1988 sierra 1500 backup lights don't work. Need

Question edited for clarity and toss in some CAPS.
Question moved to model category.

These are the best sites.

Simple

2006 Chevrolet Silverado 1500 Stereo Wiring Diagram

https://www.modifiedlife.com > 2006-chevrolet-silvera...
2006 Chevrolet Silverado 1500 Speaker Wiring Guide ; Left Rear Speaker Positive Wire (+), Brown ; Left Rear Speaker Negative Wire (-), Yellow ; Right Rear Speaker ...

Detailed with schematic

GMC Sierra 1500 2006 - SYSTEM WIRING DIAGRAMS

https://portal-diagnostov.com > 2020/04/13 > radio-gm...
Apr 13, 2020 - RADIO - GMC Sierra 1500 2006 - SYSTEM WIRING DIAGRAMS Base Radio Wiring Diagram. Get Access all wiring diagrams car. Mid-Line Radio Wiring ...

2006 GMC SIERRA STEREO PIN OUT WIRING DIAGRAM

https://www.gm-trucks.com > forums > topic > 249614-...
May 4, 2021 - I'm trying to install an aftermarket stereo on a 2006 GMC Sierra ... Can someone please help me out with my truck stereo wiring diagram.
2006 Sierra 1500 SLT Bose stereo wiring diagram
Jul 1, 2021
Wiring Color Code for Radio - GM-Trucks.com
Jan 29, 2002
More results from www.gm-trucks.com

The video here may help.

https://www.google.com/search?q=wire+diagram+for+the+negative+bolted+under+drivers+door+on+a+2010+GMC+Sierra+1500

Grounding points diagram for 2011 Sierra 1500

https://www.silveradosierra.com > ... > Electrical Manuals
Feb 1, 2018 - Looking for a complete list and diagrams of all grounding points for 2011 GMC Sierra SL Crew Cab 4.8. Any help would be very appreciated.

..

Kacy,

GOOGLE 99 GMC Sierra manual (repair, owner, etc) good luck someone probably has put it on-line somewhere.

wiring diagram 2005 gmc sierra 1500 Google Search
This should help.

Hi Steve,
Try search terms "GMC Sierra 1500 wiring diagram". This should yield a good few hits like: Schematic me Free Electronic Schematic Diagram and. http://fuel-saver.org/

which diagram do you need there markies1? can scan it and post it for ya

Do you know what a automotive electrrical wiring diagram is ? How to use a DMM- digital multi-meter ? Pick one system an diagnose an you will probably fix all the syatems . Voltage drop testing . Voltage or ground side problem .
Mastering Voltage Drop Testing with Pete Meier and Jerry Truglia
Free wiring diagrams http://www.bbbind.com/free-tsb Enter vehicle info. year , make , model an engine size. View wiring diagrams an test the circuits.

Hi.

Below you get all the parts breakdown for GMC Sierra 1500, including steering column assembly:

1500 SIERRA

Here diagrams for all 1989 GMC trucks.

If you need to take apart the steering column you will also need wiring. below the color codes and wiring tips:

GMC SIERRA 1988-2005 VEHICLE WIRING

Regards.

Ginko

GMC Silverado also called Sierra, Chevrolet Cheyenne and GMC Sierra Denali (only Mexico)
- Vehicle Wiring
- Wire Diagram GMC
- GM Full-Size Trucks 1988-1998 Repair Information (free register)

I hope helps with this. Good luck (remember rated this help).

Check if there is no power at the bulb socket or check all the fuses, if they are good you have a bad backup light switch, are a broke wire.