IOD Problems??

[loneleix]

I have a 2008 PT Cruiser. The interior lights suddenly came on and stayed on. When I found and pulled the correct fuse to get them off I get a "fuse out" message on the dash which is fine but the interior and dome lights come on and stay on whenever the engine is running.

Doing a little research it seems that this has something to do with the IOD system but I don't know what to do next.

[heifetz17]

You removed the IOD fuse, which has nothing to do with the dome lights specifically.

The IOD fuse is Ignition-off draw. When the ignition is off, there's always still a draw on the battery, such as from the radio or clock. the IOD stops those draws while the ignition is off. The only thing the IOD fuse is acutally used for is during transport when the car is new. They leave the fuse out because the car can go weeks without being started while it's in the transport process, and they don't want the draw to drain the battery.

The IOD fuse serves no other purpose. You're radio most likely doesn't work either since the fuse is out. It disables certain vehicle electronics while it's out.

I would simply remove the bulbs for the dome light until you can get the problem corrected.

[loneleix]

Actually.... I removed the interior light fuse. The lights now go out when the car is not running but come back on as soon as the engine is running and stay on until the engine is killed. At least now I don't have to worry about killing the battery when the car is not running.

The IOD system seems to be connected to several different circuits in the vehicle and I checked each fuse listed as being connected but found no problems with any of them.

While I am aware of what the IOD is designed to do, I am not aware of any reason why the interior lights would come on only when the car is running even though the fuse listed for their circuit is pulled.

[loneleix]

Good news, Bad news..... The good news is that I located the problem. The bad news is that is probably is going to get worse before it gets better.

The problem is in the Light adjustment collar on the lighting control lever. I rotated this adjustment back and forth several times and the lights went off. Obviously, there is some sort of short/bad connection issue with the collar or the wiring coming through the lever. From reading other posts in here and other forums on PT's it appears this is something that happens with some frequency; although most of the problems appear to be related to fog lights.

Several weeks ago on a trip the radio quit working. It wouldn't turn on and seemed to have no power going to it. After a gas stop it started working again so I assumed there was a wiring or connector issue and made a mental note to get back to it. I guess I should have done that sooner....

Does anyone have an explanation as to how the IOD components all work together? I am still confused as to how I can pull the fuse for the interior lights yet they will come on when the engine is running???

[heifetz17]

As I've said before, you did not pull the correct fuse. You pulled the IOD fuse, which has nothing to do with the interior lighting directly.

I think you may be mistaken if you think you understand the function of the IOD fuse because you don't understand why the interior lights still work.

The ONLY thing the IOD fuse does when it's out is prevent electrical draws on the battery with the ignition off. Therefore, with the ignition on, the lights will function.

Many components are connected to the IOD fuse. How else would it interrupt electrical draws on the battery when it's removed?

The simple fact is, you pulled the wrong fuse. Try fuse 17 or 21 for interior lighting.

The IOD fuse connects terminals 7 and 8.