Battery Drain - Winnebago ERA Conversion

[cguise]

Current Problem: The Sprinter has a significant battery drain. The Chassis battery dies in about two days if it is not used.

Background: We have a 2008 Dodge Sprinter 2500 that was converted by Winnebago into an ERA 170 Class- B motorhome. We took delivery of the motorhome in 2009. The system operated normally from new (we think).

Possible Symptom: The vehicle fuse for the radio blew several months ago and we replaced with another 15amp fuse. This was fuse number 10 on fuse block F55/2 (the lowest of the three blocks in the fuse block near the hood release). During the conversion a Jensen JRV 210B radio was factory installed in our Winnebago ERA Conversion. We believe the radio is the only consumer on that particular fuse.

Possible Symptom: The Jensen JRV210B is connected to a Sirius receiver. Even when the receiver is off the Sirius receiver still reads “Sirius Connect” which implies that it is drawing power through the radio.

First Round of Testing: We used a Klein Tool CL2000 tester and used the clampon style for the initial round of testing. The tester was zeroed and set to DC amps. We clamped the tester around the negative wire that connects the negative battery terminal to the fire wall. With the ignition off and key out of ignition the initial draw was 1.1amp. Upon pulling fuses we determined that the battery drain was partly attributable to the vehicle fuse for the radio (number 10 on fuse block F55/2). With fuse 10 pulled the drain went from 1.1amp to 0.3amp. We pulled all of the other fuses under the dash near the hood release and all of the fuses under the driver’s seat and could not get any more reduction of the remaining 0.3 amp. At this time of initial testing I did not have the tools to get access to the preliminary fuse box F59 in the battery footwell compartment.

We also used the factory installed Radio Power - House/Chassis Battery Switch to verify these results. When Radio power is switched to the House Battery the current draw drops by 0.75amps. When switched back to Chassis the draw reappears.

I contacted Winnebago and they were extremely helpful and responsive, the technician was surprised by the amount of draw from the radio. (As was I). The technician suggested that I try testing using leads instead of the clamp-on style testing due to accuracy concerns.

Second Round of Testing: Using the same tester I disconnected the negative wire from the firewall. The tester was zeroed and set to DC amps. I attached one lead to the firewall connector and the other to the negative battery terminal. The tester read 1.25amp with the engine off, key out of the ignition, and doors closed. I removed every fuse including number 10 again however this time there was no reduction in the draw it remained steady at 1.25amp.

I was able to access the preliminary fuse box F59 in the battery footwell compartment. To test this I reconnected the negative wire to the fire wall. I then connected my tester to the positive battery terminal and the other side to the preliminary fuse box. I removed each individual wire from the preliminary fuse box and again I saw no reduction in the draw. Still 1.25amps, my frustration was rising.

In addition to the preliminary fuse box connections there were two other connections to the battery not running through the preliminary fuse box. The first is a red wire that runs along the floor towards the rear of the vehicle along side of the driver’s seat (it was labeled 300 in handwriting). When I put my tester in line with the positive battery terminal and this wire I get a zero reading. The second is a black wire that exits through the side of the battery box towards the rear of the vehicle. When I put my tester in line with the positive battery terminal and this wire I get the same 1.25amp reading. (now I think I am using the tester wrong).

Thinking it was still the radio I tried one more thing. I put everything back together and disconnected the negative wire from the firewall and connected the tester inline between the firewall connector and the negative battery terminal. Again I had the 1.25amp draw. I then removed the radio from the dash. I unplugged the radio connecter and there was no appreciable reduction in the draw. I plugged the radio back in. I then used the tester with the clamp-on method to check the individual feeds to the radio. Using the clamp-on method I was getting a 0.6amp draw on two of the leads and a 0.2amp on the third lead. Based on the radio documentation the leads are for the memory (always on), radio power (ignition switched) and dimmer. I am just not sure which is which because the documentation in the radio book does not match the actual plug.

After this test I am back to thinking it is the radio. But I am also stumped by all of the inline tests that I performed. Sorry for the long-winded explanation but I wanted to put all of the info I have out there to make sure I was not leaving out an important fact.

A few thoughts and questions:

1. Am I using the tester wrong that I am getting different readings using the clamp-on method versus the lead/in-line method? Or is there some other explanation.
2. I am thinking the 1.25amp draw I am reading when using the tester with leads inline is not accurate but I do not know what is causing this.
3. Is the radio the red herring in this scenario is there another source of the problem out there I am missing?
4. Is there another fuse box that I am not finding? In the first round of testing we even checked the motorhome house fuse panel in the rear.
5. Any ideas on what is causing the battery drain?


Thanks,
Clif

[autostaretx]

1. Am I using the tester wrong that I am getting different readings using the clamp-on method versus the lead/in-line method? Or is there some other explanation.

