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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Nineforever on January 19, 2014, 06:14:25 AM
Any one have wirring drawings for headlights on 1981MC9
If your bus has 12V headlights, they might be wired to the schematic in this manual; http://www.busconversion101.com/PDF_Files/MCI%209%20Maint%20Manual%20in%20PDF%20format/MC-9%20-%20Maint%20Manual%20Section%207.pdf (http://www.busconversion101.com/PDF_Files/MCI%209%20Maint%20Manual%20in%20PDF%20format/MC-9%20-%20Maint%20Manual%20Section%207.pdf) MCI switched from 24v headlights to 12v headlights sometime in the 1980's but I don't know when.
If they are 24V headlights I can take a photo of the page in my MC-5C manual, and they are probably pretty similar. One way to tell is if you have the center-tap relay, called the "12V headlamp cutoff relay" located in the AC junction box on the roof of the front luggage bay. If you have that relay your headlights are probably 12 volt. The 12v wiring is not simple to trace, the basic idea is that the headlights are in series from 24 volts so they drop 12 volts each. The "12v headlamp cutoff relay", what I call the center tap relay, is there to supply a 12 volt source to the headlights so that if one burns out the other one will still work. The 24 volt wiring is a lot more straightforward.
Brian
If no one sends you the wiring diagram it will be on page 7-100 of the manual on a 9 they are a PITA if you are missing the diode assembly 7G-12-195 send me a address and I'll mail the page to you if no one else does, this will be for 83 model when MCI finally figured it out
Thanks for the link ... i checked it out the page with headlight wiring is missing chapter 7 page 43 . The problem i have is when i parked the bus last year after changing the engine and transmission head lights were working fine also the lower driving lights in the bumper . Know i go over to the bus in the garage and find out there is no headlights ... just low beam ... no high or driving lights .
Ive did all the simple stuff change light bulbs clean corrision still nothing .
Thanks everyone
Headlamps are in the Exterior Lighting schematic, page 7-44.
Brian
Thank you Brian , that was a big help i was able to rewire and get the headlights and driving lights < fog lights > working the way they schould the conections were curoded and split wires etc . Luvrbus thank you for your assistance and your completly right it was a PITA .