Check the LP fuse on the firewall.
Does the LP run while cranking the engine, that is what the OEM relay does.
There are 10 kinds of people in this world; Those who understand binary and those who don't.
99 CREW LONG SRW C3500 work truck 199k+ mi. orig. motor & trans 4.10, modded engine harness, new oil cooler & lines, all new front end parts and poly bushings, trans poly mount, all new brakes.
96 SUBURBAN K2500 wife's truck 210k+ mi. orig. motor & trans, 3.73...
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