| Author | Message | ||
| edwin b willis (Edwin_b)
Registered Member Username: Edwin_b Post Number: 12 Registered: 3-2005 Posted From: 65.54.97.153 Rating: N/A |
Getting ready for daytona bike week and having trouble with the trailer lights. Is there a trick to hooking to the gmc 4104? thanks in advance edwin b 4104-230 | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 356 Registered: 2-2001 Posted From: 69.77.144.28 Rating: N/A |
Edwin, the 4104 is like a lot of modern cars in that it uses separate brake & turn bulb filaments. Trailers usually use the same bulb filament for both. You will need one of those little converter boxes (that actually have diodes inside) that convert "four bulb" to "two bulb". Most auto stores & any trailer place should have it. There is one other thing that could cause some hassle. All 4104s were originally positive ground. Has yours been converted to negative ground as most have? If you are not sure, check which battery cable goes to the frame. I believe the diodes in the conveter box will be all wrong if you are positive ground. | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 817 Registered: 11-2005 Posted From: 208.54.200.69 Rating: N/A |
My 4104 was probably changed from original because it has four lights that all have tail, turn and stop on each bulb. This means that stop and turn use both filaments in the bulb at the same time for extra brightness. Yours may or may not be wired like this. | ||
| Austin Scott Davis (Zimtok)
Registered Member Username: Zimtok Post Number: 309 Registered: 9-2006 Posted From: 216.37.73.226 Rating: N/A |
Funny thing... The electrical schematics in my 4104 manual don't show the Brake/Turn Signal wiring. I assume my manual has all of the schematics (documents 5500-5513) The parts manual clearly shows that the lower left/right rear lights were "Tail Lamps" and the upper left/right lights were "Brake/Turn Signal Lamps" (I assume each being a single filament bulb)  My bus, like Gus's, now has four duel filament "Tail/Stop/Turn Signal Lamps" I have added back-up lights where the original "Tail Lamps" were located. .  | ||
| Austin Scott Davis (Zimtok)
Registered Member Username: Zimtok Post Number: 310 Registered: 9-2006 Posted From: 216.37.73.226 Rating: N/A |
OOOPS... You asked about trailer lights... When I get around to wiring for a trailer I will be using relays. This will keep undo amp load off the bus's original wiring. My bus is still wired "Positive Ground" but normal filiment bulbs are not affected by the +/- being reversed. LED lights are usually polarity spacific. If you need help in figuring out the relay wiring just ask. . | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 819 Registered: 11-2005 Posted From: 208.54.200.248 Rating: N/A |
Austin, My lights are still just like the original in your top photo but all four are stop/tail/turn. Look on the Signal/Warning wiring diagram for the turn/stop lights. From my weak memory that is what I remember. I'm too lazy to go out to the bus in the cold to look! |