Clamp-on ammeters are not as accurate as in-line ammeters.
Since the draw you're seeing is within the range of most decent in-line ammeters, i'd go that route.
Clamp-on ammeters need to be "calibrated" for the wire they're clamping.. you see to be doing that.
You can do a small self-test by reversing the direction of clamp.. so that the meter reads negative instead of positive.
(hopefully the reading will be the same). Nearby magnetic fields can affect a clamp-around reading.

2. I am thinking the 1.25amp draw I am reading when using the tester with leads inline is not accurate but I do not know what is causing this.

See above. But in-line meters can affect readings, too... measure the voltage *across* the in-line meter to verify that it's not affecting things by being a too-high resistive insertion.

3. Is the radio the red herring in this scenario is there another source of the problem out there I am missing?

Well, i'd unplug the radio and see how the symptoms change. Leave it off for days. The radio harness cut be cut behind the dash and shorting to the frame (etc.etc).

4. Is there another fuse box that I am not finding? In the first round of testing we even checked the motorhome house fuse panel in the rear.

I don't have an NCV3... the T1N has three fuse areas: on the battery post, under the steering wheel, beside the driver's seat.

5. Any ideas on what is causing the battery drain?

Other folks (both T1N and NCV3) have found some relays stuck closed (burned/welded contacts) (such as fuel pumps, glow plugs, etc... any relay can stick)
The normal overnight draw should be on the order of 30 milliamps. (0.03 amps)
You could rig a ammeter tester with a battery (1.5v, 9v or the Sprinter's) and a resistor to create "known currents", such as a 12 ohm resistor on a 12 volt supply.. which should create a 1 amp flow. Test your tester.

The different modules talk to each other.. having some fuses pulled can cause them to set up bizarre current pathways.
Is your ash tray loose/out? Does that turn on the light which surrounds the cigar lighter socket?

good luck
--dick

[cguise]

Originally Posted by autostaretx

Clamp-on ammeters are not as accurate as in-line ammeters.
Since the draw you're seeing is within the range of most decent in-line ammeters, i'd go that route.
Clamp-on ammeters need to be "calibrated" for the wire they're clamping.. you see to be doing that.
You can do a small self-test by reversing the direction of clamp.. so that the meter reads negative instead of positive.
(hopefully the reading will be the same). Nearby magnetic fields can affect a clamp-around reading.

I do get the inverse reading when switching the leads or flipping the clamp-on

Originally Posted by autostaretx

See above. But in-line meters can affect readings, too... measure the voltage *across* the in-line meter to verify that it's not affecting things by being a too-high resistive insertion.

What should the voltage reading be to check this?

Originally Posted by autostaretx

Well, i'd unplug the radio and see how the symptoms change. Leave it off for days. The radio harness cut be cut behind the dash and shorting to the frame (etc.etc).

What would a few days gain me or what do you think would happen after a few days of having the radio unplugged.

Originally Posted by autostaretx

Other folks (both T1N and NCV3) have found some relays stuck closed (burned/welded contacts) (such as fuel pumps, glow plugs, etc... any relay can stick)
The normal overnight draw should be on the order of 30 milliamps. (0.03 amps)
You could rig a ammeter tester with a battery (1.5v, 9v or the Sprinter's) and a resistor to create "known currents", such as a 12 ohm resistor on a 12 volt supply.. which should create a 1 amp flow. Test your tester.

The different modules talk to each other.. having some fuses pulled can cause them to set up bizarre current pathways.
Is your ash tray loose/out? Does that turn on the light which surrounds the cigar lighter socket?

The whole thiing is baffling to me because I am getting a drain in so many places. What I thought would eliminate a few possibilities created more questions. THis is why I think it might be a tester problem. My other thought is that the effected system is getting ground from somewhere else, possibly the house rv battery. I may disconnect the house battery negative terminal too when doing my test so I can eliminate that. If it ends up being relays we may be taking it to the dealer. When it comes to electrical systems I know enough to be dangerous.

That is good suggestion on how to test my tester. Thank you for your quick reply. Clif

[icarus]

A clamp on ammeter may not be 100% perfect, but is a pretty good tool to have around! Sears sells a pretty good one for~$70 Fluke a great one for a couple hundred.

Icarus

[kendall69]

The way I have always found problems is pulling fuses. I had a guy install some off road lights on a Jeep, and another guy install a aux. braking system - then the battery drain started. I did this following and found it was the lighting guy that screwed up. I redid everything fro the lights to that battery and all was fine.

First, disconnect the positive cable to your battery. Second, using a 12 volt test light, connect the clip to the battery cable. Third, using a pair of vice grips or a small C clamp, connect the probe end of the test light to the positive side of the battery. The light should turn on if you have a radio with a memory.

