Savonplay

Seems sunroof is on the fritz. While driving or sitting in idle the sunroof slides all the way open without me touching it. It's a bit annoying. Has anyone actually fixed this issue, a side from just pulling the fuse? Thanks in advance. It's a 2003 ls430 ultra btw.

sushiboiii

iTrader: (1)

check that video out

ibrahim83

Check the fuse box in the trunk for signs of water or water damage.

Arcturus

I had this too. I pulled the fuse 5 years ago and never looked back. You could check out the connector and the battery. These cars start acting squirrely when the battery is getting weak.

tiger02

Mine was doing this a year or so ago. Did a lot of reading here, changed the battery as it was about 6 years old and hasn't done it since. I did this first as it was the least invasive, and the battery was old. Weird things happen on these cars when the battery starts to go.

BigBoomer

It's the CANBUS that causes the weird problems when the battery gets low. Since very few of the accessories are controlled directly, they all communicate via the CANBUS. When the battery voltage gets low, the CANBUS voltage also gets low and this leads to incorrect signals being read and weird stuff happening. Later CANBUS systems can detect and avoid this but the early 2000's stuff couldn't. My 2001 S-Class Merc would often open the passenger window, turn on/off the radio, open/close the moon-roof, and once even opened the trunk lid (at 70Mph) when you started it or sometimes just pressed a button. The LS is WAY better than that Merc was but is still susceptible. It could also be a weak spring in the moon-roof button or some dirt in the contacts.

VWTim

There is also some type of humidity sensor that can trigger the sunroof to open. I was doing an ozone purge on the car with it running and the windows started to fog, I left it along idling and came out to the sunroof open. It did it twice to me before I turned the defrost (AC) back on and all was well.

cyclehead

2002 UL. Mine started doing this early today. The windows all roll down and the moonroof opens itself, while beeping. It did this cycle about five times while sitting unattended in my garage. I thought one of the remotes might have been malfunctioning, sending the "unlock" signal, so I carried both keys to the opposite end of the house - far out of range. The car continues to beep and open everything up. I'm putting the car battery on charge now and hoping it's just a symptom of a low voltage.

cyclehead

Wife has charged the battery, but the mystery continues. I'm thinking of disabling the "auto open" feature using my copy of techstream (feature where the moonroof and windows all open if you hold the unlock button). But I'm concerned that won't fix this problem. The parking lights flash and it beeps every time it starts one of these un-commanded sequences. Which would say that if I disable the windows/moonroof, the car will likely still keep beeping and unlocking itself. I'm open to suggestions!

Kansas

The problem could be in one of the remotes. I suggest that you remove the battery from one of the remotes and see if the problem stops. If it doesn't, put the battery back in the remote and then remove the battery from the other remote to see if it still happens. How far is the "opposite end of the house" from your car? I've found the remotes to sometimes but not always have a range of over 100 yards.

This problem can also be caused by a dreaded disease called "TPS" which is Tight Pants Syndrome. I've opened windows, doors, trunks, hatch doors, set off alarms, etc. on Lexus and Toyota vehicles numerous times when something in my pocket pressed against buttons on a remote.

cyclehead

Thanks for the suggestions. I charged the battery again over night, plus ran techstream and turned off the “auto open moonroof and windows” feature. If it ever does it again, the doors will unlock but not open up everything! Since I charged the battery it has not happened again. I plan to replace the battery very soon.

I also changed the “trunk open” and “passenger door unlock” settings. Both were aggravating with factory settings. Now they do their job with just one press of the remote control.