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First started with my battery light went on, then a few minutes later all the control lights went on, then it did and cannot restart. Added a new Alternator, belt, and checked the battery. How do I know if its my PCM because it looks costly to take to the dealer.
 

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An easy way to determine if the PCM is your issue is to test sensors with a 5 volt reference. You have a multimeter and your wiring diagram right?

The PCM is responsible for sending that 5V current. Key ON, not running. Pick a sensor in your engine bay that has a 5V reference, Multimeter ground probe to ground, positive probe to 5V pin in sensor harness. Should read around 5V. If it doesn't, like way lower, 1.something? PCM is the issue.
 
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