A few weeks ago, the truck would try to start sitting in the driveway with me in the living room and keys in my pocket. Also the radio and dash lights would come on and go back off. Found that part of the ignition switch had broken off, there was a plastic part sitting on top where the key cylinder goes and had a metal clip touching metal. Fixed it with gorilla tape and thought it fixed the problem for a few weeks but now when the engine is running, the starter tries to engage for a few seconds and quits. Also the radio and dash lights go off then come back on. Would appreciate it if anyone has a clue what's going on.

 

Sounds like a faulty ignition switch. May be time to replace it.

 

Replaced it Wednesday night. Battery and starter are new, and I've replaced the relay solenoid on the firewall as well.

 

Since all the main components have been replaced, then the remaining possibility is faulty wiring or the ECM. If the strange problem occurring is random then a short somewhere is likely occurring. Difficult task is trying to find it. I don't have any clever suggestions to ease that task. Maybe someone else will offer a tip.

If there is a pattern to the occurrence of the problem it is possibly the ECM. Checking the ECM will likely require a high end diagnostic scanner. May need to see a dealership for that.

 

I've read a few threads about faulty GEMs and I may try that too.

 

It is impossible for the PCM to cause this set of symptoms. GEM, fuse box or wiring are among the possibilities.

Does the phantom cranking and the dash/radio malfunction occur at exactly the same time or a random different times?

Exactly which dash lights are exhibiting the behavior?

Is there an aftermarket or dealer installed remote start installed in the truck?

Have you pulled the kick panels and inspected the grounding lugs for loose or corroded connections or body rot?

 

I haven't been able to establish a pattern yet, no dealer installed or aftermarket remote start, and it's supposed to be decent weather so I was going to remove kick panels today.

 

I've removed the fuse box and there was moisture inside once I removed the two big plugs. I also pulled the GEM off and looked at the circuit board, did not see any moisture on it. I put a generous amount of dielectric grease on the connectors and cranked it back up. I had the dash apart so the headlight switch was unplugged but the display on the radio kept going out and coming back on and the starter kept trying to engage again. Possibly the GEM is bad? The grounds under the kick panel look good, no rust. Tempted to start pulling plugs apart and applying dielectric grease to them one at a time. I also have some Flex Seal and the next warm day remove the windshield cowl and see if it is leaking. Otherwise, I am at a loss.

 

I bought another GEM but also pulled apart most electrical connections and applied dielectric grease. Have it cranked and running, so far everything seems ok. Hope this was the fix.

 

Sorry to bother you, Do you know what this component is? It keeps producing a crackling noise also power remains on accessories even after I remove the key.
Thanks

 

Looks like the relay box from under the dash.

Next time please start your own thread.

 

Where is this relay box located? I don't remember seeing it when I replaced the ignition switch and GEM. It may be what's wrong with mine too.

 

Ended up replacing fuse box under the dash since replacing GEM didn't solve the problem. Drove it all weekend without any issues.