Troubleshooting Curt Custom Wiring Installation on 2021 Mazda CX-30
Updated 08/09/2022 | Published 08/05/2022
Question:
I purchased C86CR Curt 56450 for my 2021 Mazda CX-30 and installed it. But flashing was not correct. When the turn light flashes, the tail light also flashes. Car: Right turn - Trailer: Right light flashes correctly but Left and Tail lights also flash alternately Car: Left turn - Trailer: Left light and Tail light flash together Car: Brake - Trailer: only Right light on Car: Headlight on - Trailer: Left light and Tail light on I checked 4 pin connecter of the car side by an ammeter. This was not a trailer side issue. So, is that installation failure?
asked by: Kay
Expert Reply:
Your 2021 Mazda CX-30 has the brake and tail light functions separated out and the Curt T-Connector # C86CR is designed to combine those circuits since trailers typically combine the turn and brake lights - the running lights should be on their own circuit.
From what you're describing it sounds like you need to replace the Curt wiring kit but I would check the wires going into and out of the black box first. Here is what you'll look for with the wires going into the box vs the wires coming out of the box:
Wires in:
White - Ground
Black - 12V Battery Power
Brown - Running Lights
Yellow - Left Turn
Green - Right Turn
Red - Stop
Wires out:
White - Ground
Brown - Running Lights
Yellow - Left Turn/Stop
Green - Right Turn/Stop
If the lights on your CX-30 are acting just fine then odds are the black box is malfunctioning and you'll want to replace the Curt wiring.
Attached is an installation video for you to check out.
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
more information >
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