How to determine parasitic load on the starting

Wetstuff · 06-13-2019, 02:43 PM

..battery. I have a 3-month-old starting battery from the largest, auto electrics supplier in the area. It keeps discharging. I have one of those 'smart' chargers that finally has displayed 'Battery Failure'. It will no longer accept a charge. (I have the trik-l-start not yet installed)

I was going to simply install an on/off switch at the + terminal, but thought it better to look for the problem than a workaround.

But... what sort of meter do you install between the main feed and + terminal to 'see' the flow of electrons? ...maybe a mystery lamp somewhere in the basement? ...???

Jim

SLOweather · 06-13-2019, 06:00 PM

A digital multimeter with a 10 amp DC current range would be a good place to start. Lift the negative cable and put the meter in series with it and the battery.

I had similar problems (but apparently not as bad) using a Harbor Freight trickle charger. I replaced that would an older Die Hard model with more current and that fixed it.

Wetstuff · 06-14-2019, 07:54 AM

Thanks, Slo... I may have to remove and haul the battery to the dealer first. I have not checked after the charger read 'INOP', but when the radio quit, I assumed the there was no more juice to be had. Before I pull it, I will see if I get anything. Thanks.

Jim

BobC · 06-14-2019, 10:24 AM

These are relatively inexpensive and effective. The added advantage is that it will monitor usage over time. Once you've tracked down your current issue, you can install it so you can monitor ongoing power usage:

https://www.ebay.com/itm/17305814208...m=173058142084

imnprsd · 06-19-2019, 05:39 PM

It's not uncommon for a new battery to have a bad cell. Since your engine battery is no doubt sealed, your only other alternative to prying off the caps and voiding your warranty is to take the battery back to your store and have them put a battery tester on it. (Load test) They will replace your battery free of charge if they find it is defective.

As for parasitic draw, I have found these items are worth checking:

1) Solenoids a) Boost; b) Battery Disconnect

2) Ignition switch

3) Alternator Diodes shorting to ground

4) Step circuitry

5) Inverter

What type of coach do you have?

Does your inverter have a charger built into it or is your charger separate?

DryCreek · 06-19-2019, 07:14 PM

Quote:

Originally Posted by imnprsd

It's not uncommon for a new battery to have a bad cell. Since your engine battery is no doubt sealed, your only other alternative to prying off the caps and voiding your warranty is to take the battery back to your store and have them put a battery tester on it.

I haven't bought a totally sealed aftermarket battery in years. The last one I saw sealed came with a truck we bought in 2003.

VSPA · 06-20-2019, 07:07 AM

I have an Itasca 35F and in conjunction with fining a bad fuse in the battery disconnect solenoid I installed a manual battery disconnect on the coach batteries for added "insurance"

Wetstuff · 06-20-2019, 07:35 AM

Thanks, imn... This is a great place to learn stuff. Mine is a 2002, 8.1 vortex, Workhorse chassis under a 27' Win Sightseer. Here's where ignorance is on display: Pretty sure.. my shorepower gizmo only charges the house batteries. But, I got the 5 amp Trik-L-Start being installed this week to maintain the starting battery. With the step disconnected, I am only loosing .5 amp at the moment.

Since we civilians have access to cheap Chinese tools I have both a smart charger and 'gets hot' load tester. Between all my 'stuff' I have seven that require battery-start. (I even have a battery tester for AAAs, etc)

Creek, The battery I returned was sealed. The last two mower batteries I got at Home Depot were also sealed. The battery dealer in my town is HUGE, you'd think them nuts for having so much space and service bays for 'just batteries' but the area is mostly rural and I don't think farmers buy batteries at WalMart. (where I got a capped battery last year)

Having spent years watching little balls in the eyedropper and stressing about not using 'distilled water', I like the idea of sealed. I'm not quite there with those fancy aviation batteries, but we are all likely headed there.

Thanks, guys. Jim

Leevormelker · 06-20-2019, 09:03 AM

Quote:

Originally Posted by SLOweather

A digital multimeter with a 10 amp DC current range would be a good place to start. Lift the negative cable and put the meter in series with it and the battery.

I had similar problems (but apparently not as bad) using a Harbor Freight trickle charger. I replaced that would an older Die Hard model with more current and that fixed it.

A simple multimeter wired in series with eather the lead going to the + or - lead will allow you to measure the loss. Pay attention to the zero setting of the meter. Those inexpensive meters man not zero properly.

