Engine Battery Discharge Advice Please (1 Viewer)

May 7, 2013
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On our 2nd MH now a AutoTrail Savannah which we're absolutely delighted with
Our battery charges to 13V + after running the engine for 30 minutes approx.
The battery is a YUASA 95 amph.
After 3 days of inactivity the voltage drops to 11.5 or less and after 4 days it has dropped to 11V and the MH requires a jump start.
Can I ask is the voltage drop irrefutable evidence that the battery is knackered?
I ask this question because I'm taking it back to the dealer who wants to run a 24 hour test on the battery before agreeing (hopefully) to renew it and I don't want to be fobbed off by some inappropriate statement!
Thanks again in anticipation
Ian
 
Sep 10, 2012
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Take the battery out of the vehicle and charge it with a 4 stage charger for 24 hrs.
Measure the voltage when fully charged (totally disconnected) and then every 2 hrs.
If the voltage continues to fall over 24 hrs then its fubar‘ed.
 
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Don Quixote

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Not long enough, but a little common sense helps..........
Our battery charges to 13V + after running the engine for 30 minutes approx.
The battery is a YUASA 95 amph.
After 3 days of inactivity the voltage drops to 11.5 or less and after 4 days it has dropped to 11V and the MH requires a jump start.
Can I ask is the voltage drop irrefutable evidence that the battery is knackered?
I ask this question because I'm taking it back to the dealer who wants to run a 24 hour test on the battery before agreeing (hopefully) to renew it and I don't want to be fobbed off by some inappropriate statement!
Thanks again in anticipation
Ian
As you have run it / charged it via your engine and then left it for 3 days and it has dropped to 11.5 the battery is U/S period. It needs replaced now. I would also recommend a battery master which Jim sells here on the forum, which will therefore give you no further problems with the battery after it's replaced.

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Feb 9, 2008
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The 13V reading confirms your alternator is working as it should and charging your battery. The battery voltage drop over 3 days is an indication of A, a drain being placed on the battery which would need to be investigated further. (just replacing the battery with a new one would soon result in the same problem. B, Make sure your habitation 12V services are being fed from your leisure batteries and not your cab battery. C, The battery no longer capable of holding it's charge. This could be for a number of reasons, a sulfated battery etc.
Let the dealer do his stuff and wait till he responds before doing anything else. It may be as simple as need a replacement battery due to age. They don't last forever.
 
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IanF
May 7, 2013
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On our 2nd MH now a AutoTrail Savannah which we're absolutely delighted with
As you have run it / charged it via your engine and then left it for 3 days and it has dropped to 11.5 the battery is U/S period. It needs replaced now. I would also recommend a battery master which Jim sells here on the forum, which will therefore give you no further problems with the battery after it's replaced.
Thanks I should have said I already have one of Jim's battery master fitted along with 2 solar panels which maintain my leisure batteries upwards of 13.7 V
 
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IanF
May 7, 2013
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On our 2nd MH now a AutoTrail Savannah which we're absolutely delighted with
If in doubt just replace it.
If, as you say, it has a BM fitted and solar your battery is cabbaged.

An engine battery will cost around £60 at a guess.

Thanks Pappajohn but I do hope to get Marquis to replace it for me as I don't think you can say it's fit for purpose if you have a MH which can't motor without a jump start every 4 days or so
 
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Aug 6, 2013
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Our battery charges to 13V + after running the engine for 30 minutes approx.
The battery is a YUASA 95 amph.
After 3 days of inactivity the voltage drops to 11.5 or less and after 4 days it has dropped to 11V and the MH requires a jump start.
Can I ask is the voltage drop irrefutable evidence that the battery is knackered?
I ask this question because I'm taking it back to the dealer who wants to run a 24 hour test on the battery before agreeing (hopefully) to renew it and I don't want to be fobbed off by some inappropriate statement!
Thanks again in anticipation
Ian
With engine running the voltage at the starter battery terminals should be over 14 volts (around 14.2 to 14.5). Any less than 14v and the battery is not being charged. Have the alternator checked and the battery fully charged off the vehicle then try again.
 
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IanF
May 7, 2013
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On our 2nd MH now a AutoTrail Savannah which we're absolutely delighted with
With engine running the voltage at the starter battery terminals should be over 14 volts (around 14.2 to 14.5). Any less than 14v and the battery is not being charged. Have the alternator checked and the battery fully charged off the vehicle then try again.
Thanks for that advice -I've never actually checked the voltage with the engine running. I've checked it within minutes of stopping and get results in the upper 13 Vs
Ian

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Charlie

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Thanks Pappajohn but I do hope to get Marquis to replace it for me as I don't think you can say it's fit for purpose if you have a MH which can't motor without a jump start every 4 days or so

Have you done a drain test ? Often called a parasitic draw ?

If you have a simple voltage meter it's not hard to do.

If it's of interest I will find a YouTube link to a video which will explain it better than I can .

If your battery is over 13 after a drive I would say your alternator is working fine. If it drops after that it's likely you have a draw on it.
 
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Aug 9, 2015
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Not sure if you have solved your problem yet but I had a similar problem, I suspected the battery would not hold it's charge and took it back to the dealer. They checked the vehicle and found the fault was a drain from an incorrectly wired reversing camera. They rewired it and it has been fine since. My advice is to take it back to your dealer and have the system checked.

