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2000 honda accord ex v6, want crank. I can slam hood down and fan comes on and it cranks but seems like dash lights are dim. Get back in and try again and fan not on, open and slam hood fan come on and it will crank. Relays good egr valve clean. Is it a ground some where or possible bad fuse some where?

Check the ground wire follow it down from the battery to the frame then the block , What does the voltage read with no load then when the battery is under load while trying to start it. You need 12.6 + to start . clean the battery terminals and make sure the clamp is tight . Check the connection at the starter make sure the wires are clean and tight . Hope this helps