Kayak73 · 06-20-2019, 03:17 PM

dup

DryCreek · 06-20-2019, 08:33 PM

Quote:

Originally Posted by Wetstuff

Creek, The battery I returned was sealed. The last two mower batteries I got at Home Depot were also sealed. The battery dealer in my town is HUGE, you'd think them nuts for having so much space and service bays for 'just batteries' but the area is mostly rural and I don't think farmers buy batteries at WalMart. (where I got a capped battery last year)

We buy all of our tractor and "other" batteries at a local small-town auto parts store. They carry Continental brand batteries. I bought one for my old YJ just this Monday. It has caps that you can pry open and check the water level in.

rverosloff1 · 07-04-2019, 07:50 PM

I am having this problem of my engine battery going dead within 24 hours of not being plugged in on my 2006 Journey, how do I check the things you mentioned to see if they are the problem?

SLOweather · 07-05-2019, 12:05 AM

How old is the battery? Does it need water?

Wetstuff · 07-05-2019, 07:47 AM

Osloff... If you are ignorant in this area, like me, start with SLO's suggestion - get the battery tested. If you do not have a really smart electrical person in your area - a simple on/off terminal switch is ~$20. ..if you do not know the age of the battery - get a new one; you will know it going forward.

Jim

rverosloff1 · 07-05-2019, 06:46 PM

the journey wouldn't start this sumer after just putting new batteries in last summer the repair guy had to come to us as it wasn't going anywhere. he diagnosed a bad cell in one of the two engine batteries and said the three coach were fine and sold us two new engine batteries. the journey started fine but we are back to where we were before the new batteries as it has been doing this since we got her 3 years ago with going dead within 24hour. sometimes
the low battery indicator would come on while driving down the interstate. It has been a real problem for us. we took it to 2 different dealers and a couple of repair shops and nobody can help us except to sell us new batteries.

imnprsd · 10-27-2019, 02:04 AM

rverosloff1... What was your solution?

Morich · 11-22-2019, 03:18 PM

Quote:

Originally Posted by rverosloff1

the journey wouldn't start this sumer after just putting new batteries in last summer the repair guy had to come to us as it wasn't going anywhere. he diagnosed a bad cell in one of the two engine batteries and said the three coach were fine and sold us two new engine batteries. the journey started fine but we are back to where we were before the new batteries as it has been doing this since we got her 3 years ago with going dead within 24hour. sometimes
the low battery indicator would come on while driving down the interstate. It has been a real problem for us. we took it to 2 different dealers and a couple of repair shops and nobody can help us except to sell us new batteries.

This is a classic example of WHY we need to do the study to understand for ourselves! It is often not that they can't find the problem but more that they don't as it is so much better for them to sell new batteries!
New batteries may be defective and fail but they can also be ruined by other things like being charged too fast for too long so that they boil dry. Lots of small points are needed to make batteries last but the most often found recommendation is "change the battery"!
We often read about using a meter but that needs to have some caution thrown in to avoid blowing a meter. common meters are often ""multi-meters and can be used different ways if we change the settings and how we connect them.
For testing battery drain, we need to be sure we set the meter to the ammeter portion and that is a meter with enough capacity to handle the current we are going to put though it. On an RV and just the 12 volt DC from parasitic drains, a 10 amp setting will be safe but give it some thought first.
Then connect the meter so that the current runs through the meter which requires a different method than testing voltage. Since the ground side of the battery is safer to open, I remove it, connect the meter to ground and then to the battery. Fewer sparks, less danger of blowing up any collected gas from the battery.

BobC · 11-22-2019, 04:47 PM

Multimeters with a clamp-on current probe are much easier to use. Just make sure you get one that measures DC current as well as AC. Many are AC only.

bobmac · 11-24-2019, 06:51 PM

If your new battery gets depleted quickly, it could be parasitic loads although if they are part of the engine, difficult to determine and even more difficult to correct. I had an E450 class C that had a significant parasitic load. Found the best way to avoid depleting the chassis battery was to disconnect the battery ground wire (or you could add a switch) when I was storing the coach for anything more than a few days. Good luck.

rckmtn12 · 11-24-2019, 07:47 PM

I have a 2012 35f and had charging/drain problems for the last year. I also put the battery disconnect switches on the battery. The rig died on me last week and I got off my duff and started troubleshooting. Turned out both of the factory disconnect relays Had lots of corrosion inside of them. They are not hermetically sealed and on one relay it would not change state and the other one had a high resistance on the contacts from corrosion. I replaced both relays coated all connections with DeOxIT and they work perfectly now. I also cleaned and doxit coated batteries, chassis ground point and the power junction on the frame under the passengers area.All works great now.