Wont Crank no Power to starter

1999 CADILLAC DEVILLE CONCOURS
198,000 MILES • 4.6L • V8 • FWD • AUTOMATIC
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MATTCHEVYGUY
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When i go to start the car the starter does nothing the fuse box clicks but nothing to the starter i tore the intake off and had the starter tested it its fine i replaced the starter relay checked all the grounds and tested all the starter wires on the starter relay plug i jumped from the red wire to the purple starter wire and nothing happened i ran a wire from the battery to that purple starter wire and the starter engaged i tested the 2 yellow wires with key on that i believe to be ignition and pcm and i had 9v on the small yellow and 12v on larger one i have tried about everything i know and i cant figure it out

any help would be appreciated thanks matt
Apr 10, 2014 at 11:13 AM
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RASMATAZ
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Sounds more like its coming from between the ignition switch and starter relay-check for an open circuit-start here
Apr 10, 2014 at 12:43 PM
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MATTCHEVYGUY
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What should i check for?
Apr 10, 2014 at 3:17 PM
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RASMATAZ
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Below is your starter control circuit:

Apr 10, 2014 at 9:36 PM
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MATTCHEVYGUY
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i cannot view the image
Apr 11, 2014 at 11:04 AM
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RASMATAZ
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In cranking position at the key-check for power on the red wire at the starter relay-you should have 12 volts if not check all your battery fuses-there's two of them
Apr 11, 2014 at 1:00 PM
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MATTCHEVYGUY
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all fuses are good but i only have around 2.5 volts
Apr 11, 2014 at 4:38 PM
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RASMATAZ
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Where do you have 2.5 volts at-You sure the battery is okay
Apr 11, 2014 at 5:07 PM
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MATTCHEVYGUY
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battery is charged and fine and im getting between 2.5-3v on the red wire you wanted me the check
Apr 11, 2014 at 5:10 PM
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MATTCHEVYGUY
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if i jump a wire straight from my battery to the purple starter wire it cranks just fine
Apr 11, 2014 at 5:14 PM
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RASMATAZ
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That's not gonna make it-you need more than that

Run a wire from the battery positive post straight to the relay red wire and see what happens-Sounds like the computer is not grounding out the relay to transfer the starter control circuit to the starter motor
Apr 11, 2014 at 5:18 PM
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RASMATAZ
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If you wish you can use a push button
Apr 11, 2014 at 5:20 PM
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MATTCHEVYGUY
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ok ill try that and let you know what happens
Apr 11, 2014 at 5:24 PM
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MATTCHEVYGUY
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ran a new wire and it fired right up thanks for all the help
Apr 13, 2014 at 4:24 PM
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RASMATAZ
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You're welcome
Apr 13, 2014 at 7:18 PM