Tail Light help please I leave in the am

[BrwBier]

This is "TYPICAL" of trailer wiring using the "common" 4 wire flat connector....

The ground may either connect to trailer chassis and if lights are designed to ground through mounting/chassis you are probably good. IF lights are designed to ground through mounting and mounted in wood or fiberglass you will have to hard wire a ground from connector to lights...

As a side note I always ground bond the ground connection to trailer chassis even if lights are mounted in wood or fiberglass.



Note ground from lamp to chassis (tiny black lines)...

Dale

I repeat NEVER ground trailer lights to the frame (unless you are looking forward to problems). They will work for a little while, and in some cases, where a trailer is never driven in rain and always stored inside, they may work forever. But why would you want to build in a problem? I have been a dealership mechanic for more than twenty years and grounding problems are a major part of electrical work. Each light needs its own ground wire, save yourself the headache
Brwbier

[madjack]

..........grounding problems are a major part of electrical work. Each light needs its own ground wire, save yourself the headache
Brwbier

I agree totally...grounding problems, account for about 90+% of trailer lighting problems...in the case of bolted trailers, this is especially true...each frame member in a bolted trailer is grounded to the others thru bolts onna painted surface...not exactly the best way to go...use a grounding block for the best grounds or run a ground to each seperate frame member of that bolted trailer...
madjack

[Dale M.]

I repeat NEVER ground trailer lights to the frame (unless you are looking forward to problems). They will work for a little while, and in some cases, where a trailer is never driven in rain and always stored inside, they may work forever. But why would you want to build in a problem? I have been a dealership mechanic for more than twenty years and grounding problems are a major part of electrical work. Each light needs its own ground wire, save yourself the headache
Brwbier

The irony of this is almost all trailer manufacturers and car/truck/bus/motor home manufacturers use the "chassis" ground system... If you chassis is not capable of being a proper ground conductor, it is probably not a good chassis to even put on the road... Quality workmanship when doing wiring will ensure either type of ground system works properly not the style/concept of grounding system you use...

IF you have chassis ground problems, be sure to clean chassis connect points to clean bring metal and apply a silicone dielectric grease to connection to prevent corrosion...

http://www.pplmotorhomes.com/parts/rv-l ... grease.htm

I always make crimp connections and ground connections and install bulbs with a similar product. It prevent oxygen from getting into connection and causing oxidation...

Chassis grounding always worked for me (except for bolt together chassis) ... This is from almost 40 years experience if telecommunications (systems grounding) and accumulated automotive experience....

Dale

[BrwBier]

Please point out any auto manufactures that use the chassis for a ground for anything except engine starting, I want to stay away from them.
Brwbier

[Dale M.]

Please point out any auto manufactures that use the chassis for a ground for anything except engine starting, I want to stay away from them.
Brwbier

Just check out any automotive lighting on cars/trucks/busses manufactured in the last 60 years.....

Only since electronic engine controls (computers) came into being has the auto industry started using "return" (ground) wiring, and in most cases not for lighting unless fixture is made of plastic or mounted in "plastic" body... They (the manufacturers) are not going to put full ground wiring in any vehicle they do not have to because each extra inch of wire has a cost factor. Besides you have this huge ground conductor already sitting on the wheels, its called the chassis and body.

Dale

[BrwBier]

Belive what you want.

[Dale M.]

Bet you believe the electron flow in a DC circuit is from positive to negative too....

Dale