I accidentally took the rental Wrangler key fob for a swim in the hotel pool for about an hour this weekend in Hawaii. It was dead, but I brought it back to life and saved myself the $250+ fob replacement fee. But first, I tried opening the Wrangler JL with the flip-out key. The alarm went off, and pushing the fob to the start button did not start the car, alarm still blaring, my littl'un screaming and freaking out. I had to relock the car with the key to get the alarm to turn off. So I did some internet searching...
I went to Walmart and bought 91% isopropyl alcohol ($3) and a small screw driver set ($6.50). Then I went to Best Buy and bought a 2-pack of CR2450 batteries ($10), because the battery was certainly drained after being shorted out for an hour. Step 1: take the old battery out and throw it in the trash. Then, I completely disassembled the fob, and even though it looks like small torxs screws to get the circuit board out, the very small flat head worked the internal screws. I even pried out the front push button panel, which was actually fairly easy to do. Everything got an alcohol bath and then dried with the hotel-room hair dryer set to warm and low. I was slow in drying the circuit board, multiple short drys, didn't want to damage it with heat. Lastly, I installed one of the new batteries, the second being my backup, because it is not a common battery.
That did the trick. But there is more... I was wondering why the flip-out key wouldn't flip out when we picked up the vehicle. After being inside the fob, it's because this fob had been in sea water before, and the preload on the rotary spring was not properly reset. It's easier to put it back together without the preload, so I did that. I know it was in sea water because of corrosion on the microprocessor terminals. De-water your drowned fob with 91% alcohol ASAP, especially if it was in briney waters. Clean it out soon, or pay later.
Conclusion: Once the battery is removed and you have everything apart, don't be bashful about squirting 91% isopropyl alcohol in and over everything to displace the water. Then take your time drying it out. The whole process took me 4 hours, but that's only because I jogged 11 miles to get to Walmart and Best Buy and back to Waikiki. It was a nice run, 8:30 minutes/mile through the entirety of Honolulu. Would have been more fun to drive the Jeep during that time instead.
