I think your mechanic is not knowledgeable enough to do the job.
There is a fuel pumps relay, I would check that. There is also fuse 13, a 30 amp fuse I would check. The relay gets it's power and ground from a LH Control Unit. If no power and ground to the relay, and the all wires are good, I would suspect the LH Control Unit. Do not use a test light to check for power and ground from the LH Control Unit, use of a test light may damage it. Use a High impedance DVOM.
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