I have a 2003 Honda Accord Coupe EX with the V6. Car just quit starting out of nowhere. All electronics(lights, radio, etc) work with key turned to start, but car wil not start. After replacing battery and doing research,I tried the jump start method supplying 12V from battery terminal to starter terminal with wire and started right up. Any idea what the issue may be?

 

What happens when you try to start it with the key? Does it click? Does the starter spin over?

 

There's a small click near fuse box by left leg and starter makes slight click under hood. Tried different keys, tried starting in Neutral and Drive. Nothing. Jumper wire from battery touching starter terminal, and it fires right up.

 

Your jumper wire direct to starter... which starter terminal???

Small blade-connector terminal:
- This is the "signal" from the ignition switch, so look at that circuit. The ignition switch itself (the electrical switch not the key-cylinder part) has been known to be flaky. If not that, maybe the starter interlocks from the AT or the clutch pedal (depending on your transmission).

Large bolted terminal:
That's the big power cable from the battery. There might be a big fusible link in/near the fusebox? Corroded cable? Corroded clamps at the battery?

 

I jump the starter from my positive terminal on my battery to the smaller terminal on the starter. Cranks up fine everytime. I've since installed a switch between the connection of battery & starter terminals so I do not have to constantly start the car from under the hood. Key does not turn car on by itself. Temporary fix, so I need to find out the issue.

 

You have to trace back "upstream" through the wiring that's supposed to energize that wire which you have bypassed.

What kind of transmission? Each one has it's own interlocks. Automatic has in interlock to prevent operating the starter motor when the transmission is in gear. Manual transmission has an interlock with the clutch pedal.

Then there's the ignition switch itself. Opposite the key cylinder, there's a rotary electrical switch that has been known to get flaky in older Hondas.

Then there's the wires between each of these things; wires can get snagged & broken.