Bmenx2

Hi, I hope you guys can help me. I have an '03 LX with about 44k on it. We had heavy rain and wind here in NJ last night and today. I drove home tonight with the lights on, parked the truck shut it off, set the alarm and went into the house. About 15 minutes later the parking lights came on and stayed on. I tried to shut them off manually and by using the auto light function, etc. I took a ride in the truck and the same exact thing happened. I am going to disconnect the battery overnight.
Anyone have any ideas?

Bmenx2

Update on this situation:
I reconnected the battery today and started the truck and turned on the lights, radio, etc. Everything worked as it should – the lights are in the “auto” setting and they turned off, etc. There was no wetness on the carpet or dash and nothing seemed wet under the dash.

I spoke to a long time Toyota/Lexus service person that I know and he mentioned the following:
- This issue could be wetness/corrosion in the integration relay. He mentioned this is the number one contributor to the parking lights coming on without manual activation.
- If there is corrosion, eventually, the corrosion will spread to other areas in the box. This could cause important circuits to not respond properly, or not at all. This is not something I can wait on if it has corrosion in it.
- If an aftermarket alarm is installed, it could be that as well - no aftermarket alarm.

I asked him what I should search for and he told me the following:
- Water intrusion into the fuse panel and/or corrosion inside the integration relay (sometimes called the 'body computer').
- Check for wetness in the driver side of the instrument panel, where the fuse box is located.
- The windshield could be leaking, the sunroof drains could be leaking, anything that allows water in this area can and will cause this condition.
- I should water test the windshield. It needs to be water tested while someone examines the area under the dash for wetness, etc.
- I may need to extract the fuse panel to determine water intrusion.
- In short, something is activating the circuit to the park lights. The device he mentioned is between the switch and the lamps.
Stay tuned for updates.

ggebhardt

An '03 LX with only 44K on it would be rare indeed. The LX470 was always my favorite with silky smooth operation! I hope you find your problem

Bmenx2

Thank you! I appreciate it. I really like the truck and was lucky to find it. It's at the dealership now and looks like "water intrusion" under the driver side carpeting. They are searching for the source of the water.