DISCLAIMER: I posted this on another forum but have not gotten any help, so came here hoping for a better response. I know - long weekend all the really knowledgeable people are probably out wheeling instead of hanging around answering questions!
But if this makes me guilty of "cross posting", go ahead and whack me appropriately.
Anyway, here goes:
I pulled into get gas about a week ago, and went I went to start up, no go. Turned over fine, but I didn't seem to have a spark. Found the IOD fuse was blown. Bought one at the gas station, fired right up, and away I went.
Went into town Saturday to get a part for another vehicle, and couldn't start. Checked the IOD. Sure enough, it was blown. Replaced it, and it blew again before I even got the key to the Start position (son was watching it for me). Replaced it, and it blew immediately.
Towed the Jeep home.
I've done a LOT of searching on various forums, and it's clear the IOD (Ignition Off Draw) fuse is involved in a lot of circuits. TOO many - this is lousy
Since I can't get my hands on a decent diagram (yes, I'm going to buy the FSM!), and I'm therefore shooting in the dark, I started listing what I know about the Jeep that might
be related to an electrical problem. The only thing that is NOT stock is the radio, and the only electrical problem I've had is the door locks & window switches.
When I got the Jeep, the window lock switch on the driver's door was broken (floppy loose) and the switches on each door didn't work, as if the broken switch were stuck in the "I'm not letting anybody else open these windows but ME!" position. Also, the electric door lock switches on the driver's and front passenger doors were inop. (No electric door lock switches on the rear doors.) I had gotten a replacement switch assembly from a junkyard, and it all looked identical, but it didn't work at all, so I put the old one back in and have just been running that way.
I remembered that, last Tuesday, I had tried fiddling with the driver's door lock switch just on a whim, and it worked. This was a surprise. The next time I tried to start the Jeep (about an hour later, at the gas station) was the first time it failed to start, and I found the IOD fuse was blown. Replaced it, drove away, and was fine until yesterday.
Hmmmm. Messed with the door lock switch, and then couldn't start.
What would that have to do with the ignition system? Well, okay, it's something to check, anyway.
So, I pulled all the door switches, unplugged them, and replaced the IOD fuse. It didn't blow. Started the Jeep. No problem.
Not so fast.
Since the door switches seemed to be the source of the problem, and I had them all out, I decided to clean them up and see if I could make sense of the pinout and find out why that junkyard switch didn't work. I disassembled both driver's door switch assemblies (mine & the junkyard) and compared the innards. I can't see any difference. I measured the individual switches on both and they seemed functionally identical (measuring from pin to pin with the switch in each possible position). I replaced one of my individual switches with one from the junkyard assembly (because it fell apart when I took the whole assembly apart), and I also replaced the window lock switch, since mine is broken. (That didn't help - the j/y window lock switch is ALSO inop. Both show zero continuity (open circuit) in either position. I've seen a lot of posts about this, so this was obviously not one of Jeep's finer design features.
Cleaned up the parts, put it all back together, and things went downhill faster than an avalanche.
Now I can't roll up any of my windows, and the Jeep won't start.
Ah, but that good old IOD fuse is just fine!
In fact, every fuse in the beast is fine. I have checked every single one
, in the PDC under the hood and the panel under the driver's side dash. All good.
I have also metered every single pin of every single switch
on the driver's door switch assembly. Except for the window lock switch, all are working properly. All are 6 pin, double throw switches. All 5 of them (1 for each door window, one for the door locks).
Can anyone help out with a diagram of the power window circuits?
Better yet, give me a clue about how the power windows might affect the ignition circuit! That makes NO sense to me!
I'm looking online for a service manual - the real deal, not a Chilton or Haynes, but that will take a few days to get here. Meanwhile, I could sure use some help.
I know my way around electricity (I'm an engineer - it's what I do), but without a circuit description or a diagram I'm shooting in the dark.
Ah, what a great way to spend a long weekend, and I have to get to work tomorrow!