Battery drain

Shide · 30th September 2018, 21:35

Have been suffering from an inexplicable trickle drain to my battery. Leave the car for four or five days and the battery would be flat enough to slide it under the door. Have heard about the car 'not going to sleep properly' when locked but I just had a thought about something else. I forced son No2 into the boot and shut him in, and yes, the boot light stayed on. Anyone else had/cured this problem?
PS. I did let him out again.

Shide · 30th September 2018, 21:39

PPS. Pulled a wire off to avoid repetition.

Mike Noc · 1st October 2018, 07:03

The boot light should go out after around 15 minutes Carl, even if you leave the boot lid open - easy enough to plug the wire back in and check that it does.

Have you tried a spare battery?

raykay · 1st October 2018, 08:46

The boot light is on the same circuit as the interior lights and should operate with them in automatic mode when a door/boot is opened.

Shide · 1st October 2018, 09:56

Didn't know that. I thought it would simply go on and off when the boot is opened and closed. I'll try leaving it open to see if it does go out after 15 mins. Almost certain I don't have a dud battery. I have been using the simple expedient of disconnecting the battery overnight to alleviate the problem.

raykay · 1st October 2018, 10:04

If the interior lights go on and off when you open and close a door or boot, so will the boot light.

Have you got a navigation system? They have been known to cause that problem.

Bullnose75 · 1st October 2018, 12:25

I had a flat battery the other morning in my Tourer,11.7 volts. Starter wouldn't turn engine over. Battery is only five months old. Recharged it,put it back on car,checked nothing was left on,lights etc. Flat again next morning 11. 7 volts ish again.
Checked for battery drain yesterday with multimeter - showed fluctuating reading between 3.38 amp and 2,75 amp drain with nothing on apart from clock. Only thing i'd fitted recently was a replacement CD changer(which only works when it feels like it) so unplugged that and battery drain went down to a steady 2.5amp,still too high a drain but that pointed me in the right direction. Removed fuse 33 (the radio,audio one) and battery drain went back to a normal less than half an amp drain (.43 actually).
When I got the Tourer back in April the radio didn't work until I found the rocker switch someone had fitted under the steering column. Used car like that for a while,turning power to radio on and off with the rocker switch. Tried it without rocker switch and the radio fuse 33 back in and radio has worked fine for months until now. Looking through previous owners pile of bills for parts etc that he'd had fitted to car over the years did show that he'd been fitting brand new batteries every couple of years or so,proper good brand ones not cheapos,so guess he'd been having intermittent flat batteries too until someone sourced the fault to the factory fitted radio.
So might be worth you removing fuse 33 to see if prob is radio related on yours too

Shide · 10th October 2018, 10:31

I deliberately left the car unused for five days to see if the battery had gone flat again. Started first time whereas before there would be nothing. Safe to assume then that the problem lay in the boot light not going out.

Mike Noc · 10th October 2018, 10:54

Did you leave the boot open and see if the light went out after 15 minutes or so as it should?

If it does stay on continuously then it could well be your fault, but these battery drains can come and go, especially if related to water ingress where the car gets soaked one week and dries out the next.

Shide · 4th April 2019, 21:17

I think I have sussed out the battery 'leak'. The problem appears to be the alternator. Unplugged the multi-pin plug at the rear and left it for a few days. Plugged it back in and she fired up with no problem. If I had left it for the same time 'plugged in' the battery would be flat. So, why would the power drain out through the alternator?

30th September 2018, 21:35	#1
Shide Avid contributor Rover 75 1.8T Join Date: Jun 2015 Location: Ash Vale Posts: 133 Thanks: 5 Thanked 13 Times in 10 Posts	Battery drain Have been suffering from an inexplicable trickle drain to my battery. Leave the car for four or five days and the battery would be flat enough to slide it under the door. Have heard about the car 'not going to sleep properly' when locked but I just had a thought about something else. I forced son No2 into the boot and shut him in, and yes, the boot light stayed on. Anyone else had/cured this problem? PS. I did let him out again.

1st October 2018, 09:56	#5
Shide Avid contributor Rover 75 1.8T Join Date: Jun 2015 Location: Ash Vale Posts: 133 Thanks: 5 Thanked 13 Times in 10 Posts	Re light Didn't know that. I thought it would simply go on and off when the boot is opened and closed. I'll try leaving it open to see if it does go out after 15 mins. Almost certain I don't have a dud battery. I have been using the simple expedient of disconnecting the battery overnight to alleviate the problem.

