Starter or Neutral Safety switch

[Box Rocket]

Well, I got it to start! Haven't driven it yet but several startups in the driveway have worked flawlessly. One of the NSS wires had not fully "seated" into the new plug housing and there was a bad connection there. It took going over every single step and checking every connection again to find it. But, I believe the culprit in my case was in fact a bad ignition switch. The NSS and wires were in good shape before so that was a non-issue (until I didn't get one of the wires plugged back in all the way).

But the other steps taken were not in vain. I inspected my old starter and the contacts were definitely worn and in need of replacement. Yes, I could have just replaced the contacts but it was under lifetime warranty so it was easier to just replace the starter under warranty. The battery cables may have been ok for a while longer but after nearly 30 years in the truck I don't think it was a bad move to replace them.

 

[Cruiser804]

Well I'll post this for future reference

 

[Rusty Cruiser]

I confirmed that the A/T Oil Temp, Brake, and Oil Level lamps only come on when the ignition switch is in the start position and the NSS is in park or neutral. If the NSS switch is bad or disconnected, these lamps do no light up (and, of course, the starter solenoid does not get energized). It would have been interesting to see if these lamps were coming on back when you were having your problems, Ken. If they weren't, it would have definitely pointed to a problem other than the starter.

Very interesting! I am chasing down an intermittent no crank issue at the moment that seems to be pointing to the NSS or the wires leading to it. I've always wondered why my A/T Oil temp light doesn't light up...

 

[TrickyT]

Very interesting! I am chasing down an intermittent no crank issue at the moment that seems to be pointing to the NSS or the wires leading to it. I've always wondered why my A/T Oil temp light doesn't light up...

You should confirm that your A/T Oil temp lamp is not burned out. Otherwise you may get sucked down a rabbit hole thinking it's one thing and not keeping an open mind about other possible problems. My post that you quoted was about all 3 lamps (A/T Oil Temp, Brake, and Oil Level) not lighting up, not just the A/T Oil Temp.

 

[Rusty Cruiser]

You should confirm that your A/T Oil temp lamp is not burned out. Otherwise you may get sucked down a rabbit hole thinking it's one thing and not keeping an open mind about other possible problems. My post that you quoted was about all 3 lamps (A/T Oil Temp, Brake, and Oil Level) not lighting up, not just the A/T Oil Temp.

I ended up removing the NSS after inspecting the wiring connector and finding it to be in good shape. I bench tested the NSS and found it to be really finicky for continuity in several positions. It would not register going into some positions from one direction, it would from the other, etc. I ordered a new one that should be here soon. Pretty sure that is my issue but we will see!

 

[jonheld]

Very interesting! I am chasing down an intermittent no crank issue at the moment that seems to be pointing to the NSS or the wires leading to it. I've always wondered why my A/T Oil temp light doesn't light up...

If the starter solenoid is pulling in, then the starter logic is good and it points to the solenoid contacts/plunger or faulty battery connection.