Electrical power loss

[twothirteen 10+ year member]

Hello all,

I'd like to describe a brief symptom of the problem my truck is experiencing, and have one of you with more knowledge help me out of my predicament.

Problem: When I let my vehicle sit for ~2 days straight it would gradually lose power and eventually die to the point of my vehicle losing the ability to start up. That was in the summer, and as a frequent drive I wasn't very concerned since I drove very often. It's now winter, and I can hardly let my vehicle sit for 20 minutes before it needs a jump to get it started.

I have paid to have my electrical system tested, and the company found no shortages. "There are no problems with your electrical system", the guys at the shop told me. I asked why it would die after sitting for a while and they suggested leaving my truck there for a night or two to do some tests while it was dead. I opted not to since I had to move cities.

Point in case, whilst running, my electrical system is just fine. It typically reads ~14.5 - ~14.9 on my Cap.

tl;dr My battery is draining to very low amperages while my engine is off. When I start it back up, the battery recharges to full really fast.

Now some specifics.

Here's my setup...

-340amp alternator ran 0g to Optima Redtop & properly grounded.

-Optima to 0g to 300A fuse to 20' (through firewall) to 300A fuse into a distribution block.

From the distribution block:

- path 1 - 0g wiring to the battery capacitor, 0g positive out of the cap into the 2000w mono block rockford amp. From the amp there's 0g grounding wire into the capacitor. From the capacitor there's 0g grounding wire to the chassis. (its a 50 farad cap.. if that matters at all)

- path 2 - 2g wiring from the capacitor to a JBL 450w amp, then the amp is grounded via 2g to the chassis.

Side note: I just disconnected the 20' 0g wiring from the red top and back, and left my truck to sit for the night to check if the battery leak is positively being caused by the sound system.

Any and all questions and/or ideas, are welcome. I'll check back frequently and post all current updates on the main topic.

Click to read more...

 

[matt_bennett05 10+ year member]

Yeah man sounds to me like you have either weak batts or something's consuming power while the vehicle's off.

 

[twothirteen 10+ year member]

I've been having the problem before & after buying a brand new red top Optima. (I bought a Kinetic for installing once I figure out this problem)

 

[TheUnderFighter 10+ year member]

Probably the capacitor. Throw it in the trash and see if it's any better.

 

[twothirteen 10+ year member]

I'll try removing it completely. I'll check back with those results in day or few.

Since I've explained my system setup & at least a few of you have read it, I'll ask; How would you recommend I connect my 2nd battery, and should I buy an isolator? I'd prefer to have both the redtop and the little optima pushing my sub since my alternator & the big 3 can handle the recharging of both batteries.

 

[>>SQL<< 10+ year member]

I had the same problem on an off-road buggy I have.

I changed the alt out to a higher output one

I the wire I ran to the alt (to the exciter) that was always on (I was told this was correct)

Well my battery would run down over night

Once I figured out the problem I changed the wire to the alt to a switched (on and off with the key) and problem solved.

Don't know if this will help.

As for the above suggestion about removing the cap, while we all tend to frown on caps cause they are all hype and do nothing to strengthen the electrical, it is not really possible that it is draining your system.

 

[twothirteen 10+ year member]

I had the same problem on an off-road buggy I have.I changed the alt out to a higher output one

I the wire I ran to the alt (to the exciter) that was always on (I was told this was correct)

Well my battery would run down over night

Once I figured out the problem I changed the wire to the alt to a switched (on and off with the key) and problem solved.

Don't know if this will help.

As for the above suggestion about removing the cap, while we all tend to frown on caps cause they are all hype and do nothing to strengthen the electrical, it is not really possible that it is draining your system.

Crispin, this "I the wire I ran to the alt (to the exciter) that was always on (I was told this was correct)" is a bit unclear to me.

Are you saying you added a current switch on the power wire from your alternator to your main battery? That would obviously make no sense for driving and listening to music. Are you saying your alternator draws power at night since it's high-output and must flip the switch to off while the vehicle sits?

As for the battery cap, it was given to me for free when I bought my sub & amp. I figured its addition could do no harm, and if it does no good electronically, it at least has a digital output reading to show me the draw of my system at any given time. ;0) Though some could argue it adds ~20lbs to the back of my truck causing a higher loss in MPG at the expense of a digital readout which can be bought for cheap and installed at virtually no weight added.

.. that's just my counter-balance speaking. ;Op

 

[>>SQL<< 10+ year member]

Sorry to clarify

I have a custom built buggy

I added a higher amp alt from a GM

In order for the alt to work it needs 12 volts to one of its wires

When I first wired it up I connected that wire to the battery (I was told that was correct)

This wire is called the exciter wire, all alts except for the GM 1 wire style have them

having it powered all the time drained the battery when I wasn't using the buggy

Anyway I switched the wire to one that goes on and off with the key - solved my problem

I noticed you had an aftermarket alt, I just thought it could be a possibility that it was not installed correctly. Most likely not.

However something is drawing a lot of power if your car goes dead so quickly.

 

[twothirteen 10+ year member]

Thanks for clarifying that, I'll research this as it is a possibility.

 

[TheUnderFighter 10+ year member]

Sorry to clarify
I have a custom built buggy

I added a higher amp alt from a GM

In order for the alt to work it needs 12 volts to one of its wires

When I first wired it up I connected that wire to the battery (I was told that was correct)

This wire is called the exciter wire, all alts except for the GM 1 wire style have them

having it powered all the time drained the battery when I wasn't using the buggy

Anyway I switched the wire to one that goes on and off with the key - solved my problem

I noticed you had an aftermarket alt, I just thought it could be a possibility that it was not installed correctly. Most likely not.

However something is drawing a lot of power if your car goes dead so quickly.

That makes a lot more sense.

Any results on the issue OP?

And I was really only giving you **** about the cap. I don't think it could hurt anything (aside from your MPG), but it certainly doesn't help anything. And personally when I talk to anyone around town and then they say they "absolutely must have a cap" I immediately dismiss them as knowing anything about what they're doing.

As for the voltage meter, I just bought this: Mini Blue LED Volt Meter DC 7-20V Doesn't Require Power | eBay

Works just dandy, and I can dial it in to calibrate it on the back. They have it in a couple different sizes and colors.

 

[twothirteen 10+ year member]

Well guys I'm at a standstill.. I determined it's not to do with the sound system via cutting off the power to the sound-system, jumping the car and letting it run for a while, then letting it sit for the night. Turns out the battery drained almost completely. To the point of being unable to start it.

I know first hand that my alternator is installed correctly.. since I installed it

There's some odd noises coming from the left rear passenger doors automatic locking system. I think it's constantly draining battery juices.. I wonder, can I disconnect the electronic system from constantly attempting to lock this door? (I can manually lock it too) ......I think there's a fuse for it so I'll check that out, pull it out, and report back after charging and letting my vehicle sit.

 

[TheUnderFighter 10+ year member]

^ you can always take the door panel off and just unplug the harness.