Parasitic Battery Drain - 2000 Ford Ranger

[SteveK]

Hello all -

I have a 2000 Ford Ranger with a parasitic battery draw.

I previously did some trouble shooting on it, and isolated it to the circuit that has the GEM module on it, but I cant recall exactly what circuit number this is. This is the same circuit that has the radio on it. In reading and searching, the GEM is suppose to go into "low power mode" after X amount of minutes through a time delay relay. It is not doing this, and draws enough current to drain the battery dead if the vehicle sits for 2-3 weeks (which it does at times). I have tried to find this "time delay relay", but it is either hidden deeply within the vehicle, or part of the GEM itself!

I have mostly been "living with it" and either drive it every once in a while, or put a trickle charger on it.

My question - has anyone every ran into this, and if yes, what did you do to fix it?

.. as a trouble shooting exercise, I am considering pulling the radio and see if this makes any difference.

Thanks!

SteveK

 

[Mechrick]

It's common, although it can be a thru request from something outside the GEM module causing it, such as a lock/unlock switch going bad. Or an interior lamp on somewhere (glovebox, etc.) or your already mentioned radio.

And the trouble shooting is exactly what you suggested, unplugging the possibly offending component to see if the draw goes away.

This is a good candidate for voltage drop testing across the suspect fuse to check if the draw is still there. See:

https://www.autonerdz.com/yabbfiles/Attachments/HowtodoParasiticdraintestacrossfuses.pdf

 

[pjtoledo]

helpful hint.
when dealing with voltages this low, only milli volts, thoroughly clean leads & connections.
make sure connections are very secure/tight.

it doesn't take much to throw the readings off.

 

[SteveK]

It's common, although it can be a thru request from something outside the GEM module causing it, such as a lock/unlock switch going bad. Or an interior lamp on somewhere (glovebox, etc.) or your already mentioned radio.

And the trouble shooting is exactly what you suggested, unplugging the possibly offending component to see if the draw goes away.

This is a good candidate for voltage drop testing across the suspect fuse to check if the draw is still there. See:

https://www.autonerdz.com/yabbfiles/Attachments/HowtodoParasiticdraintestacrossfuses.pdf

Many thanks for the response.

The method you showed in the pdf file is exactly how I isolated the draw to the gem circuit. Once I figured that out, I then put pulled the battery cable, put an amp meter between the battery and the cable. I made sure everything was off, closed the doors, and then watched the meter to see if it would go into a low power mode after about 20 minutes. That is how I lead myself to believe it is not switching into "low power mode".

It has been perhaps over a year since I fiddled with it last. Tomorrow, I am going to pull the schematic out and look at all the "stuff' that is on the cicuit.

QUESTION: By reading your response a few times, you are suggesting that if there is something on the circuit that runs through the GEM, and it is still drawing, it could cause the GEM to not go into "low power mode" ?

Is my understanding correct?

Many thanks!

 

[SteveK]

helpful hint.
when dealing with voltages this low, only milli volts, thoroughly clean leads & connections.
make sure connections are very secure/tight.

it doesn't take much to throw the readings off.

Many thanks for the response. Very well noted!

 

[SteveK]

.. another question.

I cant seem to find my schematics for the truck. I poked around the site here.. but cant seem to find one. Does anyone know where I can geta schematic of this truck (for free or cheap.. )

 

[pjtoledo]

showing my age here, used to find automotive service manuals at public libraries.
stepping away from the free category is of course Ebay
for detailed wiring Chiltons & Haynes usually fall short
there are a couple members here that occasionally will post diagrams.

online search??

 

[SteveK]

showing my age here, used to find automotive service manuals at public libraries.
stepping away from the free category is of course Ebay
for detailed wiring Chiltons & Haynes usually fall short
there are a couple members here that occasionally will post diagrams.

online search??

Hi there PJ!

Many thanks for your response. I have thought about this also.. yes, Chiltons and Haynes are typically very weak - especially for the detail I am looking for!

 

[DeeRanger]

I had a simular problem on my 2001-2.5- 5 speed- 2wd. It was caused by the never used factory alarm system. It had a tiny toggle switch with a blinking red light that was hidden up under the dash just above brake and clutch pedals. It for whatever reason started to not stop blinking, and slowly drained the battery if the truck sat for to long. Just a thought, good luck to you.

 

[SteveK]

Many thanks for all the responses so far!

I have decided to "step back" and get a full schematic of the vehicle from FeeBay so I can definitively determine what is on the offending circuit. I will keep everyone posted for future reference!

SteveK