I have a 97 f150 4.6 auto with viper alarm,,been fine forever ,ac seized a month ago havent changed the belt and idler yet. The other day went to start it cranked real slow tried again just click then locks went up & down alarm goes off,,and no start,towed home assuming bad connections cleaned them up,,same thing,crossed solenoid same thing,,any ideas anybody?

 

First question, how old is the battery? Secondly, has the altenator been tested?

 

took the battery down to battery store they tested and said is fine,alternator replaced in 2011,,,i tested voltage from turning key dropped from 12 volts to 5.8 next step remove starter sand test

 

starter tested ok,replaced positive cable,was broken and corroded new end on ground at battery cranked once now just click click,,,guess next ill replace the whole cable

 

Crank click click sounds like a battery either bad or not charged possibly from the bad cable.

 

If a battery drops half it's voltage under load it means one of 2 things, Short in starter or 3 bad cells in the battery. You said the ground cable was bad which would make the charging system not work properly. Charge the battery up first and see if that works. The battery may be bad from being run down to low.

 

Most likely battery. 11.9 to 12v is actually a dead battery. Charge and battery test (conductance test is better than load in many cases, done free at Walmart). Be sure to fully charge battery prior to test for most accurate results. Be sure to retest charging system once battery issue is resolved. If battery is good I would expect from 13.8 to 14.2 v charge output. Do not test at idle but at aproximately 2000 RPM.