I am having an issue with my 2006 HiHy.

I have noticed off/on this issue, though it is more prominent now. Whenever the car gets wet--car wash or rain--the radio and NAV screen will stay on even after I shut the car off and take out the key. At first, it would only be a few seconds or so.

Recently, I returned from Chicago to find my car dead at the airport. It was jumped and ran fine, but was dead again the AM. I took it to the dealer and they found nothing. I took it back the next day for the same issue. They kept the car for 3 days and found nothing. Of course, by then it was all dry.

Today, it poured over here in the NYC area and again the car in not shutting off. I have left it overnight in my garage with the hood up. I need the car for the next few days so I can't bring it to the dealer. I plan to bring it back later this week.

Anyone else seen this problem? Any ideas?

Nobody?
FYI, I am also getting a background static on the radio.

I'm no expert and I do not know the wiring but..., I would guess that you are getting water in the cabin/around the firewall from a clogged drain. It could also be a drain tube dislodged from the condensate pan of the A/C (This happened to me in my other car. It affected the radio as well.)
You have a short that is most likely caused by water coming from above the car, as opposed to splashing up from underneath. The tough question is where?
I'd check for the obvious, water in the cabin and debris in the drain under the wipers. Other than that, a car wash followed by immediate inspection from a mechanic possibly with the dash opened up for easy inspection.
Good luck.

Update...Toyota elected to replace the entire center console with the radio/NAV system.

After that was done, it was noted that the keyless entry did not work. When they investigated that, they found standing water in the right rear corner submerging the wiring and leading to damage. They need to replace that wiring for a cost of $1700!!! $700 for parts. $1000 for labor!!!!!

Now how did the water get there? Toyota is claiming that there is a missing nut on a bolt in behind the tail light. This led to the tail light being loose and allowing water into the car.

The original theory was that an accident led to it getting loose. However, the only accident I had a was a very low speed collision with a tree backing up a dark driveway. This lead to a crack in the rear bumper. I had the bumper replaced nearly TWO years ago.

Toyota (the dealership) is claiming/theorizing that when the bumper was replaced, the tail light assembly was re-assembled improperly.

I am paying for the repair, but I intend to find out if the tail light was even touched when the bumper was replaced? Does anyone know if they would have to remove the tail light to replace the bumper?

Below is a pictures. More can be found here: http://www.msj3.com/2007/highlander_water/

Any other ideas?

P.S. I still don't know if the original issue is fixed. Toyota is claiming the wires affected by the standing water should not have been involved in the original problem. The car has been in the shop a total of 3 weeks for this problem.

Thanks for the update. It's great news that they found the source of the water. The tail light may have been removed, especially if there was damage and/or painting involved on that area.
When Toyota replaced the console, did they replace the radio/nav as well? If so, did they replace the amplifier?
I looked at your pictures (Nice by the way) and noticed that the compartment which was flooded contains the JBL amplifier for the radio system. If you are still having problems, I would look back there for more damage.

I am not sure, but I tihnk they replaced the entire center console. I can ask.

If the body shop did screw up (pun intended), there are new questions?
- How do I prove it?
- When do I notify them? Before the repair is completed so they can assess the situation?
- Are they actually liable 2 years later for the damage?

Update:
- I spoke with the dealer and asked about a partial repair of the wiring, i.e. replacing the caps. He said Toyota does not allow that as there may be unseen damage to the wires. Also, the corrosion seen will lead to wire damage.
- He was certain the car would be fixed after this repair.
- I spoke with the body shop. They said they have no idea if they had to open the tail light to replace the bumper. There is no note that it was done, but he said he can't say with 100% certainty that it was not done.

So, it looks like I am paying $1700 to get my car back with no one to blame. Toyota will claim it is the body shops fault. He will deny it. Sounds excellent.

Although the expense is unfortunate, having the car back good as new with accurate knowledge as to the source of the problem is priceless.
You may be able to re-open the original insurance claim (If there is one) and add it as additional damage. Just a thought.
Also, you still can consult an attorney and commence a small claims suit. It all depends on whether or not you want to invest the time & money.
BTW, I had a similar repair on another car. Labor alone was $5,000 to run a new antennae cable and I lost use of the car for 5 weeks. That's another story though...

Did you use a repair shop that was recommended by your Insurance company. With my insurance company, if you use their repair shop they warranty the work for the life of the vehicle (while you own it).

I would start their.