mustang430

today i found out what has been draining my battery. today i pulled the fuse inside the car and it was the GEM module fuse. does anyone know how to fix this problem? something is pulling about a quarter of an amp. does anyone know how to fix this problem or what could possibly be running still when the car is off? no lights stay on or anything. also, where is this GEM MODULE located? someone help me!!!

cliffyk

GEM is the Generic Electronic Module, it is located up under the dash on the driver's side and has 2 or 3 (maybe 4) rectangular harness connectors. It controls the warning chimes, courtesy lights, one-touch power window, keyless entry, etc.). It can draw power for up to 30 minutes after the key is turned off, that's why the dark current test procedure for modern cars is so complex.[/align][/align]'Til you've done all this the GEM may not be the problem...[/align][/align]=======================================[/align]From the '03 Factory Shop Manual[/align]
=======================================[/align]Battery—Drain Tests
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) continuous draw.
Check for current drains on the battery in excess of 50 milliamps (0.050 amp) with all the electrical accessories off and the vehicle at rest. Current drains can be tested with the following procedure:
WARNING: Do not attempt this test on a lead-acid battery that has recently been recharged. Explosive gases can cause personal injury.
CAUTION: To prevent damage to the meter, do not crank the engine or operate accessories that draw more than 10A.
NOTE: Many modules draw 10 mA (0.010 amp) or more continuously.
NOTE: Use an in-line ammeter between the battery positive or negative post and its respective cable.
NOTE: Typically, a drain of approximately one amp can be attributed to an engine compartment lamp, glove compartment lamp, or luggage compartment lamp staying on continually. Other component failures or wiring shorts may be located by selectively pulling fuses to pinpoint the location of the current drain. When the current drain is found, the meter reading will fall to an acceptable level. If the drain is still not located after checking all the fuses, it may be due to the generator.
NOTE: To accurately test the drain on a battery, an in-line digital ammeter must be used. Use of a test lamp or voltmeter is not an accurate method due to the number of electronic modules.
[ol][*]Make sure the junction box/fuse panels are accessible without turning on interior and underhood lights. [/ol]
[*]Drive the vehicle at least five minutes and over 48 km/h (30 mph) to turn on and exercise vehicle systems. [/ol]
[*]Allow the vehicle to sit with the key off for at least 40 minutes to allow modules to time out/power down. [/ol]
[*]Connect a fused jumper wire between the negative battery cable and the negative battery post to prevent modules from resetting and to catch capacitive drains. [/ol]
[*]Disconnect the negative battery cable from the post without breaking the connection of the jumper wire. [/ol]
[*]
NOTE: It is very important that continuity is not broken between the battery and the negative battery cable when connecting the meter. If this happens, the entire procedure must be repeated. Connect the tester between the negative battery cable and the post. The meter must be capable of reading milliamps and should have a 10 amp capability. [/ol]
[*]
NOTE: If the meter settings need to be switched or the test leads need to be moved to another jack, the jumper wire must be reinstalled to avoid breaking continuity. Remove the jumper wire. [/ol]
NOTE: Amperage draw will vary from vehicle to vehicle depending on the equipment package. Compare to a comparable vehicle for reference.
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) draw.
[*]If the draw is found to be excessive, pull fuses from the battery/central junction box one at a time and note the current drop. Do not reinstall the fuses until you are finished testing. [/ol]
[*]Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is still excessive. [/ol]
[/align]Battery—Electronic Drains Which Shut Off When the Battery Cable is Disconnected
[ol][*]Repeat the steps of the battery drain testing. [/ol]
[*]Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry lamps to turn off if equipped. [/ol]
[*]Connect the ammeter and read the amperage draw. [/ol]
The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds 50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the battery/central junction box one at a time to locate the problem circuit.
[/align][/align][/align]

mustang430

hey thanks for that info.....here is what me and a buddy figured out so far today. my car was pulling almost a quarter of an amp (.17) and it was like that until i pulled the fuse from under the dash for the GEM. then it went to 0.00. So then i went plug by plug from the GEM module and pulled them out till the draw went away and it didnt go away till i pulled the plug for the power locks/windshiel wipers. But, what dont make since to me is that when i pulled the individual fuses for the locks/wipers the draw was still there???? does that mean the GEM is bad and has a short? I got a price of $315 for a new GEM through his business account but id hate to pay that and it not be it.

cliffyk

I'd let it sit for the 40 minutes Ford says and then check the dark current, if it's still 170 mA (which isn't a whole bunch BTW, a good fully charged battery should be able to supply that for a week and still crank the engine). Ford says it shouldn't be more than 50 mA after 40 minutes.[/align][/align]The reason pulling the wiper/lock/etc fuses didn't change the draw is because the GEM just supplies the control power for the relays and stuff, not the operating juice...[/align]

mustang430

so what do you think is bad??? the GEM or something else??? im nota FORD TECH so should i just take the _ss raping and take it to the local dealership?

cliffyk

You could buy one of the Ford factory manuals on DVD from an eBay vendor ($20 to $30 w/ shipping), and follow the same diagnostic procedures thatdealership mechanics will follow (admittedly aided by experience), or bring it to them and pay 'em whatever they want...[/align][/align]Have you done the Ford recommended dark-current procedure yet? Until you do that you're just shooting in the dark (no pun intended).These things are all computer controlled now, changing parts 'til you got lucky was never a good plan and unfortuantely with these newer beasts it mostly doesn't work unless you get REAL lucky...[/align]

mustang430

my car wasnt ran for all night friday and saturday is when my buddy checked it? does that sound alright or no? after all night of sitting that 170mA was still draining the battery? and we unplugged that one harness and everything went away. that is why i thought it was the one plug? either something in that plug, or in the GEM.

cliffyk

Did you read the part about keeping the jumper wire in place while connecting the ammeter, then removing it to take a reading, then hooking it up again the change meter ranges, etc.? [/align][/align]Each time you break and remake the battery connection you have to wait 40 minutes again--that's why they say to connect a jumper to the batterypost and the connector before breaking the connection. If you don't use the jumper then you have to wait 40 minutes each time you reconnect the battery, either really reconnect it or complete the circuit with the ammeter.[/align][/align]If you break the connection, insert an ammeter, and immediately read the current you will get a high reading because the GEM has awakened and won't go to sleep for 30 minutes (40 to be safe)...[/align]

mustang430

im not too sure how to do all that. im alittle electrical stupid, if you will. maybe ill just have something look at it that knows what they are doing?

jaybird4273

well could be the Ignition Switch not completely turning off, had one do the same thing and replace the switch then the drain went away.