Flat battery horn going off

[Nigel Coleman]

I did loads of research before buying my NOCO and came to the conclusion that ANY brand of jump start pack 1000 amps or less may not be good enough for a V8 engine as in the SC430.

I finally choose the 1250 amp NOCO GBX45 which is a little more costly BUT REALY DOES THE JOB!

I'm 100% satisfied with it and would recommend it to anyone.

[Boomer54]

Completed the setup on the Battery monitor this morning. Just in time ! Now charging up and the BM2 App appears to be working seamlessly at least on test mode and cranking mode. Have not yet tried out trip mode, but I think that might be useful if you do short journeys and also use say the audio system regularly. Pile on top of that lights etc in winter. Easy to see how depletion on those trip might offset any charge accrued on the trip. Yes, I think big thanks to the guys above pointing in this direction. I am going to be more assured in the months ahead as to what is going on with the Battery system and of course the Alternator.

[Glyn Jennings]

On 10/15/2023 at 7:48 PM, Glyn Jennings said:

I’ve just bought one of these so hopefully now I can keep an eye on battery charge level. I don’t expect it to be 100% accurate but it’s better than nothing.

https://www.amazon.co.uk/Battery-Monitor-Campervans-Compatible-bluetooth/dp/B08VHMJYXY
 

So I fitted the BM2 Battery monitor yesterday afternoon on the new Battery and it was reading 100% charge (SOV) and 12.71v. I have not driven the car and this morning it says 87% charge (SOV) and 12.53v.  So it seems to me as I have read in some reviews the BM2 SOV estimates are way off.  I have read that a daily drop in charge for a car Battery is normally 1 - 1.5% drop depending on outside temperature so if my calculations are correct the drop in voltage of 0.18v (1.4%) for one day is about right considering I have a tracker fitted as well and the BM2. Is this about what others have experienced?

[Boomer54]

6 minutes ago, Glyn Jennings said:

So I fitted the BM2 battery monitor yesterday afternoon on the new battery and it was reading 100% charge (SOV) and 12.71v. I have not driven the car and this morning it says 87% charge (SOV) and 12.53v.  So it seems to me as I have read in some reviews the BM2 SOV estimates are way off.  I have read that a daily drop in charge for a car battery is normally 1 - 1.5% drop depending on outside temperature so if my calculations are correct the drop in voltage of 0.18v (1.4%) for one day is about right considering I have a tracker fitted as well and the BM2. Is this about what others have experienced?

Too early for me to tell ,but I will let you know tomorrow ,or the day after. At end of today the Battery should be fully charged so I will have something to measure against. I hope it is not wildly inaccurate ,because I will probably return it if it is and look for an alternative.

[Boomer54]

22 hours ago, Boomer54 said:

Too early for me to tell ,but I will let you know tomorrow ,or the day after. At end of today the battery should be fully charged so I will have something to measure against. I hope it is not wildly inaccurate ,because I will probably return it if it is and look for an alternative.

Put the tester on this morning. Gone from 100% fully charged last night to 55%charge this morning. Voltage virtually unchanged to a decimal point. New territory for me so it's unclear what is going on. Do I, have a Battery that is losing charge rapidly (which would not be good), or is this Battery monitor tester wildly inaccurate? How do I tell? I guess the answer is if a user has a relatively new Battery that is being monitored and it is also displaying those kind of discharge stats then the tester is the likely culprit. What do we think if we think anything conclusive about this at all?

[Nigel Coleman]

The alarm/immobiliser - if set - will drain a certain amount of the Battery overnight.

As a test you could disable the alarm overnight (lock the passenger door from inside then lock the drivers door with the key) and see if the Battery drainage is still the same in the morning.

[Boomer54]

5 minutes ago, Nigel Coleman said:

The alarm/immobiliser - if set - will drain a certain amount of the battery overnight.

As a test you could disable the alarm overnight (lock the passenger door from inside then lock the drivers door with the key) and see if the battery drainage is still the same in the morning.

