I don't see in the wiring diagram that Joe posted where it needs a diode, seems like it should work fine without it, so I imagine you have an issue somewhere else. But if you can't find any other issues and the only time both signals flash is when you plug in the indicator bulb I think the diode will get it done for you.

 

I thank you for the link! Wow, what a dilemma, according to the diagram in the Fordification link the indicator may be a single element bulb with 2 lead wires, 1 for #49 and the other for #50; perhaps some thing similar to the alternator and oil pressure light socket, I will have to test to determine if they will work independently, if would seem so; on the otherhand, is a duel element bulb with duel leads 1 or each turn signal, getting excited I can experiment some more. Anyhow, thanks to U all's help I may be able to sort the issue out today and get the instrument panel back together!!

 

So Dave, back to your original post....

It appears we have similar but different problems with our indicators. We have different dashes, yours being the normal sweep for the CC, and mine being the optional (in a CC) round.

The similarity is in having two lamps flashing when only one should be, and only one when two should be. Yours appears outside the cab, on the park lamps, while mine appears inside the cab in my dash indicators. What do your park lights do when you engage the Emergency flasher? I would not be surprised to learn only one of your lights flash.

All my external signal lights work correctly. But in my dash, when I am turning left, only the left dash indicator blinks, as it should. When turning right, both dash indicators blink. When using the emergency flasher, the emergency light and only the right indicator blinks. Once again, all external lights work properly. I haven't figured this out yet.

So I'm very interested to see what you find...

 

I had similar problems with my turn signal. Turned out to be the signal switch not making contact. Try removing the steering wheel and turning the switch to one side or the other and pushing down on the switch to make contact. If everything comes to life you have a bad switch. Took me a while to figure this out because my column harness and switch were new.

 

Yes, all the instrument panel bulbs are single element, and are grounded to the instrument panel. So for the turn indicator, it just needs a 12 volt supply from either wire #49 OR wire # 50, depending on which connection is made in the turn signal switch. With 12 volts on either wire, the bulb will light.

 

I'm trying to figure out how the switch could be the problem... and I'm not there yet. But thanks for the advice.

 

Jolly Rodger, On mine the pivot point was sloppy and wouldn't allow good contact. My fix was to cut off the retaining head and drill and tap it so I could use a screw and washer to hold it tight (I had to file down the height some). 3yrs now and no problem.

 

Cut wires from both connectors at the column and used spade type connectors to attach the 5 wires, not a particular fan of 'heat shrink' connectors but found works well in joining wires in a confine space. I ended up using an alternator socket with 2 leads and does not appear to be grounded at the instrument panel, intend purchasing a new replacement. I ended up soldering #49 to one of the indicator leads and the other lead soldered to #50, My no means do I suggest the set-up is correct but so far the turn signal circuit is working as it should. I also added a ground strap wire, in the past I found adding a ground wire to a CC panel tends to eliminate some instrument gauge jitters ? I am now in the process of using non-adhesive harness wrap to secure the wires hopefully once complete all is still well.

Again, thanks to all for their input, the Fortification diagram kinda got me back on track?

 

So what do you think fixed the problem? You had only one front turn signal but it was flashing for both left and right. Was there an open or shorted wire going to it within the connector?

 

Not an authority on automotive electrical circuits, mostly a matter of trial and error. Noticed the Fordification link appears to show the CC directional indicator lamp is not grounded with a single element bulb 2 leads, which was different from how I ran the circuit? I am currently using a faulty spare oil pressure socket as a direction indicator lamp until I can replace with something similar or same. I also removed the male pins from the 6 pin connectors and felt there were a couple male and female pins that were questionable so I cut both out and joined them using spade type connectors. I also added a ground strap from the instrument panel and ran it to the brake assembly bracket found it tends to settle gauge jitters?

The directional lamp socket I installed is questionable so until I locate a replacement only going to secure the instrument panel with a couple screws. As yet not convince problem solve, since I do not have a clue when it comes to automotive circuitry electrical gremlins can haunt me?

Thank you for the input!!

 

Okay, maybe this will help you understand the way the CC dash indicator works. Any bulb needs both power (12 volts) and a ground to light. For the CC bulb as shown in the Fordification diagram, the wires for both left and right turn signal are attached. If the left turn is selected, one of those wires, either 49 or 50 supplies 12 volts via the flasher. The light blinks because it has both 12 volts and a ground through the socket and instrument panel. If the right turn is selected, the other wire, either 49 or 50 supplies 12 volts via the flasher and the light blinks because it has both 12 volts and a ground through the socket and instrument panel. The bulb socket must be grounded all the time through the instrument panel. All of the bulb sockets are grounded this way. Notice in the diagram all the other bulbs have only 1 wire going to them... to provide 12 volts.

Does that make sense?

 

It does make sense, I thank you for the clarification!

 

Dave, I had to ground each and every light socket to get my lights to work proper

 

Clarification on the single dash indicator turn signal system used by various manufacturers.
First, the socket must have two wires coming from it, one to each terminal on the bulb, neither one is grounded to the dash panel, AND THE SOCKET MUST BE PLASTIC!! This is critical.
When one of those two wires is given power, and the other grounded, the bulb illuminates, as would any bulb circuit.
The secret is this: the dash indicator bulb grounds through the OTHER turn signal bulb, always the front bulbs.
The reason this works is that the indicator bulb has a filament that needs less power to illuminate, so it doesn't cause the front turn signal bulb to illuminate.
So, for wiring this system, the indicator bulb has one lead to the left front turn power lead, the other indicator lead goes to the right front turn power lead. There is NO ground to chassis at all (critical!!).

The beauty of this system is that you can determine which turn signal bulb is out by watching the dash indicator.
Fast flash - the rear on the side you are turning to, is out.
No flash, one side - the front indicator on the opposite side, is out.

Hope this clears things up.

Probably doesn't.

Cosmo

 

my wiring is different. I was just throwing an option out there. You clearly know much more than I.