As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PROP LEVER ACTING LIKE IT WAS HOOKED UP BACKWARDS. PUSHING THE LEVER FORWARD INCREASED RPM, AND VICE VERSA. ADJUSTED LT ENGINE PROPELLER SYNCHROPHASER MAGNETIC PICKUPS IAW KING AIR B200GT AMM 61-23-01. PERFORMED REQUIRED FUNCTIONAL GROUND CHECKS. NO FAULTS NOTED. AIRCRAFT HAS BEEN DETERMINED TO BE IN AN AIRWORTHY CONDITION.