replacing faulty multiplex?

[stu1873]

I have had a problem with my interior dome light not working when i unlock the Civic for a couple of months now. it works if i put it in the ON position but not on Auto. After checking every fuse under the hood and in the drivers footwell i think it could be the multiplex unit inside the footwell fuse box that is at fault.

Just looking at all of those wires coming out of it looks a very daunting challenge

Has anybody tried this before?

 

[j1thu]

Are you sure its that and not the light unit?

 

[stu1873]

I have checked the dome unit with a multimeter so i am fairly sure its the multiplex.

 

[Shaenei]

Honda can test this unit, it might be worth asking them as it might simply be a faulty light or door switch

 

[jordbalboa]

sounds like a switch to me. The light unit obviously works as it illuminates on demand, just not when the door switch is closed.

 

[stu1873]

I thought about it being the earth on the doorswitch but it doesn't light up when either door opens so sort of ruled that idea out.

 

[jordbalboa]

no idea where the switch is but if you could locate it maybe try bypassing the switch to see if the light comes on.

 

[j1thu]

Have you checked for continuety on the switch, when it's on the door open position? If you have and there is no feed, have you tried to send a feed to see if the light comes on on door open position?

 

[stu1873]

going to test the switch tomorrow. if thats not the problem it looks like a trip to my local Honda dealer to get it checked and probably raped for 70 notes.

 

[Griffin]

should illuminate when drivers and passangers doors are opened and when unlocking and also when pressing the unlock button when already unlocked.

doesnt sound like a door switch problem...

perhaps the switch contacts inside the dome switch are not connecting properly? try sliding the slider back and forth 20 times.

 

[stu1873]

Right, today i replaced my footwell fusebox for a replacement off ebay for £20. It was a bit of a PITA but it did sort out the problem i had with my interior light coming on when i opened the doors or unlocked the car.

My problem now is that my car won't start with the new fusebox!

It appears that the fusebox is coded to the key or imobiliser as the little green light of a key constantly flashes when i turn the ignition on. ****in well ****ed off with it and a trip to the stealers seems now inevitable

 

[Griffin]

Oh bugger

I've never removed one of these but did you replace the whole unit that holds all the fuses and relays with a new unit already housing the fuses and relays?

 

[stu1873]

Yes mate, a complete unit with all fuses and relays intact. only £20 so it's not a great loss. The only thing i can try is change all of the relays from the new one and see if that helps.

After switching back to the buggered one the car fired up first time but now the airbag light is on constantly!

I have just seen this guide on You Tube on how to reset the airbag light on an EP2 so will try that. http://www.youtube.com/watch?v=v1VK5TIQw6I