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Eric Experience
05-22-2013, 11:43 AM
Friends.
I have recently added a NCV3 to my fleet, while it waits for repair of the front diff the battery has gone flat. Measuring the constant drain on the battery I read 170ma, is this normal? can some one who has one of these measure there battery drain for me? Thanks Eric.

wayneskid
05-22-2013, 02:01 PM
Friends.
I have recently added a NCV3 to my fleet, while it waits for repair of the front diff the battery has gone flat. Measuring the constant drain on the battery I read 170ma, is this normal? can some one who has one of these measure there battery drain for me? Thanks Eric.

What instrument are you using to make the measurement? And where are you connecting to make the measurement?

icarus
05-22-2013, 03:17 PM
A clamp on DC ammeter is a good tool to use to measure current, idle or otherwise. I am away from my van, but when I get home I will measure mine. Intuitively, it sounds about right, perhaps a bit high.

Icarus

segler
05-22-2013, 05:46 PM
170 mA is not out of line if there is some small current draw for vehicle systems, such as radio, clock, electronics always-on memories systems, maybe even gps for E911. Mine draws about 70 mA.

That said, if you use the vehicle at least a couple times a week, the battery won't even notice this draw.

By the way, how does a clamp-on ammeter measure DC current? AC yes, but DC?

icarus
05-22-2013, 06:12 PM
You have to buy an AC/DC clamp on. Fluke makes a number of them and Sears actually sells a pretty good one for under $100.

http://www.sears.com/craftsman-digital-clamp-on-ammeter/p-03482369000P?PDP_REDIRECT=false&s_tnt=39869:4:0

Invaluable for doing solar or other battery work.

Icarus

PS mine read .179 amps as well, so it sounds "normal".

wayneskid
05-23-2013, 08:04 AM
DC clamp meters use a Hall effect sensor. Use Google for details.


Sent from my iPhone using Tapatalk

showkey
05-23-2013, 01:01 PM
170 mA is not out of line if there is some small current draw for vehicle systems, such as radio, clock, electronics always-on memories systems, maybe even gps for E911. Mine draws about 70 mA.

That said, if you use the vehicle at least a couple times a week, the battery won't even notice this draw.

By the way, how does a clamp-on ammeter measure DC current? AC yes, but DC?


Sorry........but i disagree with the above if the measure current draw of 170ma is done with an accurate meter and measured after the CAN system goes to sleep ........then 170ma is too high and some device is staying on. Assuming normal accessories, if something was added alarm, blue tooth, navi, etc 170ma could be normal for that setup but could cause problems because it is excessive especially for a single battery.

Normal parasitic draw should close to 50ma +\- 20ma. 170ma draw has the potential to run the battery down to a no start condition if the van is left parked for several days. By several days I would guess 5 to 7 days depending on many variables including battery size, condition, temp etc.

If the van is run daily 170ma draw would not normally be noticed. A normal modern car will draw 20-50ma. There are other threads on this topic.........another manufacture had blue tooth phone connection staying on ......drawing 200-250 ma typical customer complaint was leave my car at the airport.......4 days later come back to no start.
Radio or internal parts in the radio staying on after key off is a common problem........but testing is the only way to determine what circuit and what device on the circuit is staying active.

It is common for the CAN system to stay active for several minutes after key off.......then the system will go to sleep..........so it is important to watch the draw over time. Other manufactures CAN system can stay active for 20 minutes.

The quality of the tool and technique used to measure draw is critical in determining what is excessive.

Aqua Puttana
05-23-2013, 01:17 PM
Sorry........but i disagree with the above if the measure current draw of 170ma is done with an accurate meter and measured after the CAN system goes to sleep ........then 170ma is too high and some device is staying on. Assuming normal accessories, if something was added alarm, blue tooth, navi, etc 170ma could be normal for that setup but could cause problems because it is excessive especially for a single battery.

...
I agree, not that you need my support.

Eric tends to pick up ambulances and fleet vehicles. Maybe there is some aftermarket GPS location or vehicle operation recorder that is on all the time? vic

showkey
05-23-2013, 05:07 PM
I agree, not that you need my support.

Eric tends to pick up ambulances and fleet vehicles. Maybe there is some aftermarket GPS location or vehicle operation recorder that is on all the time? vic

:cheers:

The other sticking on device I have heard lately is the backup camera (after market not MB).........screen blank camera on.

Eric Experience
05-24-2013, 11:44 AM
Showkey and Vic.
Thanks for your input. 170ma does flatten the battery in about a week. This is not good enough for me so I must find a cure. I have gone through all the accessories and unplugged them. I suspect the problem is in a dome light delay off, my reasoning is that if I switch the lights on I can see the current rise but if I take the globes out and turn the lights on I see about 3 ma per light rise. This may be the the link to the door open icon, I would like to rewire the lights to the older style instant off. At the moment I am disconnecting the battery when parking the vehicle, a pain. Eric.

