Here is what I suspect, your AMP is offline. If you have a scan tool see if you can communicate with it. If you cannot then you either have a power/ground or bus communication issue with it.
Here is all the information you need to run through this with. However, if you have power/ground and the bus is operating properly at the AMP then you will need to replace the AMP. There is no question that the AMP is the issue but just replacing it may not fix the issue which is why you need to verify your proper voltage.
Please review this information and let me know what you response is.
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Thursday, May 2nd, 2019 AT 5:43 PM