is the key one that was working in the truck you got the engine from?
have you installed the keypad switch?
do you have access to a scanner?
is the instrument cluster working and is it from the same truck as you have the keys from?
ok , i am not sure if we can make this work but we can give it a try
at the 'PATS' transceiver module, check the rd/lg wire for power in start and run,
check the bk/lb wire for ground,
i recommend that when you do this you load the circuit with a light- a volt meter may lead you astray by showing battery voltage on a circuit which will not carry enough current to do the job!
at the 'RAP' module, check for power to the bk/pk wire and the og/lg wire
check for ground at the bk/lb wire
check the rd/lg wire for battery voltage when the brake pedal is applied
let me know if this helped and if you need more info
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