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Discussion Starter #22
This has really got me stumped. I have no clue what the problem is, I'm probably gonna take it the whole wiring harness and check everything, another question though, if the battery was low, could that cause the fuel pump not to kick on but still late the radio and lights work? I swapped out my old battery for a used "working" battery but maybe it's bad now or something happened
 

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Does the fuel pump use the same wires for the gauge and to make the pump work? If not check those connections. You can by pass the ignition to get the starter to spin with a momentary switch arrangement. had to do that on my XJ at one point. super simple to wire up. Just use a good size fuse in the process.
 

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Guys, this is his 3rd thread on this problem.... in order to understand you need to read all 3 of them...

OP, by starting multiple new threads you are shooting yourself in the foot.... maybe a mod can merge them for you.
 

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Discussion Starter #25
I'm not sure how to get ahold of a moderator, but If a mod see's this, please merge the threads "power, but no crank..." and "no crank, no start" with this thread👍
 

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I am not going to find your other threads.

Have you put a multimeter on your neutral safety switch to verify that it is connected and good?
 

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I'm not sure how to get ahold of a moderator, but If a mod see's this, please merge the threads "power, but no crank..." and "no crank, no start" with this thread👍

Threads merged.

If it happens again just click on the
icon and let us know :thumb:
 

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Discussion Starter #28
So now all the information is here👍, can somebody please help me out here, the newest updates are that I have a new fuel sending unit and a good starter and all the electronics work except for when I turn the key to the run position, the fuel pump doesnt prime. The jeep also doesnt crank when I turn the key to the crank position, I have full 12v going to the starter from the battery.
 

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Discussion Starter #29
If you need a history of previous problems I thought I sorted that could be related to this still, they are in this thread👍.
 

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Discussion Starter #30
So guys, I've got the engine cranking with a remote starter switch and I've got no spark and no fuel being sent... what's wrong?
 

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It sounds like you are not getting power to anything beyond the power control module. Check for power at every fuse and relay in the PCM and advise what you find.
 

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I mean that it cranks with a screw driver. I also just used a test light and when I have a friend crank the jeep while I have a test light down by the starter where the power is sent to it when you crank it, the test light does not light when he cranks the jeep.
I think we can figure this out without shotgunning parts at it. This statement seems like a a good clue and gives a place to test further.

My spot I could check next is the Starting relay at the power distribution center. Find the relay and pull it. There are 4 pins under the relay that you want to check.

There are 2 load side pins. This is the switched side of the relay or the relay will connect these two pins when relay is switched on. One pin is from fuse 4 which is a 40amp (pin 30 on relay). The other pin goes to the starter solenoid down on the starter motor (pin 87).

The 2 control side pins are what enables the switch in the relay. One pin comes from the ignition switch and will have batt + in start (pin 86). The other pin goes to ground (pin 85). This should be grounded if the auto trans is in Park or Neutral Or on a manual, I think it goes straight to ground.

Now how to test this....

Take a test light. Connect clamp to ground or batt neg. Touch each of the four pins. One should light all the time. This is the load side that comes from fuse 4. This is pin 30 on the relay.

One pin should light when key is in start. This is pin 86 (it may be 85). This is power to the coil or control side of the relay.

Now connect test light to battery pos. Touch pin 85. This should light the test light all the time if it's a manual or in Park/Neutral on an auto.

With the test light still on battery pos see if you can find pin 87. This is the pin that goes to the starter solenoid. If the starter solenoid works, it should lightly light the test light. It's a path to ground so should light the test light a little. I am not 100% certain in this but it's worth a try. Also a DVOM should show continuity to ground as an alternative.

Try this and report your results. We can figure this out.
 

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Discussion Starter #34
Can somebody tell me what this connector from under the dash is supposed to connect to? I just was following some wires and saw that this was just hanging here and I cant find where it's supposed to connect to???
 

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Light socket for either the fan switch, or the fog light rocker switch that's supposed to be where your plow light toggle is. Can't remember exactly which without looking at mine.
 
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Discussion Starter #36
Okay thanks, and I have a few others that I dont know what they connect to, I've replaced so much and tested literally everything and i cannot get my jeep to start, it's not getting fuel or spark even though everything is connected correctly and grounded and cleaned... here are some pictures of the connectors that I dont know where they go or what they do.
 

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Discussion Starter #37
So, I just changed my crank position sensor and checked all my electrical connections and I am still not getting any spark or fuel pressure, the pump is getting power to it but not turning on. This is confusing because all the previous forums on this topic say that it's either the computer or the crank position sensor, but I've changed both already... I'm lost and dont know what to test next
 

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If your fuel pump is getting power but not turning on, I would suspect that the fuel pump is bad.

What makes me consider another possible issue is that I understand there's a relay near the power distribution center that controls spark and fuel. I have an older carbureted model so I'm not positive about fuel injected YJs.

Try looking for a post by Got it at last and look in his signature for a link to several manuals. Find the manual that most closely matches your Jeep and search for the engine diagnostic flowchart. Follow the procedures in the flowchart to determine how to discover why your Jeep won't start.

Let us know what you find.

Good Luck, L.M.
 
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