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04 1500 5.7 ASD relay and PCM issues

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Old May 1, 2021 | 02:05 AM
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Angry 04 1500 5.7 ASD relay and PCM issues

Looking for help with a 2004 ram 1500 5.7 electrical system. ASD relay not getting ground signal from PCM. PCM has been replaced with a new one
 
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Old May 1, 2021 | 10:58 AM
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Does the fuel pump prime when you first turn the key on? Do you see power at the coils/injectors for a couple seconds at key on?
 
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Old May 1, 2021 | 11:00 AM
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Originally Posted by HeyYou
Does the fuel pump prime when you first turn the key on? Do you see power at the coils/injectors for a couple seconds at key on?
Nothing activates. Dash turns on, but gauges don't function and nothing primes. But if you jump the ASD relay to supply ground to it then pump primes and injectors clicks and dash activates and will start.
 
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Old May 1, 2021 | 11:02 AM
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Test the wire from the relay, to the PCM, for continuity.
 
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Old May 1, 2021 | 11:07 AM
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Originally Posted by HeyYou
Test the wire from the relay, to the PCM, for continuity.
Done that and it's good as it sees the 12v positive but no ground signal. Computer not getting a soemthig to tell it to switch and sent ground.
 
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Old May 1, 2021 | 11:17 AM
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If the PCM doesn't even want to prime the fuel pump..... that sounds a lot like a pcm failure. Is it showing any codes?
 
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Old May 1, 2021 | 11:19 AM
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Originally Posted by HeyYou
If the PCM doesn't even want to prime the fuel pump..... that sounds a lot like a pcm failure. Is it showing any codes?
Brand new PCM installed. No codes. If I jump the really pin 87 to 30 it will Prime and run. So not sure what signal the computer is not getting
 
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Old May 1, 2021 | 11:23 AM
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30 to 87 is bypassing the relay completely. If you ground the control circuit, does the relay activate?
 
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Old May 1, 2021 | 11:54 AM
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Originally Posted by HeyYou
30 to 87 is bypassing the relay completely. If you ground the control circuit, does the relay activate?
When I apply ground to connector 3 pin 3 at the PCM. Which connected to relay. It will activate.
 
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Old May 1, 2021 | 12:04 PM
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So, for whatever reason, the PCM isn't tripping the relay. Most of the causes of that would set a code..... others, not so much. Have you tried a different key/fob??
 
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