Am very new here and do not see anything online that seems to help.
I have a 2006 Jeep Wrangler Unlimited w/ 33k miles on it…4.0 engine. Have had it a little over a year. Last Fall, it started having issues whenever we had a lot of rain. Would not crank at all. Replaced the battery and clutch switch, which seems to helped, but is now doing it again. I turn the key and all of the lights come on, but there is not even a click. If I coast it off and pop the clutch, it starts right up. Once it dries out, will start w/ the key without an issue. Have an appt w/ the dealer, but they cannot get to it until Thursday, but I have to drive to work until then.
I took it to a friend who is the manager of a garage, but he cannot find anything wrong.
There is a relay in the Power Distribution Center called Engine Starter Motor relay. I would reseat it and clean all connections at the battery and starter.
Before you do anything try the following: Any time the Jeep won’t crank put the transmission in neutral and try to start it again. I have a '08 Wrangler Unlimited and the neutral safety sensor is problematic. Occassionally it refuses to start while in Park, throw it into Neutral and it cranks just fine. I found that out after replacing the battery needlessly.
A faulty switch or relay in the starting circuit does sound to be the trouble as the others have stated already. You could install a temporary bypass switch to the starter solenoid in case you need it to get you going and until you find the problem.