I have known of this problem for a while but have been able to get away with it because I have been using the truck everyday. Now that I am at school, it sits for a couple to two or 3 days at a time. Yesterday, the battery was at about 9 volts when I tried to start the truck. Charging system performing nominally, at about 13.4 volts when at idle and after running for a couple of minutes. Battery tested at about 12.2 volts after the truck was turned off. I put an amp meter inline which only has the ability to measure up to 200ma and the current draw popped the fuse in the meter. Obviously, I have a problem with unattended current draw.

My question is twofold. First, when I reconnected the battery terminal there was a audible relay click. Is this normal? Obviously, I checked to make sure that everything was turned off. Where might this relay be and why would it be closing when power is applied? Again, there are no accessories turned on.

Second; what would the normal current draw be for the truck with nothing turned on and the truck NOT running? Obviously, it has to draw a few ma for the radio and the computer memories but how much is to be expected?

1988 Bronc at the University of Virginia. Wahoo!!

 

to track down where power is being pulled from, hook up a good meter, and pull all the fuses. replace them one by one, closing the door each time, and make sure everything is off. the one that brings it up, is your problem circuit and you can track it from there.

 

I know the drill but am wondering about that relay. I want to get a bit of info before I get down and dirty if possible.

 

theres a few relays, the fuses will tell you which curcuit the relay is on, that why i posted how to find the draw.

 

There is no way that the relay is supposed to be closing when the battery is connected is there?

 

not positive, but i wouldnt think so, I would think that if it was it would kill anything if it sat for a week with a relay on.

 

Its probably the fuel pump relay, they do have the tendancy to stick sometimes. Just check to see if the fuel pump kicks on when you connect the battery, and know that it might not do it every time. No relay should engage on it's own just by connecting the battery.

 

That is the green one yes? Actually I don't think it's that because I hear it click and hear the pump start when I turn the key. Must be something else. I will check this weekend but I need to get an ampmeter first...

 

i had the same problem with my old 1990 F150.....i just unpluged it every time, cuz i couldnt find the problem

 

It wasn't much of a problem, except for autozone, cause they keep giving me new batteries. It is a problem for me now because I live on campus and don't drive the beast so much. I also have to strategically park in case I need a jump. Additionally, it is a personal challenge because I have fixed all of the other little problems recently, including the air conditioning, so only this remains. Well, the door locks too but that it just a matter of buying the new ones as the problem has already been diagnosed.

 

Can anybody confirm that there are three relays in my vehicle? I see three on the electrical diagram: The EEC power relay, the fuel pump relay, and the horn relay. Is this correct? Because, if so, I would surmise that it's the EEC relay click that I am hearing when I connect the battery, since I don't hear the horn nor do I hear the fuel pump come on.

 

I had a 91 F-250 that the EEC power relay stuck closed on me and would drain the battery every 2 days. I replaced the relay and the problem went away.

The normal current draw for this truck with the key off is around 30-40 mA. The radio clock should be the only thing on.

If the EEC relay is stuck closed the fuel pump will not necessarily turn on with the key, if the EEC doesn't try to close the relay right away (because it thinks the key is already on).

A little piece of advice this is a common problem go buy two relays, fuel and EEC if one is bad the other will go soon anyway.

Hope this helps!!

 

I am thinking that I have a misaligned ignition switch. Without diagnosing the problem physically, I surmise that it can only be the EEC relay click that I am hearing. I don't understand how the relay can be bad, since, it is closing when power is applied to the coil, i.e., it's doing what it's supposed to do. Hence, the problem is that power is mistakenly being appllied to the coil. As I remember replacing the switch when I knew very little about my Bronc, I surmise that I made a mistake. The other clue is when I turn the key counter clockwise, it doesn't go to the accessory position, meaning, nothing comes on. I guess the switch could be bad too.

 

Let us know when you replace it if it is the problem.

 

I just had a problem with my ignition. (unrelated to yours) But I knowest that the switch at the bottom of the culoum has sloted mounts. You probubly have to adjust them to get your acsessory back.