engine wonlt start after replacing ignition switch & starter on 2005 GMC Sierra 1500 HD

i replaced the ignition switch, then the starter, and now it won't start. what can i do without an code reader to point me in the right direction as to whats wrong.

by in Phoenix, AZ on September 06, 2010
1 answer
ANSWER by , September 06, 2010
try crank sensor