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Apr 7, 2021
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Hi Everyone, going to use this thread as it's very similar to an issue we have and that video looks very useful so will also follow that. We have a 2010 Ducato x250 2.3l under an Autotrail Mohawk. Last week I replaced the starter battery as the previous battery was kaput, so dead nothing came on with a key turn. I bought a Yuasa Silver High Performance Car Battery 12V 100Ah HSB019 and prior to installing it was on a maintenance charge at ~13.8v. The battery went in, vehicle started, all was well in the world.

I went back to the van today and checked the EC325 panel, the engine battery was at 9.8v (Poor), a week later. The van is in covered storage so I would expect a slight drop, but not that much. Luckily, the van started and I have brought it home, put the leisure batteries back in and plugged it into the house. At the end of the month I am taking the van to Vanbitz for a Battery Master and Sterling B2B 1260 Charger but Ian has rightly asked that I try and resolve the engine battery issue first. I can imagine that while there is an issue with parasitic drain, fitting the Battery Master will just drain the leisure batteries very quickly. I hope the engine battery isn't toast now as well after dropping to 9.8v. I'll have to perhaps disconnect it and do a drain test also to see if it can still hold a charge, or just check the control panel and the battery voltage.

The question I had was does the battery current reading on the EC325 panel act as an ammeter? At rest on the driveway with nothing turned on and the doors shut the draw on the engine battery showed 12.7A which to me seems huge. On the leisure batteries it was 16.4A, this really doesn't seem right to me.

So, I am going to buy a multi-meter and follow that video. I'm no electrician so embarking on a massive learning curve.

Thanks

David

IMG_2648.JPG
IMG_2647.JPG
 
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Feb 9, 2008
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I too have a 2011 Autotrail. With both sets of batteries fully charged and everything switched off I would see a drain of about 0.2 Amps. The drain you have showing on both sets of batteries is amazingly high and to be honest the only device I would expect to see with this sort of drain would be your Fridge/Freezer. I would suggest you start pulling fuses one at a time from your P.S.U. as this may identify the circuit where the drain is occurring. In the short term, Disconnect your cab battery neg connection after fully charging your battery, if keeping in storage to prevent further drain on your cab battery.
 
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Oct 10, 2018
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davida71uk I believe that the the EC325 may need to be re-calibrated when the battery is replaced , the Sargent electrical web site has the information on how to do this in their Support section in Control panels manuals. It may be that your control panel is giving wrong information as I would not expect a battery with 9.8v in it to start the Motor home so hopefully it may just be that re-calibration of the control panel is required.

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Feb 9, 2008
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davida71uk I believe that the the EC325 needs to be re-calibrated when the battery is replaced , the Sargent electrical web site has the information on how to do this in their Support section in Control panels manuals. It may be that your control panel is giving wrong information as I would not expect a battery with 9.8v in it to start the Motor home so hopefully it may just be that re-calibration of the control panel is required.
I have never needed to do this when replacing batteries but agree starting the engine with 9.8V does not add up. If you have a volt meter (Cheap as chips) you can check reading at battery and compare with control panel to establish if there is an error.
 
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Apr 7, 2021
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Thanks GeoffnDee will check that out. UNI-T UT210E ordered also.

Re-calibrate the current sensor as follows:
With the charger switch turned off, and the power turned off at the
control panel (no LED’s on)
Scroll down ▼ the display until battery current is shown
Hold down the select button ◄ (left arrow) until 'calibrating….'
appears; keep the button pressed until the battery current reading reappears.
Release the button.
Now repeat the process to store the new setting.
Hold down the select button ◄ (left arrow) until 'calibrating….'
appears; keep the button pressed until the battery current reading reappears.
The current reading should now be correct
 
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Apr 7, 2021
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Dont forget You also need to disconnect the solar panel at the PSU or carry out the calibration at night. (Sargent manual) , I suppose you could also cover the solar panel if doing this daytime, to save having to disconnect it.
It was very dark 👍
 
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pappajohn

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went back to the van today and checked the EC325 panel, the engine battery was at 9.8v (Poor), a week later. The van is in covered storage so I would expect a slight drop, but not that much. Luckily, the van started and I have brought it hom
If the van cranked and started at 9.8v the panel/meter is at fault and not the battery.
At 9.8v the voltage indicates the battery is fully dead and probably wouldn't even light the dashboard lights

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Apr 7, 2021
201
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Solihull, UK
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If the van cranked and started at 9.8v the panel/meter is at fault and not the battery.
At 9.8v the voltage indicates the battery is fully dead and probably wouldn't even light the dashboard lights
Have recalibrated the panel but it’s not clear if this is a discharge reading reset and also a battery voltage reading meter reset. Once I get a multimeter I will check the drain on it. I too was surprised the engine cranked and started this morning.
 
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Apr 27, 2016
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UNI-T UT210E ordered also.
That's a great call. For others reading this thread, it's a clamp meter that measures DC amps by clipping around the wire and sensing the magnetic field the amps generates. No disconnection and connection required.

Note that in the video he mentions 'luxury vehicles' with extra electrics, computer chips in everything, and communication between the parts. This technology is now pretty much mainstream, in most vehicles. The advantage of a clamp meter is you can measure without disturbing anything. You can tell if a control unit is not going into 'sleep mode', for example.

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Apr 7, 2021
201
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Solihull, UK
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I think I may even have a Victron ammeter put in the dash on leisure and engine (if it can do both) to take away the EC325 control panel guesswork.
 
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Jan 28, 2008
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If in doubt just replace it.
If, as you say, it has a BM fitted and solar your battery is cabbaged.

An engine battery will cost around £60 at a guess.
how do you comw to that conclusion without knowing if there is a draw on the battery?could be a cupboard light or similar left onm? it needs the draw checking to be sure
 
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