Find you fuse box and remove the fuse from the fuse holder marked radio. After removing the fuse the light is still lit, that indicates there is power being drawn from another circuit. Remove the fuses one at a time until the light turns off. Once it does, diagnose all accessories on that circuit until the problem is found.

Read more: How to Find an Electrical Short in Your Car | eHow.com http://www.ehow.com/how_4877695_elec...#ixzz23HCQDGiH


With an RV you need also to be concerned with coach batteries and coach breakers.

[icarus]

A positive on/off switch on the battery neg. is a easy, quick way to keep long term battery drain in check. Most battery isolators that I have seen draw as much as 1/2 amp just to keep the relays energized,, not to mention any loads that are on, like the CO detector.

Icarus

[showkey]

Originally Posted by kendall69

First, disconnect the positive cable to your battery. Second, using a 12 volt test light, connect the clip to the battery cable. Third, using a pair of vice grips or a small C clamp, connect the probe end of the test light to the positive side of the battery. The light should turn on if you have a radio with a memory.

Find you fuse box and remove the fuse from the fuse holder marked radio. After removing the fuse the light is still lit, that indicates there is power being drawn from another circuit. Remove the fuses one at a time until the light turns off. Once it does, diagnose all accessories on that circuit until the problem is found.

Read more: How to Find an Electrical Short in Your Car | eHow.com http://www.ehow.com/how_4877695_elec...#ixzz23HCQDGiH


With an RV you need also to be concerned with coach batteries and coach breakers.

That method has a few problems with a modern car:

Radio memory
ECU memory ( more than one)
B-CAN

So the brightness of the bulb will vary with the draw, but you then must judge what norm is. The ammeter does this with a number about 30 to 60 ma is normal.

That method can also cause all sorts of codes in SRS,BCAN, ABS that can not be cleared with out a dealer visit.

You are looking for parasitic draw not a short as in blowing fuses short.

Stick with the ammeter and pull fuses and or harnesses until the draw goes to a normal level.

You are on the right track just your final troubleshooting technique to a conclusion needs work.

A few tips before you conclude the parasitic draw is high and it location:

Let the van go to "sleep" things like the entire BCAN system, all blue tooth connections, radio connections to other devices, plus hand free phone link, alarms, power locks, power windows all need to go into "sleep mode". Sprinter I think does this quickly but under some circumstances it can take a few minutes. This is especially true if the van has blue tooth hands free link.

It is also best to test the car in the same conditions the draw is showing, like radio on( during normal use) doors locked with remote etc..........you can still have the doors open but trip the latches closed to make the van think,the dors are closed. This technique checks all inputs to the BCAN like lock switches door latch switches........if a switch is intermittently sticking the system will not sleep causing the draw.

The radio is your prime suspect I would continue on that path but check the sat radio unit it could be staying on along with any amp systems if equipped. Some radios are connected to the BCAN so they are tied to the alarm as well.

[autostaretx]

Originally Posted by cguise

What should the voltage reading be to check this?

As little as possible. Hopefully less than a volt... preferably less than 0.25 volts.
The quality of your attachment of the ammeter wires (clamps versus pressing pin-probes) may have much effect.

I mis-typed:

The radio harness cut be cut behind the dash and shorting to the frame (etc.etc).

That should not have been "cut be cut", it should have been "could be cut", meaning that the cable may have been accidentally damaged.
I was not suggesting that you manually cut the cable.

In a T1N the Radio fuses (there are two) also power other devices... the same Great Brains designed your NCV3 Sprinter, so you may be seeing one of the other devices being at fault, only making it look like the radio. (i don't have an NCV3's wiring diagram).
(in the T1N, Fuse Block 1's Fuse 15 powers the amplified antenna and also goes to the CTM module, and Block 1's Fuse 8 goes to lots of places:
two anti-theft relays, the cigar lighter, the auxiliary heater control and all of the interior lights)

--dick

[glas1700]

Originally Posted by kendall69

First, disconnect the positive cable to your battery. Second, using a 12 volt test light, connect the clip to the battery cable. Third, using a pair of vice grips or a small C clamp, connect the probe end of the test light to the positive side of the battery. The light should turn on if you have a radio with a memory.

ALWAYS disconnect the negative cable from a battery first, never the positive cable. A wrench connected to the positive terminal that accidentally touches a nearby ground can turn red hot in seconds and cause a battery to explode.

[icarus]

Just the arc from shorting a wrench can explode a battery! I know,,,, I did it once. Mercifully no one was hurt! Rubber covered wrenches, putting a rag over the posts etc is cheap insurance,, and remove the neg first!

Icarus