I replaced the head gaskets on my 2003 discovery , after I got everything together , the engine spins but will not fire up, the four way flashers are flashing and wont stop even if all the doors are locked or unlocked . Everything Ive looked up on this says that the immobilizer needs to be reset with a code . How do I get this code or can anyone tell me what to check next .

 

Check the inertia switch, it's on the back firewall passenger side. There is a rubber cap on it, push down in the middle.

 

I was thinking the inertia switch also.