Mitsubishi Repair: 1995 MONTERO WONT START BATTERY FINE, radio works, autozone

Question
I replaced the battery and cable, I get one click, it wont turn over, any suggestions,  I am beginning to think it may be the anti theft device.  

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-----Question-----
I TOOK THE BATTERY OUT TO CLEAN THE CABLES IN MY 1995 MONTERO, THE RADIO AND LIGHTS COME ON. BUT THE TRUCK WONT START, NO NOISE AT ALL
-----Answer-----
Cindy: Did the truck run before you took the battery out? If so then you most likely did not get the cables tooked back up right. Or you have a bad cable or your battery is bad. As long as the lights and radio works, then I think one of your cables is not tooked up tight. But then I would have the battery tested, it could have enough juice in it to run the lights and radio but not to turn the starter to start the truck. Hope this helps and good luck!

Answer
Cindy: It could be your computer. Or a sensor/s that have gone out or is weak. But you need to get your truck coded to rule that out. AutoZone will do this for free if you can get the truck over to them. That would tell you if it was the computer. Sometimes it just goes. If you can unhook the anti theft device, I would try that too. Hope this helps and good luck!