Volvo: resetting engine immobilsor on 850, dash light, noise test

Question
I have changed the battery on my 850 and it  will not start. No power is getting to the starter motor. The red LED light on the dash is constantly flashing. Had to re-code the radio. When the key is turned to start all that happens is that the dash lights dull and starter motor wise all is dead. Can you please advise solution to problem.                  Thanks very much.Ian

Answer
Ian,
You are not clear on what the starter is doing. "Dash light dim and starter motor wise all is dead". Is the starter getting power? When the key is in the start position does the starter make any noise?
Test for power at the large wire at the starter, if you have 12 volts test the small wire with the key turned on to see while the key is turned there is 12 volts. If you have the 12 volts then possibly a starter is bad. If not see why there is not any power flowing to the starter. If the car is an automatic check the gear position sensor. Read any and all codes in the trans and engine control units. Make sure that the alarm is off use the remote or cycle the key in the left door lock. Will that turn off the flashing LED light?