1999 Yukon wont start

[Martinez_1432002]

I am having a major problem... with my yukon... It wont start at all... It wont even crank...... I do have battery because my radio works, They checked the battery terminals to see if that was a problem everything good, changed fuel pump 6 months ago, changed fuel filter, changed ignition switch, changed some other thing thta goes with the ignition... They told me that is wasnt the starter because when they would try to start it from some place under the truck it would crank...Not the seleniod either....Cables look good....What a mechanic told me is that there is no power going in the ignition but there is some coming out..... Im all confused uts crazy.... I had a similar probvlem with it at the begginig because of the security system, and it would disable and fuel.... But then it would crank..... and the security light would come on....now nothing happens.... does not crank or security light!!!!! I need help that is my only car soemone please help......................

[handy1219]

Try to disable the security system - if you have gotten the Custom security - not the factory, cause sometime the Custom installed security shuts off the fuel pump. The starter should try @ least to crank or make some sound , when its trying to spin the engine. One thing you must know though: "There are three things working in the engine". Air, Fuel and Electricity, so obviously you are missing something there. Go one by one and check everything. Good idea to disconnect the starter and try to spin it separately..., sometimes simple oil starter lubrication gives out good results and it starts spinning.
Good Luck!