Color code of wiring used for trailer lights.
Posted: Wed Dec 20, 2023 10:42 pm
There have been a few discussions on different forums about the colors of the wiring used for trailer tail lights.
I recently posted on one of the thread's where people were using 7 and 5 wire cables with colors that don't conform to the internal standard color code. The general concensus on the thread was that it didn't matter about following the standard for the colors as the person would know what color he's used for each system. My problem with this was that the next person working on the vehicle or trailer isn't going to have a clue what was color was connect to which system.
Today, I had to sort out a problem with the trailer plug/wiring on a customer's Land Rover Discovery 2. The tail and brake light didn't work and showed open circuit on my tester. I started off by opening up the 7 pin plug on the towbar. There, I found that whoever had installed the towbar had used a 5 core cable, and none of the colors matched the standard layout. The earth wire went from the back of the pin to one of the mount screws and was almost broken off. There was no power to the pins for the tail lights and brakes, so I had to track back up the wires. On the Disco 2, there is a plug behind the right upper tail light for connecting a trailer harness to the standard harness. The installer didn't bother with the plug but used the blade type of connectors to splice into the standard wires. 1 was broken and had old insulation tape around it, and the rest were covered in corrosion, which was obviously causing a high resistance in the connections. The broken one was for the tail lights, and the one for the brake lights had cut the wire completely.
This type of blade connectors cause a lot of damage to vehicle wiring and especially when used on a Land Rover. The wiring used in Land Rover's is a hard type of wire, and the insulation is also a hard plastic. The two metal strips in the connector cut and damage this type of wire.
After speaking to the customer, it was decided that I would cut away the damage wires and splice in the trailer plug wiring directly into the standard loom. I needed to find the Land Rover wiring colors, so I went into the Land Rover Discovery 2 wiring manual. The page in the manual showed the link between the Land Rover wiring and the 7 wires in the trailer cable. I'll attach a photo of the page from the manual. The colors shown in the manual for the trailer wiring are exactly the same as colours shown on the page that I posted previously in the thread I mentioned previously.
I've post in all of the threads that I feel the international color code should be used. In my area there is only one place that sells the correct cable with the colors needed, and that is Venter Trailers Boksburg branch. All the spares shops including the Midas, sell 7 wire cable that have the wrong colors.
What have others found regarding the availability of the correct 7 wire cables in your area?
I recently posted on one of the thread's where people were using 7 and 5 wire cables with colors that don't conform to the internal standard color code. The general concensus on the thread was that it didn't matter about following the standard for the colors as the person would know what color he's used for each system. My problem with this was that the next person working on the vehicle or trailer isn't going to have a clue what was color was connect to which system.
Today, I had to sort out a problem with the trailer plug/wiring on a customer's Land Rover Discovery 2. The tail and brake light didn't work and showed open circuit on my tester. I started off by opening up the 7 pin plug on the towbar. There, I found that whoever had installed the towbar had used a 5 core cable, and none of the colors matched the standard layout. The earth wire went from the back of the pin to one of the mount screws and was almost broken off. There was no power to the pins for the tail lights and brakes, so I had to track back up the wires. On the Disco 2, there is a plug behind the right upper tail light for connecting a trailer harness to the standard harness. The installer didn't bother with the plug but used the blade type of connectors to splice into the standard wires. 1 was broken and had old insulation tape around it, and the rest were covered in corrosion, which was obviously causing a high resistance in the connections. The broken one was for the tail lights, and the one for the brake lights had cut the wire completely.
This type of blade connectors cause a lot of damage to vehicle wiring and especially when used on a Land Rover. The wiring used in Land Rover's is a hard type of wire, and the insulation is also a hard plastic. The two metal strips in the connector cut and damage this type of wire.
After speaking to the customer, it was decided that I would cut away the damage wires and splice in the trailer plug wiring directly into the standard loom. I needed to find the Land Rover wiring colors, so I went into the Land Rover Discovery 2 wiring manual. The page in the manual showed the link between the Land Rover wiring and the 7 wires in the trailer cable. I'll attach a photo of the page from the manual. The colors shown in the manual for the trailer wiring are exactly the same as colours shown on the page that I posted previously in the thread I mentioned previously.
I've post in all of the threads that I feel the international color code should be used. In my area there is only one place that sells the correct cable with the colors needed, and that is Venter Trailers Boksburg branch. All the spares shops including the Midas, sell 7 wire cable that have the wrong colors.
What have others found regarding the availability of the correct 7 wire cables in your area?