2006 RX330 wierd electronic problem (update 04/11)
 

The GF called from work that the car's alarm has been going off all day. When she goes to turn it off, it doesn't work until, she unlocks the car manually, start it and then shuts it off. When she comes out and closes the door, the headlight and the radiator fan comes on for a full 2 minutes, and then shut off. During that time no other controls are working, can't lock the doors, open the rear hatch (manually or by key fob) or do anything else but wait. Can anyone help, please?

Update 04/11:
Spring deluge of rain, meant that this started again. This time, it settled into, turn the car off, the DRL stays on, the radiator fan comes on and stays on. No response to key command. Ended up just disconnecting the battery overnight.

The next morning, a trip to the dealer, symptoms persist in the drive in bay where the SA processes the car. They take into the shop, 3 hours later, the SA comes back and says, they couldn't replicate the problem. The lease is due in two weeks anyway, I was going to buy off the car since I had $5K in down payment in, but now, no way. I asked him to produce a clean service record, and perform a lease return inspection while I talked the sales people. Walked away with a 2011 Touring Package.

I'd ask how old the battery is, because that's usually when the electrical gremlins start to appear. I've had quirky things with my RX300 over the years in the electrical area and the first thing I'll do is pull the battery cables for a few seconds and then reattach and see what occurs.

Battery was replaced Jan 09. First thing I did, when I got home is check it, the positive terminal was fairly dirty with a white greenish powder. Went to the nearest canadian tire (autozone equivalent) and bought brand new battery and installed it. the battery came to $125 after taxes and core credit, but given canadian winters, If I have any doubt about a battery, out she goes. Cheaper than a tow or frost bites waiting for one.

Update: Overnight, the alarm went off twice, until I just left car unlocked. :sad: Took it to the dealer this morning, drove into the service bay and on cue, the headlights and radiator fan came on. Checked in, and the lady that was checking me in got the head service technician to look at the file. He asked some questions, and we went back to the car. GUESS WHAT, couldn't make it happen again. :egads::egads::egads:

They hooked it up and read a bunch of body codes, but since they were all in the history, there was really nothing else he could do. He did ask for me to bring the car in and leave it overnight for them to monitor it (for the alarm) and also, he thinks there must be some moisture in one of the wiring harnest, due to the deluge of rain we got in the last few days.

Any help by anyone is appreciated. I will post the body codes when i get home tonight.

:uh::uh:

Here are the body codes:
B1206: P/W Master SW ECU Communication Stop
B1208: Right Seat (Pass. Seat) Mirror ECU Communication Stop
B1209: Left Seat (Drv. Sea) Mirror ECU Communication Stop
B1261: Engine ECU Communication Stop
B1262: A/C ECU Communication Stop
B1273: Sliding Roof ECU Communication Stop
B1281: Airbag ECU Communication Stop
B1287: Back Door ECU Communication Stop
B1294: Steering Lock ECU/Immobiliser ECU Communication Stop

All seem to be related to communication stop to the ECU, Since the ECU is recording them, I doubt that the trouble is the ECU itself.

Well, if there was some moisture that could cause an issue with the electrics. I had an issue the other day with my brake light and some dinging (sound). We had a lot of rain here due to the tropical storm. Today, problem is gone. However, some moisture could have gotten trapped in there. For instance, one time on my rear corner lights, I had some water seep in there by the connection...bulb went out...I checked it and there was some gray sponge like material (an adhesive trip) and it was extremely wet and only after I cleaned the area up and resealed it, did the bulb work again. They're probably going to have to dig around in certain areas inside door frames and the like to make sure.

Am guessing the previous battery tested fine but you went ahead and changed anyway? Or, did you just change it out just to be safe as you stated?

Changed it anyways, just to be safe. Still living with the problem. But not as bad today, only the fan/headlight came on, the alarm didn't trip. Does anyone know if the various sensors listed here share a harness or if their connections go through a particular area of the frame where moisture could have gotten in?

Electrical problems are a nightmare! Hope you get it worked out. Let us know what happens

I updated the original post with the latest. I ended up taking a loss on the car as I didn't want to end up with an undiagnosed, intermittent electrical problem. Besides, the future troubleshooting/repair costs and aggravation could turn out to be more than the current loss, so que sera, sera. So Long RX 330.