1st October 2018, 10:04	#6
raykay I really should get out more....... Now Other Manufacturer Join Date: Nov 2006 Location: Co. Kerry Posts: 2,786 Thanks: 16 Thanked 310 Times in 283 Posts	If the interior lights go on and off when you open and close a door or boot, so will the boot light. Have you got a navigation system? They have been known to cause that problem. Last edited by raykay; 1st October 2018 at 11:20..

10th October 2018, 10:31	#8
Shide Avid contributor Rover 75 1.8T Join Date: Jun 2015 Location: Ash Vale Posts: 133 Thanks: 5 Thanked 13 Times in 10 Posts	battery drain update I deliberately left the car unused for five days to see if the battery had gone flat again. Started first time whereas before there would be nothing. Safe to assume then that the problem lay in the boot light not going out.

30th September 2018, 21:39	#2
Shide Avid contributor Rover 75 1.8T Join Date: Jun 2015 Location: Ash Vale Posts: 133 Thanks: 5 Thanked 13 Times in 10 Posts	PPS. Pulled a wire off to avoid repetition.

1st October 2018, 07:03	#3
Mike Noc This is my second home Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4. Join Date: Jul 2009 Location: Hampshire Posts: 11,550 Thanks: 3,470 Thanked 3,119 Times in 2,247 Posts	The boot light should go out after around 15 minutes Carl, even if you leave the boot lid open - easy enough to plug the wire back in and check that it does. Have you tried a spare battery?

1st October 2018, 08:46	#4
raykay I really should get out more....... Now Other Manufacturer Join Date: Nov 2006 Location: Co. Kerry Posts: 2,786 Thanks: 16 Thanked 310 Times in 283 Posts	The boot light is on the same circuit as the interior lights and should operate with them in automatic mode when a door/boot is opened.

1st October 2018, 12:25	#7
Bullnose75 Avid contributor Rover 75 Tourer 2.0 V6 LPG Join Date: Apr 2018 Location: Colchester Posts: 210 Thanks: 4 Thanked 50 Times in 39 Posts	I had a flat battery the other morning in my Tourer,11.7 volts. Starter wouldn't turn engine over. Battery is only five months old. Recharged it,put it back on car,checked nothing was left on,lights etc. Flat again next morning 11. 7 volts ish again. Checked for battery drain yesterday with multimeter - showed fluctuating reading between 3.38 amp and 2,75 amp drain with nothing on apart from clock. Only thing i'd fitted recently was a replacement CD changer(which only works when it feels like it) so unplugged that and battery drain went down to a steady 2.5amp,still too high a drain but that pointed me in the right direction. Removed fuse 33 (the radio,audio one) and battery drain went back to a normal less than half an amp drain (.43 actually). When I got the Tourer back in April the radio didn't work until I found the rocker switch someone had fitted under the steering column. Used car like that for a while,turning power to radio on and off with the rocker switch. Tried it without rocker switch and the radio fuse 33 back in and radio has worked fine for months until now. Looking through previous owners pile of bills for parts etc that he'd had fitted to car over the years did show that he'd been fitting brand new batteries every couple of years or so,proper good brand ones not cheapos,so guess he'd been having intermittent flat batteries too until someone sourced the fault to the factory fitted radio. So might be worth you removing fuse 33 to see if prob is radio related on yours too

10th October 2018, 10:54	#9
Mike Noc This is my second home Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4. Join Date: Jul 2009 Location: Hampshire Posts: 11,550 Thanks: 3,470 Thanked 3,119 Times in 2,247 Posts	Did you leave the boot open and see if the light went out after 15 minutes or so as it should? If it does stay on continuously then it could well be your fault, but these battery drains can come and go, especially if related to water ingress where the car gets soaked one week and dries out the next.

4th April 2019, 21:17	#10
Shide Avid contributor Rover 75 1.8T Join Date: Jun 2015 Location: Ash Vale Posts: 133 Thanks: 5 Thanked 13 Times in 10 Posts	I think I have sussed out the battery 'leak'. The problem appears to be the alternator. Unplugged the multi-pin plug at the rear and left it for a few days. Plugged it back in and she fired up with no problem. If I had left it for the same time 'plugged in' the battery would be flat. So, why would the power drain out through the alternator?