Have a 1989 F150, 4W Drive, with the 6 cylinder engine with 67,000 miles on it. Been sitting for about two years and decided to put it back on the road. I bought a new battery and discovered a short drawing about 3amps.

I did the usual checking by pulling one fuse at a time but could not isolate it. Yesterday I found the start of a solution. At the solenoid on the battery side there are a lot of wires attached on the battery side. There are two heavy gauge yellow wires there and by removing one, the short disappears. Problem is that the wire also disappears into a harness and I can't find the other end. I do have all the shop manuals but I can't figure out how to find what this wire feeds. Help please.

 

Well it goes in one of three places.
1. The EEC Power relay common contact.
2. The fuel pump relay common contact.
3. The Ignition switch.

 

With what Mr. Subford said and what I saw on my truck last night, I'd check your relays. Almost seems as if one is closed when it shouldn't be. I don't remember if there is a fuse for this or not but if there is, it would be in the engine compartment fuse box and not the fuse box in the cab.

 

I pulled both EEC relay and the Fuel Pump Relay. Still shows a draw on my meter. I am trying to figure out how to check the Ignition Switch and where to check it. I have the Ford Factory Manuals Both hard copies and a CD I picked up on EBay for my computer but they are really hard to find things in, for me. I find them confusing to say the least.

I had trouble answering your post yesterday as I was shut out of the forum after changing my email address. I had to register under a new name in order to answer you. Crazy. I was signed in but kept getting message I did nave authority to post or go to certain pages. Maybe I am too old for this sort of thing.

By the way, I want to thank both of you for the very quick response.
Nick

 

Starter solenoid is activated by the ignition switch, the wire from the ignition switch goes through the firewall in a large ~70 pin connector next to the PCM. From there it goes along the driver's side fender, around the front of the radiator and to the SMALL post on the top of the solenoid. Pull that and see if your problem goes away. If not then you might want to replace that, it's cheap

 

On my way out to check it right now and thanks

 

Using a Simpson 260 meter, I get a 1 amp draw from the large yellow wire going to the two above mentioned relays. Removing the wire coming from the ignition switch I get a 2 amp draw.

Maybe I am doing something wrong. I connect the negative side of the meter to the post on the solenoid and the positive lead to the wire itself. Red is plugged into the 5 amp socket on the meter and black on the common socket.

 

Put all that starter stuff back together. Take a picture of your fuses and relays in the engine compartment fuse box and then remove them all, even the diode for the PCM. With everything removed, do you still have a drain? You shouldn't have. The yellow wire goes to that fuse box and supplies power to everything in there. If you still have a drain, maybe remove the fuse box from it's holder and remove the bottom cover to see if anything is fishy in that area. If that's not it, and without being there, I am not sure what else it could be.

 

Not my day. Put it all back together and now it won't start. Going to pack it in for today. Too cold out there for a 77 year old man.

 

He has a 1989 so he does not have the fuse box under the hood.
The Ignition switch supplies power to a lot of things beside the starter solenoid on the fender.






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These are great. Thanks. I have all the manuals except for the red one which is the electrical and vacuum trouble shooting manual. However I do have it on a disk. Think I will print it out. Only 156 pages. I am able to comprehend things better from a hard copy. It's only ink and paper. I reload my own ink and the paper is free. I really don't know how to thank you for all the quick and ready help you have given me. I am assuming you are a former master mechanic and are retired. Am I right?
Nick

 

Yes I have worked as a mechanic and I am retired.
Your are only seven years older than I am.

 

You guys are just kids...just getting the 'feel' of life

 

Something I forgot to mention, is that I must replace the alternator. It is only putting out about 12 volts. I inherited this truck from my uncle about 5 years ago. As you can tell from the low mileage on it he did not use it very much especially towards the end of his life. When I first got it I used it some but it has sat for the last two years.

 

Yellow wires? Ain't those the output leads from the fireball 2G alternator?

If so, get that POS off of there and scrap it (so it won't be rebuilt and turn into somebody else's problem), then bolt on a nice 3G alternator that won't burn your truck down.