MCI Wiring ?

[jmblake]

I have a 1981 MCI9 that I am putting a new CIP dash unit in, And after I removed the old dash and un wraped the wiring harness I discoverd a lot of unused wire's. I was wondering if any of these wire's went to the back for options my bus didn't have. Because I am going to add a tach, jake and who knows what else. The wire's are taged with the #6,15,18A,28,43S50,50P52,53A,59,67,SP. If any one has any info I would really appreciate it, And if any one has a source for a manual that to would be greatly appreciated. Thanks Jason

[Busted Knuckle]

Jason,
Yes in fact in many cases those unused wires are exactly what you suspect! I don't have any knowledge of how many or which ones, or even exactly where you will find them in the rear on an MCI.
But having had wiring issues in the past on several Eagles we found that the manufacture was very helpful in adding "ghost" wires as we called them. Some were for options the bus didn't have, and some were there just in-case!

I believe you are on the right track in looking for a manual especially one with schematics and wiring diagrams! (Good luck reading and following them as some of the ones I have had have been nearly impossible to decipher!)

Sometimes it is best to trace them one step at a time from the dash to the main panel next to the driver, then to the rear panel, or just wrapped up in a junction box or utility chase. Once found you can use meters or such to identify which are what.
I hope this helps and hopefully some of our wiring gurus can chime in and be of more specific help to you.   BK 

[Jriddle]

I bought a tach on EBay. When I got it it was just the Tach Head no sender unit. I went to the bus and stater looking at the generator and was trying to figure out how I would get pulses from the generator to run the Tach. I searched the board for posts on this subject. Then I got out my manual researched the Optional Tach. I started to look for that wiring and in know time had my tach working. I suspect these wires are wired and ready to go as my tach wires were.

John

[NJT5047]

http://www.coachinfo.com/Manuals/Coach/MCI/MCI.html ,  US Coach (Luke), and MCI all sell manuals for your MC9.  
All MC9 manuals are copies and the air system and wiring schemes are sometimes difficult to sort out.
Butch at Servicemotors has some rather prints of MC9 wiring...but, not sure he has an MUI version.  He may have.  MC9 MUI and DDEC chassis wiring may be similar?  Bryce?
Butch can be emailed at <butch @ rvlocks.com>   take out the spaces.    
As BK says, you have blanks in the wiring system.  
If you plan to lose the OTR AC, you'll have another bundle of wiring for whatever.  Unused restroom monitor leads, and interior lighting also frees up wires.  
For a quick and dirty method of ID'ing unused wires between the FJB and RJB, look in the FJB for studs that have only one wire attached to them.  Should be 8 or 10 unused leads.
If you buy a tach, get an alternator tach. There's no driver on the engine. 

JR

[jmblake]

Thanks guys for the info, I would think when they built the bus that they would run extras for options and misfortunes. I will have to investigate a little deeper and trace them down. Thanks Again Jason

[Sojourner]

About locating wire in a jiffy...read the first one of what it is and the second one for low cost bargain.

Wire Tracer / Tone Generator & Probe Kit

OR

Wire Tracer at E-b

I use mine and works evertime...never be without it.

Another great tool to have on hand at all time for owning vehicle that have thousand feet of spaghetti wires.

FWIW

Sojourn for Christ, Gerald