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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: bronson on December 02, 2022, 06:24:51 PM

Title: 84 mci 9 lost all headlights
Post by: bronson on December 02, 2022, 06:24:51 PM
Lost all headlights tonight about 30 min after leaving home. Have power in and out of switch and at breakers in drivers side panel. Could not get screws out of floor piece for dimmer. Was able to jumper wire to lights to get to my destination.  Will be picking up impact driver in am to get to dimmer switch. Hopefully that's where problem resides. Thoughts?
Title: Re: 84 mci 9 lost all headlights
Post by: DoubleEagle on December 02, 2022, 06:50:36 PM
Failing it being the dimmer switch, I would check all connections and grounds. Test any voltage at the switch and find where it trails off. Wiring can be a nightmare, especially if it is buried. I drove MC9's for a Charter outfit, but I never had this problem.
Title: Re: 84 mci 9 lost all headlights
Post by: buswarrior on December 03, 2022, 04:10:44 AM
Pound on the dimmer switch repeatedly, with an assistant watching the lights, if it is daylight.

Happy coaching!
Buswarrior

Title: Re: 84 mci 9 lost all headlights
Post by: luvrbus on December 03, 2022, 04:40:18 AM
Check the head light relays before getting too involved with the dimmer switch
Title: Re: 84 mci 9 lost all headlights
Post by: Tedsoldbus on December 03, 2022, 04:55:25 AM
What bus warrior and luvrbus said. My Prevost went dark. I checked light relays with meter but not smart enough to solve it. Stopped at my mechanic shop. They had me stomp the dimmer button a few times and told me to get out. About 30 minutes later after the electron wizzard tested everything twice, they sent Wilber up to NAPA. New dimmer switch later - no problem since.
But changing it was difficult because of how it was mounted.
$260 later I was in the road to Indiana. I thought it expensive as I drove north, but when you don't have the knowledge like me, you better have money ready. And watching what they had to do, with proper tools, I'd have been half a day just trying to get the old dimmer out.
Hope you get it solved.
Title: Re: 84 mci 9 lost all headlights
Post by: chessie4905 on December 03, 2022, 05:00:03 AM
If you have a compartment under driver's area, check if wiring for dimmer switch is exposed under there. Mine is. Course it is a GMC, but mant things are similar.