My engine will not crank over - bad starter?

Sounds like you could have a bad starter or something like that. Something could have cooled down etc and now it works.I would still have your battery tested and make sure the battery cables are clean and tight. Also do you have a test light atleast?

Here is the problem with starters most of the time they dont just die they die slow and mess with you with a no start here and a now start there. You will have to see if you have power at the S terminal at the starter where the purple wire goes with the key in the start position when it doesn't start if you do bad starter. That is way to find the problem. If you don't have power there then we have a differnt issue and will have to trace the problem down. Let me know what you find.

Your welcome thats what were here for keep me posted.

Hi,

If I understand, nothing is working now. Do things like the headlamps, horn, radio, or anything at all work? Although the battery is fully charged, are the terminals clean and tight? Take a look through this link:

https://www.2carpros.com/articles/everything-goes-dead-when-engine-is-cranked

Next, I attached a picture of the under hood fuse box. I want you to check what are called the mega fuses. These are heavy duty fuses the power many of the smaller fuses and accessories.

Here are a few links to help when checking the fuses. Do me a favor. In addition to just checking the condition of the fuse, confirm there is power to it.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

_______________________

Please let me know if this helps. Also, let me know if anything is working at this time.

Take care,

Joe

Welcome to the forum. I looked at the starter circuit for 5.3, all the fuses for that circuit appear to be in the underhood fuse box. The yellow wire goes from the ign switch to the crank fuse underhood. I'd check the circuits at the starter relay, underhood fuse box. Voltage for the coil side of relay is hot all the time. Voltage for coil side of relay goes hot with the key in the crank position. Any testing you do at the relay, make sure the tranny is in park or neutral and the e-brake is set.

As far as communicating with the computer, check for voltage at pin 16 of datalink connector, that terminal should be hot all the time, if it isn't hot, check the cigar fuse circuit.

This guide will help

https://www.2carpros.com/articles/starter-not-working-repair

and

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please run down these guides and report back.

Check IGN C fuse 20amp and crank fuse 10amp and Ign fuse A 40amp if okay

Probable causes here could be the park and neutral position switch/ starter relay and ignition switch.

Welcome back:

Have you replaced the ignition switch lock? If you have, are you certain it is properly installed and actually turning the ignition switch (electrical portion) to the start position?

Let me know. Also, if you have replaced the key, was it programmed to recognize the new key?

Joe

Welcome back:

I suspect the immobilizer has it shut down because it doesn't recognize the new key. Try this. Turn the key to the run position (engine off) for about 10 minutes. If the security light is on, it should turn off after that amount of time. If it does, see if it starts.

If the security light is not on, let me know.

If that doesn't do it, you will need specialized tooling to reprogram the system to accept the new key.

Joe

Welcome back:

Okay if it happened before switch replacement and before the starter replacement, the old starter may have blown a fuse, you may have lost ground, or the neutral/park switch may have failed.

First, the first two pics below show fuses that need checked as well as the starter relay. Check those first.

Second, pic 3 shows the neutral/park switch. See if the engine starts in neutral or any other gear.

Third, pic 4 shows the ground for the starter relay. You need to confirm both the ground and the splice (both circled) are good and there is a ground path for the starter relay.

Here are a few links you may find helpful:

https://www.2carpros.com/articles/how-to-check-a-car-fuse
and

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (Below). Let us know what happens and please upload pictures or videos of the problem.

Welcome back:

Did the old starter do the same thing? Let me know. Also, let me know the results of the tests I attached in the prior post.

I will watch for your reply and keep my fingers crossed it's something simple.

Take care,
joe