Troubleshooting Tow Ready 4-Pole Powered Trailer Wiring Harness on 2010 GMC Terrain
Question:
I have no trailer lights power at all...bought 2010 terrain with 118494 installed, but doesnt work, trailer tested and works on other vehicle.... changed fuse , cleaned connections..... do lights have to be on, not on auto shift ? thanks
asked by: Ray
Expert Reply:
The Tow Ready 4-Pole Wiring Harness Kit # 118494 is a confirmed fit for your 2010 GMC Terrain that does not have factory tow wiring.
Since you have already changed the harness' fuse and cleaned the contacts on the 4-pole plug I suggest you test the 12V power wire that runs from the battery to the yellow fuse holder. Test the wire to see if power is making it to the fuse holder. If not, then this tell us that the issue is upstream and you should make sure the connection at the battery + terminal is good. Next test the red wire leading into the converter; this is the same 12V power circuit, just downstream of the fuse holder. If power is entering this red wire and going into the controller and you still have no signals at the output, then the unit is fried and needs to be replaced.
This type of powered converter can be damaged if the vehicle was connected to a trailer that had a short in its wiring. The idea is that it is better to have to replace a wiring harness than to deal with more serious internal electrical issues in the vehicle wiring that could occur from a trailer with a short or other issue.
Wiring harnesses do not all have the same current output capacity. It is possible for a harness to be overloaded by the power demand from the trailer lights. The Tow Ready can deliver 2.1-amps to each stop/turn circuit and 5.6-amps to the tail light circuit. You may be able to check the power demand from your trailer's lights. Switching to high-efficiency LED lighting can help reduce power draw from the trailer.
A help article on 4-pole troubleshooting is linked for you.
Product Page this Question was Asked From
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Powered Converter
- Custom Fit
- 4 Flat
- Tekonsha
more information >
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