That's certainly a consideration and something to tweak, but do we think that an immobiieser could make such a massive difference overnight. based on the overnight drop reading then in two or three days this Battery would be fully discharged. Now I already know that is not the case just by virtue of how it's been driven since I bought it at start of Sept'. 

I will recharge to full and do what you suggest to see what change in readings I get. I just think there might be more to this story.

[Boomer54]

Mysterious indeed. Just cam eback from a short run that would not really help charge. For interest I put the tester on and whereas the reading early today was 55% ,it had now risen to 88%. As I say the drive was far too short to make any impact so I am at a loss to explain  this change. A drop from the 100% yesterday to 88% charge today is probably still a bit heavy, but nowhere near as drastic as the 55% read earlier today.

Anyway put it back on charge with a view to get 100% charge today. Then I will disable  the alarm and read it again tomorrow morning. I will play with this for a few days and see if any pattern emerges before I decide what to do with this tester.

[Glyn Jennings]

2 hours ago, Boomer54 said:

Mysterious indeed. Just cam eback from a short run that would not really help charge. For interest I put the tester on and whereas the reading early today was 55% ,it had now risen to 88%. As I say the drive was far too short to make any impact so I am at a loss to explain  this change. A drop from the 100% yesterday to 88% charge today is probably still a bit heavy, but nowhere near as drastic as the 55% read earlier today.

Anyway put it back on charge with a view to get 100% charge today. Then I will disable  the alarm and read it again tomorrow morning. I will play with this for a few days and see if any pattern emerges before I decide what to do with this tester.

I don't think you can rely on the percentage charge (SOV) on any of the Battery monitors to be accurate.  Mine was !00% Monday, 87% yesterday and 67% today. The Battery charge voltage level has been 12.71v, 12.53v and 12.41v which i the expected drop of roughly 1% voltage drop per day.  The state of charge for a Battery drops dramatically compared to voltage drop. 12.7v is 100% 12.32v is 70% and 12.03v is 50% according to what I have seen on line. If it drops below 10.5 V the Battery will be ruined as it will have no charge at all and won't be able to be revived.

[Illogan]

On 10/16/2023 at 11:05 PM, Nigel Coleman said:

I did loads of research before buying my NOCO and came to the conclusion that ANY brand of jump start pack 1000 amps or less may not be good enough for a V8 engine as in the SC430.

I finally choose the 1250 amp NOCO GBX45 which is a little more costly BUT REALY DOES THE JOB! (

I'm 100% satisfied with it and would recommend it to anyone.

I bought a NOCO Boost HS GB70 2000A  (initially for our (now deceased) MBenz S500), but it's a superb piece of kit, and is often borrowed by neighbours, (and is useful for our boat, too)

Just SO useful

[Boomer54]

1 hour ago, Illogan said:

I bought a NOCO Boost HS GB70 2000A  (initially for our (now deceased) MBenz S500), but it's a superb piece of kit, and is often borrowed by neighbours, (and is useful for our boat, too)

Just SO useful

After reading this link I realise that strange as it may seem to the reader the problem I am getting is once again attributable to the idiot in charge of the car.

Car Battery Voltage Chart UK - Car Battery Geek

All my mysterious readings are not so mysterious so much as I don't know what I am doing. Anyway, all is clear. Nothing wrong with my Battery. Nothing much wrong with the Battery monitor other than to understand what it can do well and what is to be ignored. I will keep the monitor because all it needs to do is accurately tell me what the voltage is and from that I can estimate depletion and know if it needs charging up. Job done, out, going to comfort eat a donut whilst gently banging my head against a very hard surface.

[Glyn Jennings]

So my new Battery has now been on the car 7 days and not been driven and the normal predicted 1-1.5v % drop per day is evident so the Battery drain on the car is normal. It started at 12.7v and today is 12.2v according to the Battery monitor. However the SOC estimate is miles out as you can see in the attached photo. At 12.2v it should read 60% charge and not 31%. I guess this means I am going to need to connect the CTEK maintenance charger every week rather than every 2 to 3 weeks I had been doing to prolong the life of the new Battery. This is a pain as I have to run an extension lead from an outside wall socket and put it under a cable cover across the pavement. I will have a look now to see if you can get perhaps a lithium Battery charger that you can keep charged indoors and just connect to the car Battery without all the cabling necessary with the CTEK.

