Mitsubishi galant 2002 - Will not start, even with jumper cables. When turned on just hear one click noise, never had any problems till today. Hook up a newer battery and same problem, cleaned the battery terminals didnt help at all.

first item is the battery or battery cables.there are battery cable repair kits that replace battery clamp and about 6 inches of cable.

you have to check spark from the plug....step1 pull out one of the plug wire step2 put one spark plug into the plug wire. step3- clip the plug body with jumper cable and the other to the negative(-)terminal step4 start the car and see if there is strong spark on the tip of the plug

Is your turn signal or hazard flashers on? The flasher makes a clicking noise. While it is clicking see if you can find the source of it.

sounds to me like u need a starter

sounds like alternator check sparks and wires as well if not if you hear a clicking when you turn the key its the battery

Sounds like a defective starter solenoid, if the key was the issue you would hear nothing.

my galant does the same thing i was told its the 02 senors

Check and clean the ground on your battery cable. Also charge battery even if is new. Starters use all the amperage a fully charged battery produces to turn that starter. Make surecables are clean and tight :)

I would guess your starter is shot. That may be the clicking that you are hearing.

replace your battery