Put two new headlights in and turned on the ignition switch with them on and they popped in about a second. What could possibly be happening that would cause this? The engine was not running so it's not the voltage regulator. Vanner? Water in one of the lights? Installed the fans, troubleshooting the jake brakes, headlights popping...... GRRRRRRRR! Have I mentioned how much I hate all things electrical?
I'm working myself like a dog for a vacation. That makes no sense to me.
Pissed and discouraged.
Rick
12V headlamps wired into early MC9's were a screwy set up (the 8's ran 24V bulbs). You have a common problem, had it myself on an 81 9. MCI published a bulletin on the correct fix and a wiring diagram. Get it from MCI, Caylor or JD at C&J Bus Repair in Minneapolis. HTH
Hey Boomer, is it this? http://www.mcicoach.com/service-support/serinfo/assets/1930.pdf (http://www.mcicoach.com/service-support/serinfo/assets/1930.pdf)
And as a side note, high five MCI for posting a document dated May 21, 1980 online in a commonly readable format, and making it free to access.
http://www.mcicoach.com/service-support/serinfo/serinfo07G.htm (http://www.mcicoach.com/service-support/serinfo/serinfo07G.htm)
I had so many problems with the setup on our 8 I finally tossed in the towel and added a group 24 battery and a 12 volt 1 wire alternator just for the head lights it was never a problem after that.
I believe it is Jack Conrad that run his headlights on his 8 off the 12v house system
Thanks for posting that Chessie. That be the one. He needs to rewire so that 24V is not being applied and toasting both lamps.
Hey all,
I appreciate the input but I don't think it's a wiring issue. These lights have worked great for the 9 years we've owned the bus so I doubt it's an actual "how it's wired" issue. A short? Maybe?
My guess is that my bus was struck by lightning at the cabin. The inverter and lights worked great and now they are both acting up. The inverter was actually fried and needed to be replaced. I'm thinking that I'm gonna go check the voltage in my batteries and I bet I'll see issues with different voltages in the batteries. After speaking with JD at C&J he said that the drivers side lights are wired differently than the passenger side (which are the ones that keep blowing) and that the lights on the drivers side and the passenger side are actually wired separately to the two individual start batteries. I bet it will be the vanner. Because I haven't spent enough money already getting ready for this trip...lol.
I may try and claim this on my insurance policy because if it was from lightning it should be covered.
Fried physical light switch or relay? Perhaps creating conditions like a direct short? HB
If you lose the ground in that system it will fry those lights left and right!
;D BK :D
(it will crate symptoms like a direct short by way of sending too much voltage to one side and none to the other BTDT!)
My 102C3 has 12 volt head lights and 24 volt running lights. When I put in the HID lights found that the right side light had a normal ground and pos. The left side changes from pos. to neg one each wire when you go from low to high lights.
The HID will not work like that, but the old lights didn't care. The HID only use less than half the amps so I wired both from the right side. That is a mess the way MCI wired the lights.
Jack
BK, any idea where they ground the headlights?
Not exactly sure off the top of my head, but seems to me they just go a short distance an ground them wherever they can.
;D BK ;D
Rickb mine was grounded in the tire compartment. pas side only. on the drivers side under the floorboard there is a terminal strip and two diodes.i would start there.and cheak the terminals diodes and the wireing that goes acrose. then i would cheak the dimmer switch and wireing.sounds like you got a short to ground. not a bad ground.but it never hurts to look at grounds.have you looked at the two relays? and the wireing that goes to them. ???
I found the wiring in the spare tire compartment. Most of it's rusty and corroded. I'll see if a wire wheel and a wire brush can bring things back to normal and I'll look for obvious exposed wire etc. If that's not it I'm taking it in. Been working on this thing for two weeks and I'm tired.
Have you per chance installed or reinstalled batteries on your coach before this started happening??If so check your battery hook ups.It sounds like you are putting 24v on to your head lite's!! Remember all your lites except your head lites are 24V if your coach is like mine.
Big Red... well, when you're right, you're right. That's exactly what happened.
RB
Missed a few posts :)
My fault for using IE
LOL I read where he and Gumpy solved that little problem last week ;D