towing trailer can i use a converter from a car

[glenn]

bus is

[H3Jim]

as bus does    )

[NJT5047]

.....MC9?   If you are referring to the tail-light converter, the answer is nope....car converters are 12V...bus is 24V.  
Craig Shepard and Jack Conrad both have built their own 24 to 12V converters.  I wired my Jeep with an additional set of 24V lights.   Works fine, but not ideal.   Very inexpensive solution.  
Good Luck, JR

[glenn]

can you make it work i have 24 v bulb

[NJT5047]

If you add 2, 24V dual filament  bulbs on each side of the toad, all you have to do is sort out the brake, turn, and tailight filaments and wire them directly to your bus brake, turn and taillights.  They are not wired like a boat trailer.  Use one wire for tail, one wire for brakes, and two wires each for LH and RH turn, and a secure ground wire.  Total of 5 leads to the rear of the toad.   RV plug on both the toad and coach so that the pigtail can be removed when not needed. 
These tailights are NOT the toad taillights...they are lights that you must add to the rear of the toad.  DON"T wire the bus into your toad OEM wiring system or lighting system.  That will be bad for the toad electrical system. 
Get some local help with this if you have any doubts....and remember that the bus system is 24V (with exception of the headlights, and that's another complicated issue).

Good Luck, JR 

[Hartley]

If you are going to all that trouble, Just make up your own lightbar with 24 volt bulbs
and a long feeder wire for draping from the back of the toad to the bus.

Or spend the $35 and make up a 24 to 12 volt relay system which will combine the turn and tails
together so any trailer type lights can be used. ( get 25 feet of trailer wire too ! )

I have a set of LED trailer lights wired up with clamps on each light that I move around as needed.

The only extra wire you will need is a 12 volt tap (wire) running to the back of the bus to feed the relays.

Dave.....

It's so complicated you only need to do it One Time.....