i need help asap, problem just came about with the truck

my dad took my truck to school, said the blower motor and radio didn't work on the way, went to class, came out and started the truck. it ran for a few seconds and just died. not slowly it just died in the blink of an eye. im thinking ignition switch but doesn't the interior and all that shit run off different contacts in the switch then the motor, if one went out would they all? im stumped and pissed. coil wouldn't have anything to do with it would it? I don't think any electricity flows through the coil to the inside of the truck does it? any help would be greatly appreciated cause my back window latch doesn't lock and I have a stereo worth more than my truck in it.

i correct myself, he didn't say anything about the radio he said the blower motor and windshield wipers didn't work on the way to school. made it there, came back out, started the truck, ran for a few seconds and immediately died. he said he thought it was a fuel pump fuse or something but my fuel pump is mechanical and has no fuse. and if it was a fuel pump issue, it would take a few seconds to fully die, would take a few seconds for the motor to use the remaining fuel b4 all fuel pressure was lost. any thoughts? im almost sure its the ignition switch but im still confused as to why the blower and wipers quit working b4 the engine. they both operate from the "run position of ignition switch"
if the switch was the problem, wouldn't ANYTHING that only works with the key on run quit working at the same time?

I believe there are different ignition switch contacts for the run circuit and those other items in the same "run" position. Check the wires under the steering column with a test light or DC voltmeter.

And test at the coil positive side to make sure there's positive voltage there when the key is in the "run" position.

thanx cusser, does answer one of my questions. how likely is it that both or all of those contacts would loose ability to transfer electricity within an hour. as stated the motor ran and he made it to school with no wipers or blower motor, then went to start it after class, and it fired right up he said, then a few seconds later, died. one time a while back my blower motor wouldn't work and then a few hours later it worked again. maybe my coil and switch are going bad.

When you have the key in the "ON" positions. There are three primary circuits that are powered.

1. ACC is receiving power.

2. Ignition #1 Circuit is powered. This powers the following items.
Engine Fuse: - Ignition, Engine Control, & PTC Heater plus some other optionals stuff

3. Ignition #2 - Heater Blower, Wipers, & Rear Wheel ABS (if equipped)

So when you lost your blower and wipers, then the IGN 2 circuit was dropping out. Almost certainly the switch. Then, It probably started dropping the Ign #1 circuit (wiping out ignition among other things) when he started it up.

As mentioned above, turn the key to "ON" and see if you have 12 volts at the coil. Or, you can also check to see if you have 12 volts at the "Engine" fuse, "Meter" fuse, or "PTC" fuse, all of which would be upstream of the coil and down stream of the "IGN 1" lead on the switch (your fuse's should have little areas exposed on the back of them to probe with a meter.) No need to pop the hood. If you do have good power to those, then you can start looking elsewhere downstream. But I think you'll find you have a weak if not completely open circuit there. It sounds very much like your switch is bad. If you do get 12 volts on those, try cranking and see what the voltage is with the starter engaged. If it drops down to 10 volts or so, that's probably OK. But if it drops much more than that, the switch it probably bad.

One little footnote on replacing your switch. Trucks from 86-89 have two extra small gauge wires on the back of the switch. The later model trucks don't have these. If you have a 86-89 truck, then you'll want to make sure and get a similar replacement. If you have a later model year truck, then any switch (86-93) should work since they don't need or use those two extra wires.

well, ignition switch is dropping ignition # 2. but on a good note, and a stupid note, i asked dad if he put gas in and if he was parked facing downhill! he was and that's why it wouldn't start back up. wont get fuel when its facing downhill with less than 2 gallons. i don't know who should feel dumber, me or dad. haha. heater and blower motor work sometimes if i tap on the switch or wiggle it around, so i opened it up and sprayed duster, wel see how long it lasts. i got it working tho last night and that particular conflict is because of the switch. thanx guys, felt like i was Huston trying to fix Apollo 13 from the ground cause i was trying to diagnose issues from work when my truck was at my dads college. still a little bummed that im waiting on $100 dollar part to die so i can spend half my bank to replace it. but atleast its not sitting in a parking lot somewhere. thanx again fellers.