Aqua Puttana
05-24-2013, 12:20 PM
... At the moment I am disconnecting the battery when parking the vehicle, a pain. Eric.
Eric,
Physically disconnecting at the battery? I believe that NAFTA NCV3's have some sort of a battery switch in the area of the driver footwell. :idunno:

I don't drive my wife's buick very often. I often find myself watching as I leave at night because her auto dim down lights catch my eye. (Her interior lights catch my eye, not her headlights... well not as I'm walking from the car anyway.) My T1N only has the dash inset light to worry about.

Keep us posted. vic

wayneskid
05-24-2013, 02:40 PM
Eric,
The battery disconnect is called a "battery isolating switch" in my 2008 Freightliner manual. And Vic is correct it is located to the right of the accelerator pedal in the driver's footwell.

showkey
05-25-2013, 04:22 AM
Showkey and Vic.
Thanks for your input. 170ma does flatten the battery in about a week. This is not good enough for me so I must find a cure. I have gone through all the accessories and unplugged them. I suspect the problem is in a dome light delay off, my reasoning is that if I switch the lights on I can see the current rise but if I take the globes out and turn the lights on I see about 3 ma per light rise. This may be the the link to the door open icon, I would like to rewire the lights to the older style instant off. At the moment I am disconnecting the battery when parking the vehicle, a pain. Eric.

One troubleshooting method is get the draw exist and unplug fuses until the draw returns to normal.

That should ID the circuit involved.........next find all the items on that circuit disconnect each one, one by one until the draw returns to normal levels. That should lead the item staying on:thumbup:
Not easy on the sSprinter because the shop manual is so bad it hard to find the complete circuit diagrams for all the fuses that includes every branch and every wire.

Eric Experience
05-25-2013, 10:14 AM
Showkey and Vic.
Thanks again but may be I am wasting your time. My 315 is German built top of the speck passenger, [ex Ambo] it does not have any pedals on the left side, I have pulled every fuse I could see but was not game to leave them all out as I could get them mixed up. When I pulled the fuses the draw would drop a little with some fuses but none gave a dramatic drop. I pulled the wires from the busbar on the battery terminal one at the time and got a drop on two wires, The bigger drop was on the cct that feeds the lights. The German vehicles do not have a switch in the earth lead for good reason because if that switch is opened while the motor is running its good night to your electronics. The reason this happens is because the output of the alternator is a series of pulses it confuses the voltage regulator between pulses so you get spikes that can go to 100 volts. Not a risk I am prepared to take. If I can not sort this i will switch the light cct of when i park the vehicle. Thanks again Eric

icarus
05-25-2013, 03:46 PM
The NCV3 has a negative battery terminal quick disconnect, directly above the accelerator peel. Simply put in the button and lift the cable off the terminal post. Couldn't be easier!

Icarus

Eric Experience
05-27-2013, 12:07 PM
Friends.
In the original post I asked if some one who owns a NCV3 could measure the battery load at rest. I have had one response which is disputed by others, is there any chance of another response? Eric.

Amboman
05-27-2013, 12:59 PM
170 ma current draw is unacceptable in any vehicle,
I would clean all light globe sockets and WD40 them, moisture and dirt does that.

icarus
05-27-2013, 04:24 PM
HMMM,

I guess I will have to double check mine. Perhaps I didn't zero the met. .179 is a bit too high.

Icarus

autostaretx
05-27-2013, 04:32 PM
is there any chance of another response?
On my T1N, it's about 35 milliamps, which matches the "35 to 50" range given in the T1N service manual.

I'd be extremely surprised if (even) an NCV3 required more than 50 milliamps.
Fun question to ask a dealer's "Service Advisor"...

--dick

icarus
05-27-2013, 05:28 PM
I just noticed that my clamp on, was not closing when I checked, ergo it is an erroneous reading. I need to take something apart to get to a place I can get a good reading.

Busy to day , perhaps later this afternoon,

Icarus

autostaretx
05-27-2013, 10:48 PM
I need to take something apart to get to a place I can get a good reading.
Remember that you can also clamp around the negative cable instead of the positives.
The current reading will be equally valid.

--dick (who has the "luxury" of a T1N, where the positive wires are easily accessible)

Eric Experience
06-01-2013, 11:31 AM
Friends.
An up date on the battery drain problem. I found a programmable module that can used to raise idle speed as well as other functions, it is powered directly from the battery and was on all the time, I unplugged it and the ever thing still worked but there was a flashing icon on the dash so I rewired it to run on D+. all OK. draw down now was 50ma. I then found the 50ma was powered by an 80 amp fuse on the battery terminal so I put a switch in the wire. draw down now is 3ma rising to 4ma every tick of the clock. I can live with that. Eric.

Eric Experience
06-24-2013, 11:21 AM
Friends.
A further follow up. I have just returned from a trip and had no electrical issues as the result of my mods. The only thing that did cause a minor problem is the clock, When l could see a one second pulse on the 3 ma I assumed the clock was still running but apparently not, the clock starts of from zero each time I turn the 50 ma to the ecu off and on again. Eric