I would say that their sled wiring is defective (probably pulled out of the connector at the crimps). They need to remove the sled from the dash, unscrew the connector from the metalwork and then use a multimeter to test for continuity on all the leads for the tuner connector. It's highly unlikely to be your tuner unless DHS (Yo! Bro's!) has nuked it with something while trying to suss what it was. EMP, anyone?
If his harness is knackered, I have new and reconditioned ones for outright sale, repair, or exchange, available. Get him to mail me on
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