Electrical problem..help !!!!!

[rumme]

So I just found out that my used 4runner , has some type of parasitic electrical problem. Something is draining my battery power when my truck is not running. Its taking about 1 volt out of the battery per 24 hour period.

I took the lighter out of the light socket...the radio is turned off, no lights are on inside or outside of the vehicle , the small LED date/time window is not lit up when the vehicle is off....

any idea what could be draining power from my battery ?

I just bought a new battery, cause the battery that was in the 4runner when I bought it, went down to 4.8 volts , over a 6 day period when I did not start it up...

if I cant figure this out, then I guess I have to put a inline cutoff switch on the positive side of the battery terminal, and manually disconnect it whenever im done driving...that would be a pain in the butt.

Something does seem screwy with the lighter output....I have 1 of those solar lighter battery chargers, that plug into the lighter input, and keep the battery fully topped off , when the vehicle is not running. I plugged that into the lighter socket, and then tryed to measure the voltage on the positive and negative battery cables { unhooked from the battery} , and it was reading only 10 volts , when it should be reading about 20 volts, which is how much the small solar panel puts out to keep the 12 volt vehicle battery charged up.

Ive used these small solar panels before on other vehicles and they worked great via the lighter socket...so something is odd with this 4runner.

 

[the_dingman]

You could have a small short somewhere, or the battery could just be going bad.

Get a multimeter, disconnect the positive battery terminal and put the meter in-line with the terminal and the positive lead, measuring amps. This will tell you if there's a significant draw. I've never done this, but someone else can probably tell us what a normal draw is with everything off.

 

[rumme]

You could have a small short somewhere, or the battery could just be going bad.

Get a multimeter, disconnect the positive battery terminal and put the meter in-line with the terminal and the positive lead, measuring amps. This will tell you if there's a significant draw. I've never done this, but someone else can probably tell us what a normal draw is with everything off.

this is a new battery..just bought it yesterday.. put it in the truck..it measured 12.6 volts....measured it just now..and its at 12.5 volts...

I already know theres a draw somewhere...I just dont have any idea where its drawing from...

the radio is off...no lights are on...so theres nothing that I can see that is drawing power off the battery..but something is definitely drawing the battery down..

boy I hate electrical problems like this...

something does seem screwy with the lighter socket...but if I dont even have the lighter in the socket, I cant see how the socket would be drawing power from the battery...

there is a aftermarket radio in the vehicle..but when I turn the key off, the radio goes off...so I dont think the radio is the problem.

 

[rumme]

You could have a small short somewhere, or the battery could just be going bad.

Get a multimeter, disconnect the positive battery terminal and put the meter in-line with the terminal and the positive lead, measuring amps. This will tell you if there's a significant draw. I've never done this, but someone else can probably tell us what a normal draw is with everything off.

I cant imagine the normal draw would be 1 volt in a 24-48 hour period...this would mean that in 2-4 days of not starting the vehicle, the battery would be completely drained..

 

[rumme]

Maybe the simpliest way to try and diagnose the problem, is to go to the fuse box, and pull out 1 fuse at a time , while measuring the amp pull....in between the battery positive terminal and positive motor cable with my multimeter...

I think I try that now....

 

[rumme]

looks like I have to take this to the dealer tommorrow...

anyone know how many Mah's the onboard computer/accessories is supposed to be drawing when the vehicle is not running ?

 

[RotaMan2]

Try disconnecting the battery terminal on the alternator side. Mine shorted out and was drawing from there. It charges just fine, but draws when the motor is turned off. I changed out the alternator and now its fine

 

[rumme]

Try disconnecting the battery terminal on the alternator side. Mine shorted out and was drawing from there. It charges just fine, but draws when the motor is turned off. I changed out the alternator and now its fine

I dont know what you mean..

the battery terminal on the alternator side ? the positive lead on the alternator ?

can you be more specific ?

 

[RotaMan2]

on the alternator itself there should be a large wire, white color. Its held on by a 10mm nut. take that out and check your voltage reading on the battery, Wait an hour and take another reading see if there is a significant voltage drop. If no change in voltage change alternator.

If there is a voltage drop, disconnect fuses in engine compartment area. Such as the big 30 amp ones first an so on. Electrical short is a pain, but by eliminating each circuit at a time u will find the culprit. good luck

 

[rumme]

took my V6 dog, to the dealer today...$150 it cost for them to find the parasitic electrical drain problem...

it was a damn aftermarket, GPS/communication device..it was a black box, mounted under the steering wheel behind the plastic molding...it was drawing about 1/2 amp when the vehicle was off...