I have a 97 F150, 4.6L and around 105,000 miles on it. When I turn the key to start it, I lose all electrical power. When this happens and with the key off, I can hear the relays click in the fuse panels in the cab and under the hood. The battery and connections are good.

Can anyone offer some guidance please?

Thanks!

 

I know you said you knew the batt was good,and connections,but it STILL sounds like either one or both is your problem.How old is the Batt?

 

The battery is 4 years old. I have had no problems up until now. When I turn the key to start, ALL electrical just goes dead, after a short time I can have good headlights, radio and everything until I try it again. Still leaning toward the battery?

Thanks!

 

At 4 years old,your on borrowed time anyway..I suggest replacing it,and the terminal ends.if its a side post(which likely is) be damn sure the connections are clean,SHINY,and corrosion free....betcha itll crank right up

 

Could be battery or something else since you say everthing just goes completely dead. Bad battery would not go to zero volts. Do you have a volt meter that you can check the voltage at the battery with. See what it is before you turn the ignition on (should be 12 volts or very close to it) then once you turn the ignition on. If everything dies and you still have 11+ volts at the battery - there is a connection problem. Try cleaning the connections again and make sure they are tight.
Also - these early years are prone to water leaks into the fuse panel. Did this start after it rained in your area?

 

Check the ground, the factory terminals on the battery leads aren't the best. Follow the neg. lead and make sure all the connections and the conductor are solid. Sounds like you are loosing ground when attempting to start.

John

 

You were right - after checking, the battery was only 3 years old but still bad. I have never had one just go bad like that.

Thank you all for the help !

 

Most excellent,Glad to be able to assist.There is a TON of great info( and people) on this site,and Im proud to be a member......Stay tuned, were happy you are here!

 

I'm doing U Joints this weekend so I did a search for some tips- So much good stuff in there it's hard not to read them all - great site!!!

Thanks again

 

Yeah...aint it great!.......:-)