[Boomer54]

Your results are comparable with mine albeit over a slightly shorter time period. The SOC is basically useless, but the voltage charge is enough for the purpose required.

[Glyn Jennings]

Anyone use one of these?

https://www.amazon.co.uk/OptiMate-Automatic-Battery-Optimiser-Maintainer/dp/B07L3MPCVL/ref=mp_s_a_1_1?crid=D3EOMFI5BDPK&keywords=optimate+40w+solar&qid=1698682309&sprefix=otimate+40w+solar%2Caps%2C87&sr=8-1

Seems to get good reviews whereas the cheap ones get generally poor reviews. You can even buy a separate adapter to plug it in to th OBD port.

[Boomer54]

1 hour ago, Glyn Jennings said:

Anyone use one of these?

https://www.amazon.co.uk/OptiMate-Automatic-Battery-Optimiser-Maintainer/dp/B07L3MPCVL/ref=mp_s_a_1_1?crid=D3EOMFI5BDPK&keywords=optimate+40w+solar&qid=1698682309&sprefix=otimate+40w+solar%2Caps%2C87&sr=8-1

Seems to get good reviews whereas the cheap ones get generally poor reviews. You can even buy a separate adapter to plug it in to th OBD port.

So now I know what a OBD port is and what it does. Not anywhere close to the wharp drive afterall.

[Glyn Jennings]

I thought I would just update this thread where I currently am with this  issue. I bought an Optimate 40w duo solar panel which I placed inside against windscreen and connected to the Battery via a cable to the OBD port as one of the pins is a permanent live and another an earth to the Battery. After being fitted now for just over two weeks I can conclude although slowing the Battery discharge rate down it is insufficient to keep the Battery fully charged. Disappointing as I went for the bigger panel thinking it would be OK. Obviously the windscreen tint, being inside plus the panel facing east so only getting sun for half the day is not enough exposure. So my latest plan has been to purchase and fix the optional sucker pads to the panel and now mount it outside on the roof.  Hopefully now with the panel now fully exposed to the sun whenever it is out and for how long it will be enough to maintain the Battery level.  Fortunately i was able to return the OBD connecting cable for a refund. Having  driven the car last week there is no doubt that if you can drive the car for half an hour a week that is enough to keep the Battery sufficiently charged.

On another note which I don’t think has helped the issue is the Aldi GPS tracker I had fitted with the plastic bag you get to put it in to keep it waterproof was completely full of water. I had it permanently connected to Battery to keep it charged which meant you couldn’t fully seal the bag because of the cable to recharge it. I suspect that although small a permanent current would have be drawing rather that that just activated by the motion sensor. The tracker is now completely trashed but it may not be such a great loss as it worked on the 2G network and a lot of providers are phasing it out. The latest now pricier new trackers now work on 4G and only need to be recharged every 120 days so no longer need to be connected to the Battery for convenience.

[Boomer54]

1 hour ago, Glyn Jennings said:

I thought I would just update this thread where I currently am with this  issue. I bought an Optimate 40w duo solar panel which I placed inside against windscreen and connected to the battery via a cable to the OBD port as one of the pins is a permanent live and another an earth to the battery. After being fitted now for just over two weeks I can conclude although slowing the battery discharge rate down it is insufficient to keep the battery fully charged. Disappointing as I went for the bigger panel thinking it would be OK. Obviously the windscreen tint, being inside plus the panel facing east so only getting sun for half the day is not enough exposure. So my latest plan has been to purchase and fix the optional sucker pads to the panel and now mount it outside on the roof.  Hopefully now with the panel now fully exposed to the sun whenever it is out and for how long it will be enough to maintain the battery level.  Fortunately i was able to return the OBD connecting cable for a refund. Having  driven the car last week there is no doubt that if you can drive the car for half an hour a week that is enough to keep the battery sufficiently charged.

