Interior light and intermittant Door Open warning light Problem.

[Tech21]

Hi and greetings from New Zealand,

2004 Avalon Grande Mk3,
Model.. MCX10R-BEPEKO
Trans... A541E
Engine. 1MZ-FE 3.0 lit V6
VIN...... 6T153XH1006037905
100,000km (60,000miles) with FSH

Built in Australia not the USA

So.... Interior light has stopped working when doors are open but works fine off the roof on/off switch.
Sometimes the Door Open light stays on when all the doors are shut but dimmer than normal (goes to full brightness when any door is opened) and I can't lock the car when this happens as it is sensing an open door.
Yesterday I locked the car with the remote and an hour later the alarm went off and the dash "door Open" light had come on and (presumably) set the alarm off as it thought a door had been opened.
I haven't been able to establish yet if the dash 'door open' light glows with doors shut only when the weather is damp but it is looking to be probable, but the interior light isn't working at all off the doors.
Also the "Door Open" dash light doesn't work when the boot (trunk) is opened, but I'm not sure if it ever did or not.
I read somewhere (can't remember where I saw it) that the timing of the duration of interior light is somehow programmable from the car, is this True/False??
and if true could the flat Battery I had a month ago have any bearing on why it's all screwed up, like the radio was. It went totally flat after 6 days of car not being used, was replaced with a brand new Battery... oddly the old Battery came back up to full charge on Calcium charge setting on my Charger.

*Note on the radio (might be of use to somebody).* After the battery went flat the Security code for the radio was being asked for and I didn't have it. I read somewhere that the code was the last 3 digits of the VIN, I thought this was BS that someone had made up but when I tried it it worked, but really I suppose it would have taken any 3 digits as the previous owner was very unlikely to have set up any security on the radio especially the last 3 VIN digits... I also can't believe that a Toyota factory would spend time and money having someone program all the radios with the last 3 VIN digits.... Maybe the first time it asks for a code and it hasn't got one set up any 3 digits will do and that becomes your security code from then on.

This door open warning light and interior light no longer working appears to be a very common problem on most Toyota models (according to the internet) but nowhere is there any definitive answer on the cause and how to cure it.

So then, Does any one have any idea on the probable cause and the cure for this problem?

I've done all the standard stuff fuse, switch in the right place etc....

Cheers and Thanks in advance
T21

[Phil T]

Bit late but if this is a common problem. Take the door switch off and check for corrosion and poor operation. WD40 it and operate it buy hand see if there is consistent switching. The rubbers often get out of line and become squashed over the switch causing problems.