2009 Tahoe Q5i, 4.3 Merc engine. Bought last year, ran flawlessly all summer, stored in heated rodent free storage for winter. Charged battery, checked oil, fresh fuel and took to lake. Tried to start and blew 3 amp breaker under dash a couple times. Checked wiring for shorts, removed starter and bench tested it and solenoid, all seemed fine. Reinstalled starter, careful to hook wiring up correctly and not touching solenoid posts with main battery feed etc. Same issue remained, discovered 50 amp circuit breaker was tripped on engine, reset it and engine now started and runs properly, turned switch off after use and boat continues to run, flipping kill switch on control kills engine, or USUALLY shutting master power toggle off in instrument panel after ignition key switch is off also will shut engine off. Starts correctly with key switch consistently and runs properly, used it several times but not turning off with ignition keyswitch as it did last summer or as it should. Tried disconnecting TKS diode, no change. Also checked 15 amp fuse near carb in wiring harness, it is good, although should not create this issue I am sure. Alternator back feeding possibly? Or any other suggestions, malfunctioning ignition switch? Any suggestions? Thanks.