On another note which I don’t think has helped the issue is the Aldi GPS tracker I had fitted with the plastic bag you get to put it in to keep it waterproof was completely full of water. I had it permanently connected to battery to keep it charged which meant you couldn’t fully seal the bag because of the cable to recharge it. I suspect that although small a permanent current would have be drawing rather that that just activated by the motion sensor. The tracker is now completely trashed but it may not be such a great loss as it worked on the 2G network and a lot of providers are phasing it out. The latest now pricier new trackers now work on 4G and only need to be recharged every 120 days so no longer need to be connected to the battery for convenience.

Cannot get a spell between rain to get my new Battery fitted. Mind you I got it home and went to put it into my log store to keep it dry. Lifted my flaps on the store placing my cobble weights that hold the flap down on top of the store. Duly caught the flaps putting the Battery away and got smacked on the head by the granite cobble I accidentally pulled off. All I will say is do not play head the cobble, it hurts.

[Glyn Jennings]

On 11/19/2023 at 3:36 PM, Glyn Jennings said:

I thought I would just update this thread where I currently am with this  issue. I bought an Optimate 40w duo solar panel which I placed inside against windscreen and connected to the battery via a cable to the OBD port as one of the pins is a permanent live and another an earth to the battery. After being fitted now for just over two weeks I can conclude although slowing the battery discharge rate down it is insufficient to keep the battery fully charged. Disappointing as I went for the bigger panel thinking it would be OK. Obviously the windscreen tint, being inside plus the panel facing east so only getting sun for half the day is not enough exposure. So my latest plan has been to purchase and fix the optional sucker pads to the panel and now mount it outside on the roof.  Hopefully now with the panel now fully exposed to the sun whenever it is out and for how long it will be enough to maintain the battery level.  Fortunately i was able to return the OBD connecting cable for a refund. Having  driven the car last week there is no doubt that if you can drive the car for half an hour a week that is enough to keep the battery sufficiently charged.

On another note which I don’t think has helped the issue is the Aldi GPS tracker I had fitted with the plastic bag you get to put it in to keep it waterproof was completely full of water. I had it permanently connected to battery to keep it charged which meant you couldn’t fully seal the bag because of the cable to recharge it. I suspect that although small a permanent current would have be drawing rather that that just activated by the motion sensor. The tracker is now completely trashed but it may not be such a great loss as it worked on the 2G network and a lot of providers are phasing it out. The latest now pricier new trackers now work on 4G and only need to be recharged every 120 days so no longer need to be connected to the battery for convenience.

Just another quick update. The solar panel despite being now on the top of the roof was not enough to maintain a fully charged Battery during the winter months. Now the days are longer it does now seem to be able to keep the Battery fully charged. I have also now purchased a tracker with its own rechargeable Battery so no additional drain now. Hopefully I won’t have any further issues.

[Boomer54]

10 minutes ago, Glyn Jennings said:

Just another quick update. The solar panel despite being now on the top of the roof was not enough to maintain a fully charged battery during the winter months. Now the days are longer it does now seem to be able to keep the battery fully charged. I have also now purchased a tracker with its own rechargeable battery so no additional drain now. Hopefully I won’t have any further issues.

That's interesting and useful. Thanks Glyn.

[Glyn Jennings]

19 minutes ago, Glyn Jennings said:

Just another quick update. The solar panel despite being now on the top of the roof was not enough to maintain a fully charged battery during the winter months. Now the days are longer it does now seem to be able to keep the battery fully charged. I have also now purchased a tracker with its own rechargeable battery so no additional drain now. Hopefully I won’t have any further issues.

I forgot to mention the blue tooth Battery monitor I fitted in October stopped working and there was no way of sending it back or getting a refund via amazon. Well cheesed off I left a negative review. I then thought I would just check it with a multimeter and I got a resistance reading so put it back on the car and it started working again.

[lawler999]

Had no problems with my Battery since I fitted the remote Battery isolator , will do some more investigation when the weather gets better as to where my drain could be coming from , but it's nice to know I can leave it for months if I want and it will start when needed .