It is my understanding that the shutdown solenoid is energized when the truck is shutoff. Does it stay energized until restarted, or is it on some kind of timer? If continuously energized, is their a signifigant parasitic draw on the battery, or is it some minimal it does not matter.

My reasons for asking are 2.
1. This was my grandfather-in-laws truck, then my father-in-laws. Both drove the truck some, but not regularly. (One a fiver tow'r, the other used it for hunting only). Both had troubles keeping batteries charged or working when the truck sat for a month or so.

2. While poking around under the dash looking for the tachometer hookup leads, I "found" what appeared to be a relay that is hot to the touch. Now this truck had not been run in two days, so to find a hot relay was a bit of a surprise. The dome light had been on for a little while, so it may have been a relay for that, but I am thinking it is for something else.

So, what do the experts think?

BTW, this is for a '91 Ram 250, 4x4, Non-IC

 

The shutoff solenoid is off when the truck is off. There's a spring loaded plunger that is retracted to allow fuel flow to run the truck, cutting the power kills the truck.

That relay is probably the one for the halo light around the ignition key.

 

I didn't even think of that silly light... With that in mind, anyone have any idea what might cause a parasitic load that would kill a battery in 1 month? I know the radio pulls a slight load, but it cannot be much, cerrainly not enough to kill the battery I would not think. I guess the good news is I will drive it more regularly than either of the two previous owners, so the battery should stay charged now.

 

I'm not sure what could be causing it to die. Is the glovebox light going off when the door is shut?

The best way to isolate a current draw is to hook up an ammeter and start pulling fuses until the ammeter drops to zero. Then you at least know what to start looking at.

 

Take off the ground from the battery and place a test light in series. If it lights up then you have something drawing current. Pull fuses and disconnect stuff until you find out what it is.

Modern radios usually draw current to keep the clock and memory going. There's other electronics that probably draw current also. I have seen bad diodes in the alternator draw current enough to run the battery down in a few days but otherwise charge just fine.

If you have a decent ampmeter you can use it instead of the test light to see how much current is being drawn.

There are a lot of little things that are on the line even when the key is off so you'll just have to do it by trial and error. That relay you mentioned is a prime suspect. Can you unplug it?

Edwin

 

The test light method is best for finding shorts. A small draw that kills the battery over a few weeks will not light the light, an ammeter is better for this problem.

 

I will have to get the ammeter out this weekend and start checking things. I did not want to pull the relay, because I have no idea what its purpose is. It looks like a flasher relay, except it is only about the diameter of a dime. Anyone know what this might be? It is under the dash, just to the left of the opening for the fuse panel. I will have to go out and look at it later tonight.

 

It does sound like the relay for the halo ring.

 

another problem, if you start pulling fuses, then your drivers door is probably open which has the dome light on which will show a draw. Also with an under hood light you will show a draw with the hood up.

 

I was assuming he was smart enough to pull those bulbs.

 

Im sure that I never did anything like that