Wiring Codes AUX and CHMSL During Brake Controller Install on 2003 Chevrolet Trailblazer
Question:
I purchased a brake controller. On my 2003 trailblazer the wiring codes are called AUX and Chmsl. What do they stand for. The other two wires I can cross reference but I can not figure out these two codes to finish wiring. Thanks
asked by: Dan P
Expert Reply:
The code AUX refers to auxiliary, which is auxiliary power, which should be the Dark Blue wire on your 2003 Chevrolet Trailblazer. This wire will connect to the Dark Blue wire on the brake controller and should be connected to the 7-way as the brake output wire.
The code CHMSL refers to Center High Mounted Stop Light, which is your third brake light circuit. This is the brake signal wire and will be connected to the red wire on the brake controller. This wire should only get signal when the brakes are applied. You can double check this by testing the wire with circuit tester, part # PTW2993.
I made an illustration showing the vehicle wire colors that need to be connected to the brake controller wires. You will want to double check this with a circuit tester, part # PTW2993 as vehicle manufacturers change vehicle wiring colors often.
I have linked a video installation of a brake controller on a 2006 Chevrolet Trailblazer that you may find as a good reference. I have also linked an FAQ Article on brake controllers.
Products Referenced in This Question
Continue Researching
- Shop: Brake Controller
- Shop: Suspension Enhancement
- Shop: Trailer Wiring
- Shop: Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Article: Brake Controller Installation: Starting from Scratch
- Shop: Trailer Hitch
- Shop: Advent Air Low Profile RV AC w/ Air Distribution Box, Start Capacitor, and Heat Strip - 15,000 Btu
- Shop: Curt Trailer Hitch Receiver - Custom Fit - Class V - 2"
- Shop: Towing Mirrors
- Q&A: Longview Custom Towing Mirror # CTM1600 for 2011 GMC Sierra
- Q&A: RC Manufacturing Trailer Tongue Tool Box # 350975 Dimensions
- Search Results: tongue lock
- Search Results: acmhd
- Video: Review of CURT Trailer Wiring - Trailer Connectors - C42JR
- Search Results: 7 way plug
- Shop: Aluminum Liger Trailer Wheel - 15" x 5" Rim - 5 on 4-1/2 - Glossy Black
- Search Results: air suspension compressor kit
- Search Results: air compressor
- Article: How to Measure Your Trailer Wheel Bolt Pattern
- Shop: Redarc Tow-Pro Elite Brake Controller - Dash Knob - 2 Braking Modes - 1 to 3 Axles - Proportional
- Shop: 7- and 4-Pole Trailer Connector Socket w/ Mounting Bracket - Vehicle End
- Shop: Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - GM
- Search Results: redarc
- Q&A: Brake Controller Install Harness Recommendation for 2006 GMC Yukon XL
- Search Results: redact
- Q&A: How Tall is Jounce Spring in Air Lift Air Bag Kit with Jounce Springs
- Q&A: Can Truck with Firestone Ride Rite Kit be Jacked Up by Frame
- Q&A: How To Measure the Bolt Pattern on a 15 Inch Wheel With 5 Lug Bolt Holes
- Q&A: Installing a 7-Way Trailer Connector on a 2008 Chevy Express Van 3500
- Video: Redarc Tow-Pro Elite Trailer Brake Controller Installation - 2016 Chevrolet Silverado 1500