1999 jeep wont start...loud, rapid clicking noise

i have a 1999 jeep cherokee 6cylinder 4.0

it will not start. when i turn the key i hear a loud, rapid clicking noise.

i have tested the battery and starter at Autozone and they were both good.

i tried to start the jeep with another working battery, which ended up doing the same loud clicking noise.

????????????????

It sounds like you have a bad starter relay. It is located near the battery under a plastic cover. You can follow the positive battery cable to find it. The battery cable should go to starter and the smaller wire from the positive terminal should go to the relay. To double check that it is the relay, you can by a remote starter switch at most part stores. This will allow you to bypass the relay. Just follow the instructions in hooking it up and make sure you turn the key to run (ON) then press the button. If it starts then, you need to replace the relay. Fairly simple to replace and doesn't cost much.

You must have a bad ground cable or a bad positive cable.

You said you had the starter tested. Did you take it out and take it down there?

That is why, I always recommend using a voltmeter, so you can verify if enough voltage is getting to the starter itself. The ground cable is the return path to the battery and is just as important as the positive side.


BTW, the solenoid for the starter on a 99 is on the starter itself, not on the fender like the 80s and early 90s models.