Troubleshooting no Power to Trailer Turn Signals

Question:

2001 Chevy 2500 truck drinker lights work on truck but not on trailer ,put test light on green and yellow wire at plug on truck no power at trailer plug in the brown wire did have power.

asked by: Mark K

Expert Reply:

If your trailer turn signals are not working there are a number of different reasons and there are some troubleshooting steps you can take to determine the specific problem.

The first thing to do is take a look at your owner's manual to locate where any trailer fuses or relays and ensure they are all there and in working order. If they are, since you tested the plug on your 2001 Chevy and found no signal at the turn signals, check your connector for corrosion, which can be green or white in color.

A build-up of corrosion can interfere with the signals getting through the connectors so if it is present you will need to either clean the corrosion or replace your truck's 4-way with the Hopkins Endurance 4-Way Flat Trailer Connector Socket # HM48030.

Corrosion is normally the cause but there may also be a short so check your turn signal wiring thoroughly to ensure there are no wires that are crimped, broken or otherwise damaged. An important issue you will want to take a look at are the ground connections, as they can be the cause of numerous lighting problems. You'll want to make sure your grounds are securely attached to bare metal surfaces free of any paint, dirt or corrosion of any kind.

I have added links to a pair of help articles on trailer wiring, including a troubleshooting guide which I highly recommend taking a look at.

expert reply by: Kyle S