My 02 GS300 started having a lot of electrical issues after I got windshield replaced. Windows doesn't work from driver' switches. Door locks remote no longer work. Fuel, ABS, Brake lights went on and off few times. Dash lights and gauges lights were off.
After disconnecting nagative batter and left the car for a while, the dash light and gauges lights were back on. However, sometimes it were delayed for few seconds before they were on. Steering wheel intermittent had issue with moving back and forth after inserting the key in. It also exhibits delay of moving back and forth when inserting or removing key.
I wonder if replacing windshield messed up all the electrical or it was just a coincidence with windshield replacement. Any help is appriciated.

 

Probably not a coincidence, maybe they sliced some wires with their sharp blades when cutting the glass out.

 

Maybe there's a leak around the windshield or a drain is clogged.

Paul

 

The water leak version is more likely. On both sides of the dashboard are relay / fuse boxes with control boards inside.
If the windshield is installed in such a way that it leaks into them, then there will be electrical chaos.

 

I just had many similar issues with all this rain. Pull the carpet back on both sides and see if you can find any evidence of moisture.

 

I am not sure what happened but the car was self-healed after parking for a day. Everything is normal now. When they installed the windshield, it was a rainy day. There was no sign of water leaking or moisture smell but the car has weird symptoms. I found someone has the same issue on IS model when they replaced the windshield. I am not sure if this is a Lexus thing.
New windshield - causing electrical issues? | Lexus IS Forum (my.is)

 

Yea. That pretty much guarantee's you have a leak. It will be back as soon as the next serious rain. You should investigate your drains before that happens. Good luck.

Paul

 

I've been driving in the rain (not heavy rain) and through car wash but didn't experience any issue. Will garden hole on winshield see if it has any leak.

 

To be perfectly honest, I don't know. I just know by reading through enough post that the cause of random, weird, inexplicable electrical issues that come and go are usually caused by water. I would first try and locate which side of the car it is getting into. (if it actually is getting into) Intermittent problems are the worst to find. You can't troubleshoot something that ain't broke right? So, here's another one. Have you had to add any coolant? Top it off? Anything like that? It could be a leaak from the heater core. But again, I am just throwing things out there without actually knowing. I'm trying to be helpful, but it's still only an educated guess.

Paul