No spark or power at fuel pump

1997 JEEP CHEROKEE
130,000 MILES • 4.0L • 6 CYL • 4WD • AUTOMATIC
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NWMICHGUY74
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I bought the vehicle listed above non running Sport model. my voltmeter and fuel gauge are dead. it has a brand new fuel pump distributor, coil, crankshaft position sensor and fuel lines. i checked voltage for the fuel pump and found that it didn't have voltage. I also didn't record voltage at the coil. I had no fuel pressure at the fuel rail. I had no check engine light nor did I get a code after cycling the ignition on and off. While checking electrical connections under the hood, I found that there is no power going to fuse 21 at all. I understand that power only goes to fuse 21 for 2 to 3 seconds after turning the key. I tried that and nothing. I also switched out the ignition switch and still nothing. please help i am totally at a loss

xj 4.0
Dec 1, 2019 at 9:18 AM
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SCGRANTURISMO
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Hello,

This could be a problem with your vehicle's battery or battery connections. Can you please take a voltage reading across the battery terminals for me and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
Dec 1, 2019 at 8:34 PM
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NWMICHGUY74
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I did that yesterday 11.9 volts.
Dec 2, 2019 at 4:06 AM
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NWMICHGUY74
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the xj is turning over just fine. it just won't fire
Dec 2, 2019 at 4:11 AM
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SCGRANTURISMO
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Hello,

Okay,in the diagrams down below I have included the wiring diagrams for your vehicle's engine management circuits. If you follow both the fuel pump and the ignition coil circuits, the common component is going to be the Power-train Control Module [PCM] or "computer". Please ensure that all of the electrical connectors the are going to the PCM are connected tightly and that there is no corrosion or unwanted resistance there. Please get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
Dec 2, 2019 at 9:54 PM
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NWMICHGUY74
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I checked all connections and unplugged the grey plugin that goes into the computer and probed the c3 pin hole in the connector and my test light came on. I believe the c3 plug is coming from the ASD relay. correct? does this mean my computer is shot?
Dec 5, 2019 at 5:35 PM
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SCGRANTURISMO
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Hello again,

That is what it is looking like. In the diagrams down below I have included the diagrams for your vehicle's PCM electrical connectors with call outs and the instructions for the removal and installation of the PCM. There are several companies that you can send your PCM in to and they can repair it,if possible, for you. One that I have used before with great success is Module Experts located in Jacksonville Florida. There phone number is 800-486-0922. They are very competent and professional and will inspect your PCM and tell you what is going on with it. Please keep us updated.

Thanks,
Alex
2CarPros

Dec 7, 2019 at 7:40 PM
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NWMICHGUY74
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thank you. but I gave up and took it to the dealer. I'm letting them diagnose it.
Dec 8, 2019 at 10:35 AM
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STRAILER
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Sorry we couldnt help you get it fixed can you please post what the problem was?
Dec 11, 2019 at 10:51 AM
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NWMICHGUY74
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yes when I get it out of the shop. thanks everyone though.
Dec 11, 2019 at 11:13 AM