I have a 2008 Honda accord and Monday morning the car wouldn't start so we bought a new battery and Put it in. Car started right up. We then noticed the dome light wasn't going off even when switched to the off position. So that's what drained the battery. We then took the fuse out. Well it worked fine all day yesterday but wouldnt start again this morning. Any ideas on what might be wrong? I am stranded at home and going nuts! Thanks!

 

Did you leave the fuse installed overnight this time?

 

We never put the fuse back in

 

If the car will start up using jumper cables, then some electrical component is likely slowly draining your battery overnight.

One way to isolate the circuit(s) is to pull fuses and use the amp setting on your volt meter. There are some threads on this forum covering the specifics.

 

1. Does the front ceiling/maps lights turn on and off properly, even though the ceiling/dome light (the one in the rear?) stays on?
2. After jump starting the car and letting it run a little bit for the battery to charge back up (around 20 minutes), to try to prevent the no start problem again, I would take the bulb out of the dome light. Just use a small screwdriver and carefully pry the plastic cover off to access the bulb. Switching the dome light to "off" should have turn off the light, as the circuit should have been broken, I suspect something may be wrong with the dome light switch. This doesn't rule out something else wrong in the circuit too, such as the MICU or wiring.
3. The circuit includes the door switches on each door, a driver side Multiplex Integrated Control Unit (MICU), a passenger side MICU, and the ceiling light and switch. Before pulling the bulb, I would push each door switch to see if it affects the ceiling lights (open one door at a time and push the switch, they are covered by a black rubber gasket). The lights will stay on; but, will slightly dim when you press the door switch. The MICUs keep the ceiling lights on for a limited time, even if the door switches are depressed.

Edit: Just saw that the fuse was never put back in. Hmmm... a little more complex???