Electrical Oh no not another 88’ turn signal thread!

[Smurfstang88]

Ok so let me start off by saying this is my first post but i am very familiar with forums and such and let my tell you i have searched countless forums on how to fix the turn signals on a foxbody.. So, i am going to start yet another thread woohoo for the same thing AGAIN, because after going through all the steps and the whole process of diagnosing what the problem is, i have yet to find out the issue.. this is what i have done so far to try and figure out my cars issue:
I have replaced the turn signal flasher as soon as i got the car some months ago as that was the easiest.. and yes it does have 12v power going to it.. has 12v power at the fuse panel as well. So i looked over the wiring going to the multifunction switch, and decided it was ok, so big mistake I decided to grab a set of security bits and tear open the switch, and to my surprise it was quite complicated inside and while i couldnt find anything wrong with it, but i also couldnt get it back together (oops).. so I bought a brandspankin new multifunction switch from lmr for a pretty penny (130$) and because it was a 87-89 switch it costs nearly twice the amount as the 90-93 switch ($70, explain that one to me..) anyways I installed it made sure all the wiring for the turnsignal plug was correct via wiring diagrams from forums, and they still dont work... bummer. anyways the hazards work flawlessly so thats not a problem, and when the hazards are on and i flip the turn signal switch it actually makes just the left signal flash no matter which way i flip it.. i dont understand that, and its the same thing the old switch was doing. So to my understanding, after all that they should be working fine but they do not, any help as to why would be helpful, thanks.

 

[Mustang5L5]

View: https://drive.google.com/file/d/1on5czXKmpETzxUggWTGtoUuVkJT2UUxN/view


Perform the component testing on page 121 and 122

Also, test the hazard switch on page 123, as the turn signal power first runs through the hazard switch.

See page 54 for the wiring diagram. Power for the turn signals goes from the fuse block, to the relay, then through the hazard switch and then onto the MFswitch.

 

[Smurfstang88]

Thank you for the manual it seems like it’s useful, but im not sure if im missing something here.. the multifunction switch is new, it definitely works correctly, and to verify that, i did in fact follow the steps just to insure it works properly and it does. I wish i had the manual before I bought a new one.. anyways as for the hazard switch it does work correctly as well. Not sure what else im missing here.

 

[Mustang5L5]

Did you physically test the hazard switch with a multimeter? The hazard lights blinking alone doesn't mean it works.

On page 54, the wiring schematic shows that wire 8 (orange/yellow tracer) works off a toggle in the hazard switch. When the hazards of off, power travels down that wire to the MFS and allows the turn signals to have power. When you turn the hazards on, the toggle to wire 8 is switched off and the turn signals are powered from the hazard switch. Both work together. You really need to test the hazard switch for continuity as per the diagram on page 123 and then test that orange/yellow wire at the MFS when the hazards are off to see if you do have 12V+ there

 

[Smurfstang88]

Thank you for convincing me to take it out and test it haha, i finally pulled out the hazard switch and it actually separated in two pieces where the contacts of the switch meet the plug contacts, and it was already like that when i pulled it apart.. someone had tried to solder the two plastic pieces together and it obviously didnt work. So long story short all i need is the hazard switch to fix it.. and i wish i had found as good information about how the system works before i had bought the mf switch, but oh well.. least i know what the problem is for sure now and how to fix it. Thanks for the help man.

 

[Mustang5L5]

Welcome to stangnet.

 

[Wayne Waldrep]

Excellent thread!