Question about battery saver and amp draw

[Lemondrop]

My wifes explorer 5.0 (1996) is having a problem with waking up to a dead battery . The battery is 1.5 years old and I had the battery checked and it is fine . You can run the truck all day and it starts fine . Just after sitting 10 to 12 hours it will not start without a jump .
I hooked my amp meter up and started checking . I have a half amp draw with nothing on . I figured the PCM would need some amps to keep alive and also the radio but the .5 amp is a tad much methinks . I started pulling relays on the engine relay panel and then the fuses behind it . WHen I reached the "Battery Saver" relay It dropped to .07 amps which is more in line with keeping memory . I was going to pull the battery saver relay but I can't find it off the owners manual's description ...... it shows it in the lower middle of the windshield
I tried the headlights with the fuse (30 amp fuse) and the headlight would come on but no park lights so obviously I can't leave this fuse out to prevent a dead battery . The interior lights are not staying on and Ive verified this by monitoring the amp meter and watching the lights/amps go up/down/on/off .
Anybody got a clue ? Im hoping the friggin GEM is not a dead duck ...... I guess I could hook my Diagtek up and do a GEM test .
Shoot me some ideas if you guys got any .

 

[Lemondrop]

Ok,
GEM test rode fine . I selected the parameters and viewed them . Only one I saw that was strange was the "Heated Backilight Driver" goes short to ground when the ignition is off but by the way it does this I think it is designed to . It all functions normal with key on so I think it may be normal function .
Ive pulled the fuse out and have my voltmeter on it , when you remove the fuse it will gain .02 volts . When you put the fuse back it starts dropping .01 volts sloooooooooowly as you sit there . I mean real slow .
Any ideas ?

 

[BradE.]

Sorry if this is OT, how do your like your DiagTek?

I'm seriously thinking of buying one.

 

[Lemondrop]

Like it pretty good , has some quirks (errors out when you try to read some codes ,etc.) but over all it works good . I had a problem with it reading my ABS on my 95 and Diagtek fixed it and sent me a patch that made it work .
If I wasnt so far behind on newer electronics for cars Id be in heaven . If this sucker was a Caterpillar engine Id be loving it right now

 

[canada74]

check the volt regulator

 

[Lemondrop]

Ehh what volt regulator ? The one in the alternator ?

 

[Kadarom Douhrek]

The "battery saver" turns off all interior and cargo lights 40 minutes after the ignition is turned off and the last door is opened/closed.

So, turn the truck off and check the draw.
Then check it 40+ minutes later and see if it has dropped.

My 94 service manual says the current drain should be less than 0.05 amps.
I highly doubt newer models would be much different as they use the same batteries.
But 0.07 might be alright.


And the voltage regulator shouldn't be a problem since the alternator is obviously working.

 

[Lemondrop]

Ive got a CD manual I got off fleabay and Ive been reading . Seems my half a amp is too much and it is as you stated (supposed to be .05 ) .
Im not worried about the extra .02
It's the extra .48
Right now Im holding a steady 12.64 volts with the fuse out . Im going to leave it like it is until morning and try to fire the truck . If it starts without dragging down (slow cranking from about dead battery) or just does not start then I will consider I have found the culprit .
Though I have only eliminated all but 1 circuits
The circuit has multiple paths but most flow through the Battery Saver relay . My next thing I will try is swapping the BS relay . If the BS relay is sticking and there is a draw then the battery will be dead . If the GEM module is holding the Battery Saver relay on them Ive got a craptastic GEM (no surprise there) . I wish I didnt have to work tomorrow . These things always start Sunday afternoon .

 

[Opera House]

And if you don't want to be saved?

Battery saver draining battery!!!!! If this GEM output was bad, you could just jumper the relay contacts and be careful with the lights. However, this relay draws less than 0.2A. I have a continuious load on my battery of more than that from add on accessories and I never have any problem. This circuit controls all those lights that you could leave on by accident, like the hood light. So this sounds like the relay still on for the required time period and one light is still on. Think you are following a red herring because for this drain to happen there would have to be two independent failures.

