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Hello everyone. Newbie here. I have a 2006 H3 3.5l with tons of codes. I'm a bit mechanically savy but know 0 to non about electronics. Hummer won't start without jumpers. I've replaced battery and alternator. A few corroded relays and fuses as well. Hummer will stay on until I put it in drive then it shuts off. I have a scanner. I've attached pics of codes. Any help will be greatly appreciated. Thnx a bunch
Does anything happen when you try to start the vehicle prior to jumping (starter engagement, relay-solenoid noises/clicking, etc)? 11-12V running sounds pretty low. Don't know if that has a smart alternator, but put a load on her (headlights+blower+rear defrost) and take another V reading. If it stays the same (or goes lower) something's amiss.
Why was there corrosion on the fuses and relays, you mentioned?