Turn Signal not Working

Okay, yesterday I am updating light sockets, bulbs, and lenses, partially to fix a turn signal.  I fixed the turn signal only to create a problem in another{driver, rear}. The circuit tester on a couple of occasions showed a flashing at the green/yellow striper which I believe is correct.  Is this a wire problem or a relay problem? And, if it is the wire, where and how is the best way to find the circuit fault? I will thank you guys ahead of time for the solution.

Are you sure it's not a green/orange wire?

Here's the diagram and troubleshooting from the '86 EVTM.





You can find all this stuff here on the site under Documentation/Electrical/EVTM/1986 EVTM

If one signal works the flasher relay is functioning.
You should probably try the 4-way hazards to confirm the problem is limited to the left rear and then try the brakes and regular lights on to see if it is a ground or power.

It could be... those wires are as dirty as an older Ford could possibly make them,  and my eyesight aint nothing to brag on anymore.  Oddly enough, the damn thing started working today.  

Everything but that one blinker.  Let me look at the link material that you sent me...Thanks.

The doc. was in detail, thanks. Does the "H" as in LH, RH mean harness? I  bought the truck with the instrument cluster not working so there is no telling what is relatated or causal.  I can do without the cluster but I need my running lights...thank you again.

Just Right Hand, Left Hand...

I'm sorry I screwed up with the second page.
I fixed it as an image instead of only the url now.

There's only one harness down the driver's side rail. Then a connector (C1002) and another chunk of harness that goes across the back, with the near light (C354) and license plate lights branching off before ending at the passenger side (C355) combination lamp.

Edit: it could be as simple as a corroded bulb socket or connector.
I suggested using lights on and brakes to ensure the ground is good because an 1157 uses a common ground for both filaments.

ArdWrknTrk wrote

Are you sure it's not a green/orange wire?

If I am right,  driver's rear flasher wire is supposedly orange, and passenger's side green+orange.

Never understood why, but on Big Bro, rear flashers wires are reversed:  Orange for the passenger side, green/or for driver's.

The page from the 1986 EVTM (above) shows LG/O on the left (drivers) side and O/LB on the right.
Damon's sig shows an '86...

Ford was usually pretty good about keeping colours consistent across years, but at some point switched from hashes (dots) to stripes.

Ok, so Big Bro is correctly wired.
A mistake on the wire diagram (Haynes).
I know that Gary dislike these books, this will give him one more argument.


Their 1984 diagram is so much different than Big Bro, I use the 1980 diagram, it is really close to Big Bro's situation.
But... rear flashers colors are wrongly indicated.