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Welcome, I'm Chris (aka Moose).
When it will not crank, does it at least click once or multiple times?
Are the lights you mentioned that are dim when the key is in the run or start position?
This is going to require doing electrical diag when this is occurring using a volt meter. Is that something you can do?
Here is the wire diagram and star relay location.
When the starting issue is occurring you need a helper. We are going to start in the middle of the starting circuit to see where we need to look for this issue. At the starter relay there are 2 large terminals and one small one. Alwasy one large terminal should have 12.6 volts battery voltage. When trying to start the small terminal should have the same voltage and the relay should be closed, sending power out to the starter. All terminals should be powered when trying to start. Let me know these results.
If you're confused on what to do now. You have already been charged the full question value. It's now time to compensate the tech that helped you. The only way I can continue to work here and help customers is by getting rated. If you're not pleased yet or plan not to rate me. Let me know so I can help more, close the post, or opt out. Please let me know if you're pleased with my help.
Yes it could be a bad ground but we have to find out which one, there are ALOT. Were you able to do the test again when it would not crank after an hour. Finding electrical issues sometimes requires finding where the problem is not to narrow down the circuit to find where the problem is.
Is the far left lug the battery all the time lug or the one that gets power when trying to start. I can not tell from the diagram?
Great, so we are making some progress, we know the issue is before the relay because the small terminal was not getting power when trying to start. Just a heads up if needed you can turn the key on and lay a screwdriver over both of those large terminals and start the vehicle if needed. Lets back up to fuse 7 under the hood. On the top of the fuse are test pins. When trying to start you should see battery voltage there. If there is not power there then we need to back up to the ignition switch next.
The TR sensor is on the right side of the transmission viewed from the front of the vehicle. Since the fuse is not powering up when starting the concern is before the fuse, not after it at the TR sensor. Can you do these steps in this file https://dl.dropboxusercontent.com/u/90220402/f53ignition.png
When I was checking the starter relay I checked voltage at the small relay terminal rather than the wire leading to it. Did you remove the wires during this test or was the wire making poor contact at the relay?
I tried your suggestion to start the engine by placing a screw driver over both the large lugs and did not get any cranking. When you crossed both large terminals you bypassed the ignition switch, fuse 7, TR sensor, and relay. You sent battery power to the starter. If both terminals had battery voltage in this test and the starter was not cranking then the starter is bad or has bad connections.
The only way a part of the starting circuit could also cause the stall is if the concern is at the ignition switch. On the starting circuit everything beyond fuse 7 is not used after the vehicle is started. Prior I had you test voltage at fuse 7 when trying to start and you got no voltage there.
When connected to land power there should be no voltage to the starting battery unless someone has wired the charging system to the starting and RV batteries. As long as the starting battery cables and posts has 12.6 volts then its okay and you can move on continuing to see why there is no power in and out of the starter relay.
If you can not get it to crank from the relay by crossing the terminals then you can do the same thing at the starter motor.
Hello again Chris here,
I am contacting you because the post has not been closed out. We have 7 days to get a confirmation that my help assisted you, or the post times out. When a post times out, that means its no longer on my active list (you reply I never know it.) You have already paid the fees to get this question answered, but it appears you're not pleased, or need more help.
Let me help some more. Is there anything else you feel I could offer so you would be pleased with my help. I have the option to call you if that would be better.
I do not believe I can help better over the phone since the diag steps needs you t take time to do the tests.
When the small terminal on the starter relay has low voltage when trying to start with the key. Do you get the exact same voltage at fuse 7 doing the same test?
We can not diagnose the stall issue until we can get it to crank every single time with the key. I work till 3am in TN on here and sleep in late till about noon, then work a couple hours here then go outside and tend to my property and projects, then log back in after dinner.
We have to get fuse 7 powered with the key in the start position. Next test, access the ignition switch on the steering column. Do not unplug it, test the red/light blue wire for battery voltage when trying to start, this wire powers fuse 7 and the starting circuit. If the wire has low voltage check the light green/violet wires there are 2. Do they have low voltage with the key off or while trying to start?
No problem. I think the call would be way to long and a headache for both of us. You need time and both hands to do these tests. Plus a lemonade break in that heat.
Did it start while the key was on when doing that jump and did it start?
Any luck on the tests at the ignition switch?
A bad connection will not cause a vehicle to stall, that circuit is only needed to start the vehicle. Since you get no voltage out of the ignition switch when trying to start but you have voltage into this ignition switch, that means the ignition switch is bad and will need to be replaced.
I am out of ideas. I just do not think I can help you figure this out not in person. Would you like me to opt out and try another tech here.
I have no clue if the next person will even help or if they will read everything. It is for sure electrical related but the results keep changing daily and I feel you are having difficulty following a wire diagram. I am just not seeing any progress which is why another may be able to help more efficient. Opting out now.