No Trailer Lights While Hooked Up To 2009 Mercedes-Benz M-350
Updated 07/30/2019 | Published 07/28/2019
Question:
Trailer LED lights not working when we hook up BENZ ML 350, 2009 model. Your advice will be appreciated
asked by: Jai
Expert Reply:
The first thing you are going to want to do is test the trailer wiring harness on the vehicle to make sure you are getting power at the pins for the trailer connector. If you are not then I would need to know what trailer wiring harness you are using in order to troubleshoot further but the ground and power wire/fuse will be a good place to start. I would also like for you to confirm that the trailer wiring harness you are using is compatible with LED lights as not all are. I recommend the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit # 119250KIT.
If all is good on the vehicle's trailer wiring harness, then I recommend you check the grounds for all of the lights on your trailer as well as the main ground for the trailer connector. I also recommend that you check all of your wiring to make sure there are no shorts. If you can provide me with any other info on the vehicle or trailer, I may have additional information for you.
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