I'm not really too sure if my memory is correct about this particular feature. However, I seem to remember seeing an F-150 pick up that was equipped with turn signal illumination bulbs which were built into the front & rear side marker lights.

I know that my 75 F-250 with the standard "Ranger" trim package was NOT equipped with this feature.

If indeed it is a fact, that this was an available feature or possibly even a "factory upgrade" on later model trucks of this type.

Even though my truck was not originally equipped with this type of an upgraded turn signal light package. Would it be at all feasible for me to upgrade my current side marker lighting package to also include the turn signal feature?

At the very least, I'm sure that I'll need to acquire two sets of marker lights that are equipped with the turn signal bulbs & then replace all four of the existing marker lights on my truck.

What I don't know is, how was this feature engineered & implemented? If this change was accomplished via a significant modification within the main wiring harness and /or the connectors. If so, It's probably not going to be worth the amount of time & effort I'd have to put into it!

However, if by chance the Ford design team happened to have had one of those famous "better ideas" Rather than requiring a design modification within the main wire harness. I'm hoping that maybe they decided to keep this feature upgrade strictly within the connector/lamp assembly itself!
If this is the case, it seems to me that an upgrade of this type would be a very easy project to complete!

So, what I need to know is:

1.) Am I correct, did Ford upgrade the side marker lights to also include turn signal illumination?

2.) If so, in what year, model and/or option package was it offered?

3.) How did Ford incorporate this feature into the F-Series trucks

4.) Does this really look to be a feasible type of an upgrade project to consider doing on my truck?

As always, I sincerely appreciate any relevant information, comments and or opinions that anyone has to offer on this particular topic!

Larry Bailey a.k.a. "75 SuperCab"

 

Larry, The '73-'79 Fseries never came from the factory with turn signals within the side marker lights, it might be an interesting project to do though.

 

Im not sure but wouldnt you need a dual contact 194 style bulb? something like the difference between 1156 and 1157 bulbs? Should be simple to wire if the bulb would flash but also burn constantly if the headlights were on.

 

Ford never offered turn signal in marker lights in the US...but in the UK...it was the law at one time..and maybe still is.

Don't know if this holds true for Canada.

 

If you do not understand basic DC electrical circuits do not attempt this!

One way to trick the front side marker lights into acting like turn signals is to "ground" the front side marker bulb to the hot wire that goes to the turn signal filament. The side marker bulb will glow normally when turned ON and will "find a ground" thru the heavy turn signal bulb filament without making the turn signal glow. When the turn signal is activated it drives the "ground" side of the side marker bulb high (applies 12V) effectively turning the side marker bulb OFF. This makes the side marker bulb flash alternately with the turn signal. When the side marker lights are OFF activating the turn signal will turn ON the front side marker bulb thru the "ground" connection and the bulb will flash with the turn signal since the hot side of the front side marker bulb will find another "ground" thru the filaments of the other three side marker bulbs. What makes this work is the low resistance of a cold incandescent bulb filament. Troubleshooting this interconnected maze of wires later will make some mechanic pull their hair out if they have never seen this done b4.

THIS WILL NOT WORK WITH LED TURN SIGNAL OR SIDE MARKER BULBS.

 

T1 - Is this how some cars are wired from the factory? My Grand Wagoneer does this and an old S10 I had did this, too.

 

Thats correct, GM did it for years.

 

[QUOTE=Torque1st]

"One way to trick the front side marker lights into acting like turn signals is to "ground" the front side marker bulb to the hot wire that goes to the turn signal filament."

Since the actual turn signal lights are located so close to each of the side marker lights. It really sounds to me like this would be a relatively simple modification.

The only questions that I would still have left would be:

1.) Does it matter what side of the side marker light is grounded to the turn signal filament?

2.) In order to have all four side marker lights working as turn signals. Does this mean that this "ground" modification would have to be done independantly to each of the four side marker lights or just once to each side of the vehicle?

3.) Does anyone happen to have any information on the color code for the turn signal lights? Which one is the "hot wire"?

I guess it would be just as easy just to use a 12 volt troubleshooting light to find the correct wires. However, just for the sake of providing this information to everyone else, including myself. It would probably be a much better idea to identify the individual wires themselves before anyone attempts to do this modification.

Thanks for all the great info guys!

"75 SuperCab"

 

1- The side normally grounded would be connected to the turn signal.

2-Just do the fronts only!

3-I have no color codes, the wires and connections are obvious to anyone that should attempt this modification. Basic DC circuit analysis skills are required.

 

[QUOTE=Torque1st]

"THIS WILL NOT WORK WITH LED TURN SIGNAL OR SIDE MARKER BULBS."

I have a couple final questions about the information provided. After I posted my previous response I noticed that you had also indicated that this modifcation will not work with side marker bulbs.

This statement would indicate to me that in order to have this modification work properly. I am also apparantly going to need to replace all four of the bulbs that are currently in my side markers.

Q: Is my understanding of this statement correct?

Q: If so, can you tell me what type of replacement bulbs I will need to purchase ?

Thanks again for your assistance,

"75 SuperCab"

 

It will not work with LED side marker bulbs.

It works with standard incandescent bulbs only.

 

If a person was to just use the side marker light as a TS indicator, one would still need a BRIGHTER glowing bulb.
The standard #194 bulb is not near bright enough.

If I was you I would try and adopt/install the new T/S style mirrors instead of fooling with the marker lights.