In a k 1500 1990 sliverado which color wire is for the reverse lights

Radio wiring

https://www.google.com/search?q=1997+ford+e350+radio+wiring+diagram

Reversing lights

https://www.google.com/search?q=1997+ford+e350+reversing+light+wiring+diagram

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https://www.tundras.com/threads/reverse-light-wire-location-solved-sort-of.14271/

https://www.google.com/search?sxsrf=ALeKk01LrnCOlTtyjWVdv8ZO-E9Opxg8vw:1584032516556&q=Location+and+color+of+reverse+wire+on+a+2008+Toyota+Tundra?&tbm=isch&source=univ&sa=X&ved=2ahUKEwiD2Nj7tJXoAhWxzYUKHUKsDvUQ7Al6BAgJECs

easiest way to check for sure is , with ignition on but engine NOT RUNNING, put into reverse and with a ampmeter check the wires at the rear light cluster, should be easy to find as should be the wire directly behind the reverse light,

There is not just one huge diagram, it is broken dwon into sections, like vehicle lighting, ignition system and so on. I can give you a link to the wiring diagrams and you can try and find what you need. http://bbbind.com/free_tsb.html

open up the rear bulb compartment cover
and note the color wires running into the reverse light bulb holder

a hand full of fuses as you
use a LED test light or voltmeter to find the right wire

and use those color wires as your power /earth for the reverse camera

or you need the rear loom wiring diagram for that 2006 chev

PLEASE UNDERSTAND that if you mess with any of the lighting on this vehicle it could cause the control module for the lighting system to malfunction and go out and this part the last time I replaced one was$970.00.

Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground
Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground
Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground
Find 3 wire connector going to lense in trunk Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground
Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground
brown wire light green wire & black blk is grd moke sure its good, lit grn back up lights,drk Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground
brn tail lights turn parking lights on & with a test light back probe connector no power to brown? ck fuse trace harness to switch wires all good bad switch if you know how to use ohm meter you could use that to ck for shorts on continuity Pin
Wire Color
Circuit No.
Function
A
BRN
9
Parklamp Feed
B
LT GRN
24
Backup Lamp Feed
C
BLK
750
Ground

Really dont need to know color of wire for this system is simple. On the switch (left rear corner on transmission) there are three wires. one wire is power, one allows it to start in park or neutral and the other is for the reverse lights. If I remember correctly the two outer terminals operate the reverse lights. Find the power lead and jump to each of the other two to determine which is for the reverse lights. Likely you will find that the switch is bad and there is no wiring problem. Make sure that reverse lights have good grounds as well.

Would appear to be a wiring problem. Most wiring harnesses connect at the rear of the vehicle. You will need a test light witrh a probe to check up the wire leading to the connector. When you find where the problem is just repair the wire or plug that is not letting the current pass on thru.

Check the wires with the car in reverse and the key turned on, use a meter. On cars the black is usually the ground but you need to check to be sure.