Trailer wiring 2008 Trailblazer SS

Your truck may have had the factory trailer tow package, but that did not come with a wiring connector in that year. There should be a wire harness under the rear of the truck near the center of the bumper with 7 wires of the following colors/characteristics -

Red/Orange - +12V Battery (Thick Wire) From fuse #8 (40A)
Black/Orange - Tail Markers (Thick Wire)
Light Blue - Trailer Brakes (Thick Wire)
Violet/Black - Backup Lights (Thin Wire)
Dark Green/Red - Left Stop/Turn - (Thin Wire)
Brown/Red - Right Stop/Turn - (Thin Wire)
Black - Ground - (Thick Wire)



Under the dash, the brake controller wiring should be -

Red/Orange - +12V Battery (Thick Wire) From fuse #8 (40A)
Black/Orange - Ground - (Thick Wire)
Light Blue - Trailer Brakes (Thick Wire)
White/Tan - Brake Light sense - (Thin Wire)

Hope this helps.

hope this helps

6 pin socket

6 pin plug

7 pin socket

7 pin plug

5 pin socket

5 pin plug

7 pin socket

7 pin plug

7 pin socket

7 pin plug

7 pin socket

7 pin plug

12 pin socket

12 pin plug

small 6 pin round plug & socket

1 tail, clearance - brown

2 left hand turn - yellow

3 right hand turn - green

4 stop - red

5 electric brakes - blue

6 earth - white

small 7 pin round plug & socket

1 left hand turn - yellow

2 reverse - black

3 earth - white

4 right hand turn - green

5 electric brakes - blue

6 stop - red

7 tail, clearance, side markers - brown

round socket

large 5 pin round plug & socket

2 left hand turn - yellow

3 earth - white

5 right hand turn - green

6 stop - red

7 tail, clearance, side markers - brown

large 7 pin round plug & socket

1 left hand turn - yellow

2 reverse - black

3 earth - white

4 right hand turn - green

5 electric brakes - blue

6 stop - red

7 tail, clearance, side markers - brown

7 pin round heavy duty plug & socket

1 earth - white

2 left hand rear , clearance and marker - black

3 left hand turn - yellow

4 stop - red

5 right hand turn - green

6 right hand rear , clearance and marker - brown

7 reverse/auxilary - blue

7 pin flat plug & socket

1 left hand turn - yellow

2 reverse - black

3 earth - white

4 right hand turn - green

5 electric brakes - blue

6 stop - red

7 tail, clearance, side markers - brown

flat socket

12 pin flat plug & socket

1 left hand turn - yellow

2 reverse - black

3 earth - white

4 right hand turn - green

5 electric brakes - blue

6 stop - red

7 tail, clearance, side markers - brown

8 battery supply - orange

9 auxiliaries - pink

10 earth - white

11 rear fog lamp - grey

12 auxiliaries - violet

Hello Carol, The 7 way is for use with a brake controller and/or a trailer that has electric brakes. The 4 way flat is a basic trailer plug connector.
Connect as follows:
Green wire- Connects to the vehicles right turn wire harness & provides brake light and right turn signal on trailer.

Yellow wire- Connects to vehicles left turn wire & powers brake light & Left turn signal on trailer

White wire- Ground

Brown Wire- Tail/ marker/ license plate lights

The Blue, Red & Purple wires on the 7 way will not be used on the adapter, those are for brakes.

I hope this information is helpful.

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Trailer Wiring Diagrams 4 Way Systems

4 way flat molded connectors allow basic hookup for three lighting functions; right turn signal / stop light (green), left turn signal / stop light (yellow), taillight / license / side marker (brown) and a ground (white).

