Plug It Right
Automotive Electrical Systems

Factory Tail Light Wiring Color Code: Test and Identify Wires

There is no universal factory tail light wiring color code. Colors and pinouts can vary by year, make, model, trim, body style, market, production revision,…

23 August 2026 · 19 min read

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12V Switches Relays And Alternators

How to Choose the Right 12V Dimmer Switch

Compatibility requires matching the lighting architecture, dimming method, connected load, conductors, mounting format and operating environment.

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Trailer Wiring And Connectors

Heavy Duty Trailer Connector: What Must Match

The right interface matches geometry, standard, voltage, circuit functions, conductor limits and component side to the tow vehicle and trailer.

Vehicle Maintenance And Diagnostics

A NOx Sensor Is an Exhaust-System Sensor

It measures nitric oxide and nitrogen dioxide, supplies control feedback and is not interchangeable with a conventional O2 sensor.

Vehicle Maintenance And Diagnostics

Front-End Alignment Symptoms Are Clues, Not Proof

Persistent pull, uneven or rapid tire wear and an off-center steering wheel rank highest. Highway-speed vibration more often points to tire or wheel trouble.

Trailer Hitches Couplers And Towing

Gooseneck Couplers Vary by Fit, Type and Capacity

A 2-5/16-inch ball is common, not universal. The correct component hinges on receiver dimensions, retention hardware, ratings and installation path.

12V Switches Relays And Alternators

How Is a 1-Wire Alternator Wired?

The B+ cable may connect to battery positive or to an electrically equivalent battery-side starter-solenoid or starter junction.

Trailer Brakes And Lighting

7-Way Trailer Wiring With Brakes: What Goes Where?

For the common flat-blade type, identify plug or socket and its viewing side. Match functions instead of colors, then route output and ground to each braked wheel.

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