Thank for all the info...and stay away from those tornadoes in your area

 

I am trying to wire my new wiring harness (the black TFI module) and convert it to a gray TFI module harness. In looking at the attached diagram, I started by removing pin 3 from the TFI connector and put in the resistor, I then spliced (soldered) it in with pin 5 from the same TFI connector.

Then I look at pin 3 (which is now empty) and according to the diagram I need to put a "+12v start only" in that spot. In the Chilton manual it shows that wire, pin 3 for a gray TFI module, as going to the starter relay. I have another wiring harness that was originally wired for a gray module that I can't use but I can see where the wires go. If I follow pin 3 from the TFI connector on this harness, it goes to the starter relay. It just doesn't seem to me that information I have is matching up.

My questions are:

For a gray TFI harness, where should pin 3 of the TFI connector go to?

Starter relay or somewhere else?

The wire to the starter relay mentioned in the Chilton manual is the smallest of the 3 wires on the relay, I thought this was input from when the key is turned and not an output signal.

Thanks.

 

Great tfi article. Glad that the OP gpt his question answered.

Thought I'd add my .02 on aftermarket tfis -- I have read that -- at least originally -- many of them did not adjust the dwell as described for the gray oem version. This led to numerous problems, so they got a bad rep. And they deserved it. Probably not the case any more

hj

 

You may have to replace the starter relay with and older starter solenoid as it sounds like you have a starter relay with out the "I" post.
The wire from the key goes to the "S" post.

OR you can splice it in like Ford did on the 199?-1993 Trucks as in the diagram below.

199?-1993 TFI Start wire:


/

 

When I buy the starter relay, it has the "i" post on there and I just cut it off as I only use the "s" post. Would I just get a new one and run pin 3 from the TFI to the "i" post? Right now the "s" post wire from the new black TFI harness I am converting goes to a square, 16 pin connector that mounts on the fender below the brake booster.

 

I do not know why anyone would cut the "I" post off if they were not using it. Most late model ones do not come with the "I" post as it was used to give full power to the Ignition coil during cranking on older engines. It was also used to bypass the fuel relays on older 460 engines during cranking.

I would splice into the wire going to the "S" post and run that wire to the TIF module.