A half amp is not enough to drain the battery overnight. Thr battery is typically over 60 amp hours. If you still have 6 amp hours left, you can start the vehicle in good weather. Try measuring current from the battery. I suspect an alternator drain.

 

[Lemondrop]

I left the fuse out for the battery saver and this AM when I tried the truck it started but barely . It was turning pretty slow and then fired up so apparently I have another problem . Im thinking the alternator might be wacking the battery , it's charging fine and holds a load but I think it's draining across the field . Perhaps the voltage regulator is stuck on and keeping it going or something .... Im not sure why my load dropped to .07 amp from .48 (or so) with the fuse for the battery saver circuit out .
My wife is taking it to a auto parts store to have the alternator tested right now . I doubt they will find anything as I ran the "factory" load tests on it when this started and it passed .... I never ran the "field drain" test so it's next up . If all else fails Ill disconnect the entire battery tonight and then reconnect it in the morning and see if it starts . The guy told me it was ok but Im wondering if it's internally shorted and slowly taking the battery down .
We have had the truck back for about 2 weeks now , my wife smashed the front end up on the side of a F-150 .... Im hoping the body shop did not fry something when they welded the new radiator core support on . The wiring and all did not take a hit just had a small bend in the core support that would have been noticed after it was pulled out so we wanted a new one installed .
I'm pretty sure the accident and this problem are unrelated since it was fine for almost 2 weeks after we have had it back but you never know .
Im sure as with everything of mine it's gonna be a PITA .

 

[BIG COUNTRY]

I'D go with canada on this one...check your voltage regulator...or perhaps your alternator has gone bad...
if you have a multimeter, put the two leads on the battery 1 positive and 1 negative...normal volts should read between 12 - 12.40 volts...start your X up, and the volts will normally go up to 12.75 - 13.50 volts, if it does not go up, then your charging system is bad meaning your alternator...good luck
or perhaps your batter saver relay has gone bad...
the relay is in your relay module box...located on the driver's side (left handed vehicles) by the gas pedal, look behind the dash up top right above the floor heater/ac vacuum valve motor....there is two screws, the top one is a PITA!!!
in there are 7 relays...one big one, and 6 small ones.
1. accessory relay....(big relay)
2. battery saver relay
3. parking lamp relay
4. head lamp relay
5. dimmer relay
6. one touch down relay (driver's side auto window)
7. cant think of this one...i forgot it...

 

[Lemondrop]

She stopped by Discount Auto parts and had it checked . The tester there said her battery was bad . I guess the fun starts .......
The battery is a walmart battery and Walmart tested it and said it was good . Im disconnecting the battery tonight and re-connecting it tomorrow and if it won't crank ... end of story .

 

[Opera House]

Walmart should be OK with it

I tried to return a Champion battery to Walmart. They told me they never sold Champion. "But, it says Walmart right on the battery label." All you have to do is find omeone half way intelegent!!!!! I could believe a battery after an accident. The regulator inside the alternator is connected to the battery all the time so a fault could cause the field to be on all night. This has a seperate 15A fuse. The regulator turns on when voltage is sensed on the wire for the idiot light.

 

[Lemondrop]

She took it to Walmart and they tested everything on the truck (Charging,starting,battery) and said it was all OK . She griped to them about Discount Auto finding a bad battery so they just replaced the battery . I guess tonight will tell the tale with the new battery . With the other battery it started right up this AM (I disconnected it last night) but that does not really tell me if the battery had anough capacity to run the small load overnight and allow for a engine start .
Im going out to check the drain on the alternator just incase .
Hopefully this saga ends tonight

 

[Lemondrop]

Walmart slapped a new battery in it and this morning it started like a champ . I guess Ill know for sure in the next few days if it does it again .
I wish I had invested in a battery load tester years ago , Ida known myself for sure in the first day .