Ignition Trouble

[NicBop03]

So I bought an 88 K5 Blazer about a month ago and it's been a pretty solid truck this far. In the last week it's started doing this thing where when you turn the key the dash lights come on as normal and then when you turn it all the way it clicks and cuts out all electrical power. It won't start until a miracle of messing with wiring and disconnecting and reconnecting the battery a few dozen times.

I already checked the starter, alternator, battery and ignition switch; I also checked the grounds and made sure everything was good. What should I look into now?

 

[Charlie]

 

[73c20jim]

NSS or ignition switch????

 

[JoeR Jr]

If all the electrical power disappears when you hit the starter then I'd bet dollars to donuts you have a bad connection to the battery. Could be the power or ground side, but you've got a voltage drop on one side or the other. Got a test light or multimeter?
Do this:

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Joe

 

[1987 GMC Jimmy]

My Jimmy would do this when I first got it. I couldn’t connect the battery cables tightly so I replaced the worn battery bolts, and then I was able to tighten them down and maintain a good connection.

 

[Cuba]

I would check both ends of the ground cable. Sometimes oxidation impedes good contact on the block or frame. You want to have clean, rust free spots to bolt to. Also check the ends where they bolt to the block & frame. They sometimes have 2 different metals and oxidize within. Copper stranded guts and steel terminal seem to be the biggest culprits, like those found on most aftermarket "pre terminaled" cables.

 

[NicBop03]

Status report: I checked for voltage drop and the NSS and neither were a problem, so I decided to start chasing wires to see if any looked like they had been melted or chewed by a small animal. In my quest for a wire problem I just happened to bump the positive terminal wire on the battery and I heard it arc. Lo and behold that was the only problem. i jiggled the wire a bit and turned the key it fired right up.

So this afternoon I will going to the junkyard to see if I can find an original positive terminal. Since mine has been swapped with top post terminals.

 

[Cuba]

Glad you found your issue.