'98 Expy Door Ajar Light Problem - WD40 doesn't work

[andrewmh]

To all:

Thanks in advance to all for reading and to any who might be able to provide some help.

I have a '98 Eddie Expy, and I've had the door ajar problem since about March of this year. After reading this forum, I've applied WD40 to the latch on the doors themselves multiple times. I've tried opening and closing the doors, but nothing seems to solve the problem. My solution has been to remove the fuse, but then I can't use my windows.

I'm guessing then, that whichever switch stuck is broken. I'm not really pumped about taking each door apart to find out which one it is. Does anyone know of any method for determining which door is broken in advance?

One last fact: while the dome and other interior lights stay on, the running board lights will turn off as soon as the doors are closed. Do you think I can assume that it is either the window or rear door latch switch?

Does anyone this I'm applying the WD40 wrong?

Thanks again,

Andrew

[Johnny Mullet]

In my opinion, WD-40 is not a good penetrant. It probably water-proofed the latches, but not fixed anything.

The best penetrating oil in the world is PB Blaster and I love this stuff! Simply open the door, saturate the latch mechanism, and start slamming the door open and closed. Do this to each door including rear hatch.

If that does not work, then you have a really bad switch. A dealership can hook up the computer and monitor each door with it to determine what switch is bad, but it will cost you a diag fee.

[andrewmh]

Johnny and others:

I tried the PB Blaster but that didn't work either. I coated all the latching mechanisms and tried closing the doors multiple times.

Because the running lights don't have a problem turning off, I took a guess that the broken latch was in the liftgate. Bad assumption. After taking the latch mechanism off, and trying to figure out where the plunger switch was, I was still in the dark (or light, I guess). After reattaching, I noticed that closing any one of the doors, liftgate, or rear window, turned the dome light off.

So, there has to be a working switch in each of the doors, liftgate and rear window, or the running boards wouldn't turn off, right?

Given that assumption, I removed the fuse and applied a voltmeter to see if I had a short somewhere. No dice, I read only a really tiny voltage differencial and even that went away.

Two other facts might make a difference. The rear window wiper won't work (leading me to believe the multiswitch might be a problem) and I can't keep wiper fluid in the thing. I haven't watched for leaks, but perhaps they could be related. All I know is that a gallon of fluid lasts less than 24 hours.

Any thoughts?

Thanks in advance for reading this and for any help you could provide.

Andrew

[andrewmh]

UPDATE

I also tried starting the truck and then opening the doors and stuff one by one to see if the warning beep went off. I figured where the warning sound didn't go off, the switch must be stuck. But all the doors, the rear window and the liftgate all made the warning sound go off. I'm starting to think that this problem isn't related to a switch at all.

Anyone have any ideas? Is this a multi-switch problem?

[hotwire1]

My mechanic told me to check the door that gets used the most first. At this point I still have the driver's door switch disconnected. The only disadvantages to that is that the interior light does not come on when that door is open and the headlight on/ignition off warning buzzer doesn't work.