License plate lights flashing with left/right signals on.

[94Sierra4x4]

Just got all the wiring to actually work to the rear end of my truck. BUT - my license plate lights are working only when my left or right signal is on. (both license holder lights come on and flash). AND - when I turn my headlights on, the signals begin to flash rapidly. Probably 4-5x as quick as they normally should. :S Electronics are the death of me.. lemme know what you all think!
Thanks.

 

[1997chevydriver]

Bad ground at the back harness. My 94 did the same when the ground to frame was corroded.

 

[jdyates]

Agreed, my whole ass-end went haywire and the ground terminal on the top of the driver-side of the frame, under the bed, was caked with dirt. Unbolted it, wiped it off, wiped the frame off, haven't had the problem since.

 

[awsomeaussies206]

Yup bad ground.... It can do a lot of weird things. I forgot to hook the ground back up when I changed my fender and my horn was turning my high beams on. LOL

 

[94Sierra4x4]

Lol! Thanks for the good info and the couple of laughs there fellas. The ONE thing I didn't check was the ground strap - i don't know why. It was right there staring at me.
Will be pulling that sucker off in the AM and see what it does. Spent an hour with electronic spray/cleaner to clean up the harness and male/female ends. Made them work, but acted weird. She's coming together slowly but surely!

 

[94Sierra4x4]

Cleaned and replaced ground, relocated it aswell, still flashing with signals, and really dim, seems like hardly any power getting to them. Any ideas?!

 

[1997chevydriver]

Cleaned and replaced ground, relocated it aswell, still flashing with signals, and really dim, seems like hardly any power getting to them. Any ideas?!

I have no idea then. I have only heard of a bad ground on the light harness causing that

Sent from my SPH-M820-BST using Tapatalk 2

 

[94Sierra4x4]

Bit of a head scratcher.. Wonder if a wire was spliced to the wrong place, i didn't do the wiring for the trailer harness so maybe somebody made a mistake..

 

[94Sierra4x4]

Courtesy interior lights went out - replaced fused - working again. ASWELL As bringing my cargo light back to life and license plate holder lights no longer flashing.
Weird - but works for me.

 

[badazzbulldog]

i had this issue a week ago it was the right corner marker socket the bulb had melted the inner part of the socket and when i put led bulbs in the running light contact was gounding against the turn contact and made plate lights and dash lights flash when right signal was on