Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 3rd June 2020, 16:43   #21
Supervinnie40
I really should get out more.......
 
Supervinnie40's Avatar
 
Rover 75 1.8 Club

Join Date: Dec 2013
Location: Tilburg (Netherland)
Posts: 2,612
Thanks: 572
Thanked 336 Times in 247 Posts
Default

Thanks, I don't have a highline system or satnav. Also no CD player either. Only a Navall Android unit, which I've already checked
__________________
Proud owner of the Dutch "Golden 75". A much loved Gold White Metallic Rover 75 1.8 na from 2000.
Supervinnie40 is offline   Reply With Quote
Old 3rd June 2020, 18:39   #22
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,263
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

Hello Vinnie,

Sorry, my suggestion hasn't worked. I see from your photograph that you cannot hot-switch from the 10 amp range to the 200mA range because you need to move the red probe to a different socket.

You could try locking the car to create realistic circumstances.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Old 4th June 2020, 04:36   #23
Supervinnie40
I really should get out more.......
 
Supervinnie40's Avatar
 
Rover 75 1.8 Club

Join Date: Dec 2013
Location: Tilburg (Netherland)
Posts: 2,612
Thanks: 572
Thanked 336 Times in 247 Posts
Default

Actually, I think I can hot-switch. Before the photo, the multimeter was set to 10a. I only turned the dial to 200ma. I didn't switch over the probes. It still gave me the same value. So it seems to work.
__________________
Proud owner of the Dutch "Golden 75". A much loved Gold White Metallic Rover 75 1.8 na from 2000.
Supervinnie40 is offline   Reply With Quote
Old 4th June 2020, 15:25   #24
Supervinnie40
I really should get out more.......
 
Supervinnie40's Avatar
 
Rover 75 1.8 Club

Join Date: Dec 2013
Location: Tilburg (Netherland)
Posts: 2,612
Thanks: 572
Thanked 336 Times in 247 Posts
Default

My nieghbour pointed out to me that some batteries can drain by themselves. Although I heard this before, I didn't take it into account in my tests.

So, I charged the battery yesterday, and have left it alone for at least 24 hours.
When I disconnected the charger yesterday, it said 12.45 volt.
I just went out to check, and the battery now gives 12.29 volt.
In the last 24 hours it has dropped 0.16 volts.

In the past (before it got worse) I had a flat battery after roughly 1 week of not driving. This would mean that the battery could've lost roughly (0.16 * 7) 1.12 volts. That would give me roughly 11.33 volts to start with.
Would that be an issue? Would that give me problems starting? (honestly don't know).

Add to the whole story a drainage of a minimum of 0.07 amps, and I might be in trouble? The thing I haven't been able to figure out, is what can be expected as a regular drain? I've read articles that say 0.04 is normal, and other say it can go as high as 0.1 amps with certain models.

I'm gonna leave the battery disconnected for another 24 hours. Then I'm gonna do some more testing with the fuses.
__________________
Proud owner of the Dutch "Golden 75". A much loved Gold White Metallic Rover 75 1.8 na from 2000.
Supervinnie40 is offline   Reply With Quote
Old 4th June 2020, 16:04   #25
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,263
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

Quote:
Originally Posted by Supervinnie40 View Post
The thing I haven't been able to figure out, is what can be expected as a regular drain?
I gave you the official MGR version in post no. 16 Vinnie.
Quote:
Originally Posted by Supervinnie40 View Post
... I charged the battery yesterday, and have left it alone for at least 24 hours. When I disconnected the charger yesterday, it said 12.45 volt.
It's normal for the voltage to be temporarily high for a period immediately after charging.

Vinnie, do you normally do a lot of short journeys or is the car left unused for long periods?
Quote:
Originally Posted by Supervinnie40 View Post
In the past (before it got worse) I had a flat battery after roughly 1 week of not driving.
That suggests that your battery was either in need of external charging or it had already passed the point of no return. It happens to us all. Despite taking precautions during the lockdown, I ended up with a flat battery.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.

Last edited by SD1too; 4th June 2020 at 16:06..
SD1too is offline   Reply With Quote
Old 4th June 2020, 17:29   #26
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 14,003
Thanks: 3,851
Thanked 2,167 Times in 1,816 Posts
Default

1/ How old is your battery ?

2/ How long do you charge it for when you say--I've charged the battery---?

3/ Your car will not start on a battery voltage of 11.33 volts.

4/ All batteries slowly discharge by themselves. From full to just about flat can take six months or more though.

5/ As a battery in use discharges, the current flows from Negative to Positive terminals.---
COLVERT is offline   Reply With Quote
Old 4th June 2020, 18:17   #27
Supervinnie40
I really should get out more.......
 
Supervinnie40's Avatar
 
Rover 75 1.8 Club

Join Date: Dec 2013
Location: Tilburg (Netherland)
Posts: 2,612
Thanks: 572
Thanked 336 Times in 247 Posts
Default

Quote:
Originally Posted by SD1too View Post
I gave you the official MGR version in post no. 16 Vinnie.
Sorry, I forgot that when I was typing my text. Was getting slightly upset with not being able to find the problem.
It's normal for the voltage to be temporarily high for a period immediately after charging.
Fair enough. So the discharge could be lower then I thought. we'll see what it says tomorrow. Should give a more honest representation.

Vinnie, do you normally do a lot of short journeys or is the car left unused for long periods?
Normally not, but with the semi-lockdown in Holland I either left it standing still for a week easily, and did a few short drives (about 15km, parking and driving back 15km after an hour)

That suggests that your battery was either in need of external charging or it had already passed the point of no return. It happens to us all. Despite taking precautions during the lockdown, I ended up with a flat battery.
To be honest, it happened twice that my battery was below 6v. Some sources say the battery is scrap after this. Weirdly enough, this happened after only 1.5 weeks after parking the car. I did several longer runs (40km) before that time.

