Key Off Issue

[xohcef]

So truck runs fine and everything sounds/operates as it should while it's running. Once I idle down, turn the key off and remove it from the ignition is when it starts givin me fits. The truck will sit as it should for a second or two but then the (main relay?) or some kind of major switch starts acting funny. It turns on for a few seconds and will run the electric fuel pump, parking brake light, wait to start light, water in fuel light, voltage gauge and oil light, then shuts right off for a few more seconds. On for a few more then off. I do not know what is going on with this thing. I keep reading about voltage regulators going bad on these trucks but I'm thinking more along the lines of an ignition switch? Just because it's doing this while the key is off and out of the ignition. Anyboyd had any experience or know what might be happenin in my CTD? Thanks in advance guys.

[ellis93]

What year is your truck?

[xohcef]

93, 2wd 5spd if it matters. There's a wire coming off the positive terminal that has a small plug connection then off that theres two wires that split off that. If I disconnect that the madness stops, can anybody tell me what that wire supplied power for?

[Tacoclaw]

Does it have any sort of aftermarket anti-theft that you know of? Or one of those remote start setups?

I would ask if it had any suspicious non-factory wiring, but I've never seen one of these trucks without any.

[ellis93]

Look in the sticky links,I posted up wiring diagrams awhile back and they ended up there.
On my truck, there are two small wires that are taped together,their for the grid heater. There is also one pinky finger sized wire with a connector in it,that one basically feeds everything except the starter.

I've had the key switches do crazy stuff just not what your having happen. I'd look around for what taco said.

[xohcef]

Alright I've found the schematics and have chased down to the ignition switch. So ill mess with that after jury duty

[xohcef]

So I bought an ignition switch and a key/tumbler assembly swapped em both in and the problem still exists. Any other ideas guys? Can anyone tell me where all the important grouund spots are?

[welderboy250]

Iirc the plug u were talking about, connects the brown wire to the starter solenoid and the red wire is for, amoung other things, radio memory. Hope this helps

[xohcef]

Well the system is on the fritz. Everytime I unplug something and or plug it back in sometying else wigs out. Now the fuel pump has quit cycling while key is off but now I'm getting a bunch of randomly flashing dash lights while the truck is running. Any thoughts on this being an ecm?

[Tacoclaw]

For the grounds, check the big one that comes directly off your negative post and runs down to the front, drivers side corner of the engine. Also coming off the negative post, there should be a little wire crimped in there that goes either up to the core support or to the drivers side fender.As far as I know, that little wire is pretty much the only real body ground on the whole truck. I'd try taking them both off, cleaning wherever they sit, and smearing copper nev-R-sieze all over everything before I bolted them back up.

It also wouldn't hurt to run another wire directly from your negative post, through the wiring harness, and have it screwed under one of the bolts that holds your voltage regulator on. That'll not only give you another body ground that's even closer to the cab, but it will also make sure your voltage regulator has a good ground so it can do it's job.


I've always heard that if it's an electrical problem that just doesn't make any sense at all, it's a ground.

[xohcef]

I have already pulled the one to the front of the block, sanded a clean spot and re installed it. Same with the small wire running to the core support. You say run a wire to the regulator but as Ive read the regulator in a 93 is integrated into the ecm correct? Might that be something I'd also look into?

[xohcef]

And I guess I have too add that I did a bit of welding on the hitch area but with the negative cable unplugged. It didn't start doing this til a few starts after the welding was completed. Sound like a voltage regulator/ecm?

[Tacoclaw]

Whoops, sorry. I didn't think about that when you asked if it was an ECM problem. I don't have any actual experience dealing with the ECM trucks, so I doubt I could make many more educated guesses about it.

[xohcef]

Anymore ideas anyone? I'm leaning towards the ecm or body control module right now, whichever you guys call it. The reasoning being I did the welding and it rained here pretty good on the same day. So I'm thinking either the welder got to it or the water did since its located in the FL fender correct