Starting one time in January, the SUV would have all ACC power but failed in every attempt to crank or turn. Nothing happened whatsoever when the key turned. No dim in the lights, the battery was fine. After about 30 minutes it started right up.
The issue started again this week, occurring twice. Both times while the vehicle had been sitting for more than 4 hours. I’m unsure what the issue is. I took it to Autozone to have them try and diagnose it to no avail.
I saw someone posted this same issue back in December of 2012, however the topic was closed before he had posted the final analysis and the user is no longer active.
It sounds like that other GMC Jimmy you mentioned probably had a bad starter. It’s easy to check if power is reaching the starter solenoid when the engine won’t crank. If there’s power at the solenoid but no cranking, the starter is the problem.
On the positive cable peel back the red cover to expose the battery terminals. If a lot of corrosion is found under the red cover on the terminals replace the positive battery cable assembly.
Starters can easily be intermittent. Normally you would get a click out of the solenoid, but anything the solenoid does can also be intermittent. Battery cable or terminal corrosion can also oddly intermittent.
What jesmed was saying is that it’s really easy to cut the search in half. When you turn the key as 12V signal is supposed to be sent to the starter to tell it to energize. The starter has a big fat wire that is connected straight to the battery and provides the juice for actually turning the engine over to get it going. And it also has a little tiny wire (the “S wire”) which is what activates to solenoid - and that is just a really heavy duty switch for the starter motor. If the S wire doesn’t get 12V, then you know to go backward in the start circuit (e.g. starter relay, neutral safety switch, ignition swtich). If the S wire DOES get the 12V then the problem is PROBABLY the starter.
Anyway, it’s just a very simple diagnostic place to begin. So too is just cleaning and inspecting the cables & terminals.
Excellent comments above. Just to clarify, even when things are working correctly the S terminal usually won’t have 12 volts during cranking. That’s b/c the amount of current to crank the engine is enough it drops the battery voltage. But if you have 10.5 volts or higher on the S terminal during attempted cranking and it doesn’t crank that makes the starter the prime suspect. When making that measurement it is important to measure between the S terminal and the starter case, not the chassis or the battery ground.
I’ll have to wait until daylight to do most of this. Something I failed to mention, I have a remote starter that was installed when I bought the truck.
An intermittent problem relating to the starter is most likely. Of course bad battery connections, and loose wires at the starter could also be possible.
I have seen aftermarket alarm systems cause intermittent starting problems as well.