4 way tow vehicle side.
4 way trailer side.
5 Way Systems

Same as 4 way system listed above but adds a extra blue wire for brake signal or auxiliary power. Used on pop up camper trailers or utility / boat trailers.
5 way tow vehicle side.
5 way trailer side.
6 Way System, Rectangle Plug 3/4 inch by 1 inch 6 way rectangle connectors right turn signal (green), left turn signal (yellow), taillight (brown), ground (white). The red and blue wire can be used for brake control or auxiliary. Use on a small motorcycle trailer, snowmobile trailer or utility trailer. Can also be used as custom wiring on trailers with 3 light/wire systems. See "Tow Vehicle Taillight Wiring" below.
6 way tow vehicle side.
6 way trailer side.
6 Way Systems, Round Plug

Round 1 1/4" diameter metal connector allows 1 or 2 additional wiring and lighting functions such as back up lights, auxiliary 12v power or electric brakes. Note: The black (sometimes red) 12v and blue electric brakes wire may need to be reversed to suit the trailer. Check with a test light or VOM. Uses: horse trailer, travel trailers, landscaping trailer, car trailer, etc.

6 way tow vehicle side.
6 way trailer side.
7 Way Systems

Round 2" diameter connector allows additional pin for auxiliary 12 volt power or backup lights. Uses: heavy duty landscaping trailer, car trailer, boat trailers, horse trailer, travel trailer, construction trailer, etc. Check with a test light or VOM.

7 way RV flat blade tow vehicle side.
7 way RV flat blade trailer side.

1. connect the red wire to the stop lamp switch lead on the brake control. Connect the other end of red wire to the stop lamp switch in the vehicle using the splice connector

2. connect the blue wire to the trailer brake lead on the brake control. Route the other end of the blue wire to the trailer connector at the back of the vehicle.

3. connect the white wire to the ground lead on the brake control. Route the other end of the white
wire to the vehicle’s battery. Use the ring connector to connect the white wire to the battery’s negative terminal.

4. connect the black wire to the power lead on the brake control. Route the other end of the black wire to the vehicle’s battery. Use the fuse assembly to connect the black wire to the battery’s positive terminal.

Here you can find information about trailer wires...
- Wiring harnesses & adaptors
- Trailer Wiring Diagram

I hope help you (remember rated this help) Good luck.

a brake controller has 4 wires on it, Black, white, blue,red.

Black is positive battery 12 volts connect to 30 amp circuit breaker to the battery

White goes to good solid ground

red connects to white wire from the brake switch

blue wire connects to 7 way trailer connector at rear of truck. If the truck has trailer package you will find the blue wire and red wires under brake booster taped to the harness you can connect your blue brake control wire to that blue wire. At the rear of the truck the other end of the blue wire will be taped to a harness under the rear of the truck. you will have to now connect the blue wire to the blue input on your 7 way connector

Truck Brake control

Red/Black stripe Black

Blue Blue

Lt. Blue/white stripe Red

White White

Orange Not used

You should be able to access the Prodigy Instructions ie Wiring Diagram At google. Maybe an install video on You Tube. Make sure everything you do is properly fused. Any thing as far as color codes will need to be Prodigy specific. Prodigy may have a 1-800 Tech line. They should be able to E-mail you a PDF file.

Do u have a 4,5,6,or 7 way (wire) system? If it's 4 way it allows basic hookup for 3 lighting functions:
GREEN is right turn signal and stop light, YELLOW is left turn signal and stop light, BROWN is license, and side marker lights, WHITE is ground.

5way is same as above, but adds a BLUE wire for brake signal or aux. power. Its used on pop up campers, utility and boat trailers.

6way (rectangle plug) green=right turn signal, yellow=left turn signal, brown=taillight, white=ground, red and blue can be used for brake control or auxilary. Used on small motorcycle trailers, snowmobile trailers, utility trailers.

6way Round Plug, same as above, but blue is electric brakes, and black (sometimes red,) 12v; note:sometimes red/black need to be reversed w/ blue to suit the trailer.

7way adds an additional pin at plug in for 12volt power or back up lights. Whoa! hope that answers your question w/out confusing u. Let me know if u need more info.