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Turn signal problem

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Old Mar 20, 2018 | 09:03 PM
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Turn signal problem

Hey guys, I just bought a 99 f350 Diesel. All lights work except for the turn signals. I replaced the flasher, multi function switch, checked and cleaned every ground wire that I can find, still nothing. When I put my test light on the white/red stripe wire on the flasher block, the turn signals work! What the heck is going on??
 
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Old Mar 20, 2018 | 10:36 PM
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How about the 4 way flasher?
 
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Old Mar 20, 2018 | 10:49 PM
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4 way flashers work. All new bulbs. I found a group of wires going to the light switch that was pretty much melted together. I got a new light switch harness and replaced all of the damaged wires. Surprisingly, all of the other lights still worked even though they were melted together.
 
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Old Mar 20, 2018 | 10:52 PM
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R/W wire hot all the time. W/LB hot in run..Those are the two supplies...
W/R and LB are 4 way controls of some sort.
​​​​​​​Pin 4 of flasher goes to ground. Blk wire.
 
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Old Mar 20, 2018 | 10:59 PM
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Check fuse 23 and fuse 1.

​​​​​​​23 with key on..You know key has to be on right..?
 
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Old Mar 20, 2018 | 11:23 PM
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Yes, key is on. All the fuses are good. When I ground the white/red wire, the turn signals work properly, right and left, however the flasher continues to click on and off....not the lights, but the flasher clicks on and off
 
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Old Mar 21, 2018 | 04:31 AM
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Check those 2 power sources to the flasher with a test light.... Flasher removed!
 
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Old Apr 10, 2018 | 06:55 PM
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Help with turn signals!

Hi guys! So, still haven't figured out the turn signal problem, so I decided to give in and take it to my Diesel mechanic. They had it for 8 days, and couldn't figure it out either. This is so strange. Has anyone heard of this problem before?? I need a wiring expert! Thanks
 
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Old Apr 10, 2018 | 06:59 PM
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Did you do the test with test light like I said? I have a 99 and drawings.
 
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Old Apr 10, 2018 | 07:13 PM
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Not sure what you mean. What wires do you want me to test?
 
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Old Apr 10, 2018 | 09:13 PM
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Post number 4
 
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Old Apr 10, 2018 | 09:31 PM
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So, are you saying that there should be power at that point? What color is the wire? The wiring diagram I have doesn't show much.
 
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Old Apr 10, 2018 | 09:41 PM
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R/W wire hot all the time. W/LB hot in run..Those are the two supplies...

I don't get it. I gave you where to check and colors of the wires. Pull the relay check R/W for hot all the time and the other one with key on. With test light no meter.
 
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Old Apr 11, 2018 | 06:18 AM
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Test the GROUND to the flasher relay module first.
 
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Old Apr 12, 2018 | 06:16 PM
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Ok, so I tested the red/white wire and it does have power all of the time, however the white/blue wire does not have power with key on. I also spliced in a new ground from the battery to the black wire and still nothing. Obviously, the issue is in the white/blue wire. Where does that wire come from?
 
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