My truck does nothing when you turn the key. lights are on lots of electrical power but turn the key and nothing. I have had this problem for a few years and I would shift down to neutral and back up to park a few times and then it would start and run like normal for weeks or months until it does it a again then I do the same routine to get it started. But last night the shifting fix did not work even after 45 min. of trying it.I have an appmt. for Mon. morning with the dealer but would really like to be able to fix before then or at least figure out what the problem is so I can save some diagnostic time and money from the dealer.
any suggestions?
thanx Rod

 

anybody have any ideas???? I am very open to suggestions!!! Just shout them out . don't be shy!!!
thanx Rod

 

neutral safety switch comes to mind

 

Check for 12 on the solenoid wire of the starter while you are canking it. If you have 12volts, you need a starter.
If you don't have 12 volts, check the IGN A 40amp fuse in the fuse panel, also finnd the starter relay in the fuse panel and swap it out with another relay(usually the horn relay works fine). Also look at the instrument panel fuse box. There is a 10amp fuse in location 8 labelled CRANK.
If that doesn't work, go to the tranny,find the neutral safety switch(where the shift linkage is connected the the trans), and test for 12volts during crank on the ppl\white wire. That is the wire that feeds the relay. If you have 12 volts, the problem is either a broken wire between here and the relay, or a problem with the relay power or grounds.
If you don't have 12 volts, check for 12v while cranking on the purple wire, that wire comes from the key....If you have voltage, replace the neutral safety switch.
If you don't have 12v, go to the ignition switch inside the vehicle and test for 12v on thered wire(s), If you don't have 12 volts, check that fuse under the hood again, or find the broken wire to the switch.
If you do have 12 volts, check the yellow wire for 12v during crank. If you do have 12 volts, find the broken wire between the switch and tranny, also re-check the crank fuse in the fuse box inside.
If you don;t have 12v, replace the ignition switch.


If you follow this diagnosis, you WILL find the problem in probably less than an hour.
You can use a test light or a voltmeter for diagnosis, doesn't really matter

 

thanx Shawnvw,
I am working tonite but i will work on it first thing tommorrow and I will let you know how it went. Thanx again!!!!! Rod

 

sure enough it was the starter.Needed the truck asap for the kids so had the dealer do it in an hour or so. the info I passed on gave them a great head start on diagnosing the problem.
Thanx Again Rod

 

your welcome...glad you got it fixed

 

Im having this same issue with my '97 Z71, Im going to try to follow your advice. But I also noticed that my light for the gear selector only comes on as I turn the key from off to on, and then cuts out. Also, the fan blower wont come on, and it when I shift into 4x4 the light wont stop flashing, meaning its not working. This all happened after I replaced my intake manifold gaskets, I haven't been able to start the truck since I finished the job, but Im pretty sure that had nothing to do with this. I've replaced the actuator in the front diff before so thats no big deal, but why is this happening now? Could it be because the truck is not moving? Everything was perfectly fine when I last parked the truck, before the repair job.
Thanks,
George

 

How are the battery cables, change the battery cables,while you're at it look at the battery cables, and while you're in there, check out the battery cables.

And don't forget the engine to frame ground strap.

This is a 12V DC system. When you start to lose a good ground to the entire system, single systems many times many times stop working first.Bad cables will eventually eat your battery, alternator and starter, which is why many mechanics who are aware of this leave them in. It ensures them repeat business.

 

No, we've "deca-checked" all those things, me and several other guys who usually mess around with trucks (with success) are all baffled here, its definitely not one of those "wow Im a moron, how did I not think of that?" situations. Thanks for the advice though!