battery. Any advice welcome! ('Good luck' would be nice.)

I will post again tomorrow.

[Norm]

Sorted. - A loose connection. Something simple and overlooked.

[sriray]

Glad you solved it

[Norm]

Sorted. - A loose connection. Something simple and overlooked.

Thanks!