Simon
Quote:
Originally Posted by COLVERT View Post
1/ How old is your battery ?
This one is about 8 months old. Replaced it after the previous one also drained and wouldn't charge back up properly anymore.

2/ How long do you charge it for when you say--I've charged the battery---?
My battery charger stops automatically and goes into trickel-charge after that. I only disconnect the charger after I saw the trickle-charge light come on.

3/ Your car will not start on a battery voltage of 11.33 volts.
Thanks for that info. That is not a good sign if my battery really does discharge on its own

4/ All batteries slowly discharge by themselves. From full to just about flat can take six months or more though.
In my case it only took 1 week to go down to 6v after parking the car after regular use.

5/ As a battery in use discharges, the current flows from Negative to Positive terminals.---
I measured a few times between the + lead and the - lead. I got the same readings. I have been told that it doesn't really matter, you only need to be careful not to touch the body with the + lead.
I'll retry to measure the voltage tomorrow. That should give a better indication on the discharge.
I do remember the car starting and driving pretty much fine before. After parking the car (after regular use) the battery drained within 1.5 week, and started to go empty more quickly. The last time, it took 2 or 3 days to go empty enough to not start the car anymore (and this was after a full charge).
__________________
Proud owner of the Dutch "Golden 75". A much loved Gold White Metallic Rover 75 1.8 na from 2000.
Supervinnie40 is offline   Reply With Quote
Old 4th June 2020, 19:20   #28
edwardmk
Gets stuck in
 
edwardmk's Avatar
 
MG ZT 260, Rover 75 Connie SE auto

Join Date: Feb 2013
Location: Redruth
Posts: 982
Thanks: 1,324
Thanked 399 Times in 271 Posts
Default

Quote:
Originally Posted by Supervinnie40 View Post
Thanks for the confirmation. I'll continue testing with not switching the pins around.


I check these weekly, but never hurts to check once again. They are bone dry and all plenums are clear. I can see the pavement under the car. Ecu looks a bit dusty at most, but pretty clean and dry. No signs of moisture or waterlines on the cabin filter either.


Unfortunately, the car has made me scratch my head once again. Really confused now!

I realized I never tried what happens when I simply leave the multimeter attached. Not disconnect it all the time. So I got a few clamps and attached the multimeter as above, and left it in place.

First sign (with the 5 fuses mentioned above removed, I saw that the current goes up when the doors have been opened. When I close the doors, the current drops after roughly 1 minute down to 0.06 amp.

I then saw I didn't connect the alternator (took it off last night). So I put that back, and openen a few doors. Amp went up at first, but dropped after a minute to 0.07 amp.

Finally, I put all 5 fuses back and connected everything in the car as normal. At first the amp went up (just opened a door), but eventually it dropped again down to 0.08 and stayed there.

So, with the multimeter connected (and not pulling it loose all the time), the amps go down as can be expected. (0.08 is reasonable I think?)
But if I disconnect the leads, and reconnect them, the amps go up to 0.3 amps, without touching the doors.

I'm starting to loose the plot haha.
I had the same problems with my 260 last year. Like you I took many readings and swapped around every fuse I could find. Because my battery was fairly young ( around 10-11 months I seem to recollect) I assumed it was OK. I invested in various pieces of test kit but got mixed results. Finally I gave up and went back to Halfords who were initially doubtful it could be faulty (fairly new battery). Their service guy appeared with a very expensive meter which gave a simple message...'replace battery'. Then they were as good as gold and exchanged it under their 4 year warranty. All my issues disappeared. I now hook up a Ctek 5a charger when it isn't in use for more than a week and it now starts first time (so far lol). Apparently batteries which are fairly new can lose a cell and cause trouble, especially if the battery has been run very flat. SD1 and Colvert were both very helpful at that time too. And it is technically correct that electrons travel from negative to positive.
edwardmk is offline   Reply With Quote
Old 4th June 2020, 19:46   #29
vitesse
I really should get out more.......
 
Rover 75 Saloon

Join Date: Jul 2011
Location: Gävle
Posts: 2,515
Thanks: 395
Thanked 823 Times in 652 Posts
Default

Your post prompted me to have a look at two of my spare batteries in the garage. I probably last charged them about 2 or 3 months ago on a standard (non-clever) charger. At the time my son-in-law had problems starting but it always started with a freshly charged battery and then eventually wouldn't start at all. But it was the starter solenoid at fault so I kept the batteries charged until I replaced the solenoid which was probably in April. They haven't been charged since.
The Bosch battery read 12.7v / the Tudor just over 13v.

Regards
vitesse is offline   Reply With Quote
Old 4th June 2020, 20:17   #30
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 14,003
Thanks: 3,851
Thanked 2,167 Times in 1,816 Posts
Default

Vinnie.

Item 2/ in my post.

The fact that your charger goes into TRICKLE mode does not, unfortunately, mean your battery is fully charged.

All that charger is telling you is that the part of your battery that is healthy enough to take a charge has been charged.

If your battery is almost at the end of its useful life and the plates are beginning to fail that charger just says---I've done my best with what's left of your battery plates. The resistance they put up when I'm tying to charge them says to me they are fully charged so I relay that message to you. BUT it's very rarely true.---

You could be fighting a losing battle with a battery that's on its last gasp.

Nowadays when the acid in a battery can't be got at to test it the best remaining way is with a garage Drop-Tester.--
COLVERT is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 11:29.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd