2008 Chevy Impala LT 3.5L Flex Fuel
No crank, no start. Basic code scanner reads UO100 code only. IP display reads
Starting Disabled,Service Throttle,Engine
Power Reduced. Everything but engine works. Also, fuel pump relay and ECM relay are clicking very rapidly with key in run position. Had battery tested, its fine, cables good, connections good. All fuses in underhood fusebox tested with DMM for continuity and voltage drop, they're all good too.Every " key on" fuse has voltage except the ones involved after the relays, since they wont latch. Swapped relays, nothing. Checked relay sockets, all have battery voltage, where they are supposed to. All grounds good as well. Starting to think ECM or BCM, not sure though? Dont trust any mechanics around where I live. Everyone, including Chevy dealer, are parts changers only. I can change parts until the car finally works too, I just dont have the huge amount of money to go about doing that! If possible, I would like a real mechanic to walk me through trying to diagnose my car knowing I only have a basic scanner, and a nice quality DMM, and the willingness to do what you ask of me. Also, I have a subscription to Mitchell 1 DIY for most wiring diagrams.