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Old 25th April 2019, 09:36   #11
MSS
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Agree with the post above. A current of 2.5A means that the culprint will be consuming around 25 to 30W. Any part consuming this level of power will be warm to touch.

I would put a fully charged battery on the car on a cold morning, put the electronics in sleep mode for about an hour and then try to find the culprit by touching the various possible items.
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Old 25th April 2019, 10:13   #12
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Default Thanks folks

Thanks for the suggestions. At work currently but will try some more investigations based on your suggestions later today.
No recent audio mods or dashcams. Unfortunately my car doesn't get luxuries at 210k its a workhorse that get serviced and maintained regularly!
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Old 25th April 2019, 10:27   #13
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Default Power drain

I will try disconnecting alternator first as agree that 2.5A is a substantial drain and one of my concerns has been something must be getting warm / hot and maybe fire risk !!
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Old 25th April 2019, 10:50   #14
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Quote:
Originally Posted by MrBIW View Post
I will try disconnecting alternator first as agree that 2.5A is a substantial drain and one of my concerns has been something must be getting warm / hot and maybe fire risk !!
Have had very similar issue for a while... Eventually it turns out that starter motor was the issue!

Try sorting out the starter motor and alternator first
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Old 25th April 2019, 12:47   #15
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Default Power drain

Lunchtime progress ..... I have isolated starter and alternator by removing main +ve connection at battery and using MMeter to connect from battery +ve to main fusebox input. (cable disconnected). I believe this means battery is only connected to car systems. Still reads 4.7 A at connection dropping to 2.6A after approx 2 mins. I didn't have time to wait longer but I recall from previous experience that I could see 'milliamps' after 2 minutes before this.

For cb750chris, Many thanks for the tables. I will try to use them later to at least check the 6 'square' fuses I can't extract. I know they are not standard spades but i'm looking for Amps not milli's.

For 'Blackrose'.... looks a useful tool and will probably get one anyway but doesn't help with the 'mini spades' in the cabin fusebox ! Thanks anyway.

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Old 25th April 2019, 19:35   #16
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All hail cb750chris
It would appear glowplugs were causing power drain. Have disconnected FL6 100A and now have quiescent current of 18 milliamps after approx 10mins. Question now is why ? I will check the GPlug relay at the weekend but also have a niggling suspicion that the recent ambient temp sensor issue may be implicated. Glow plug control is, i believe, linked to external air temperature.
However, it would seem I may get to keep 'old faithful' a while longer! Just non cooling aircon and overtightened wheel bolts to go!
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Old 25th April 2019, 20:01   #17
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Quote:
Originally Posted by MrBIW View Post
All hail cb750chris
It would appear glowplugs were causing power drain. Have disconnected FL6 100A and now have quiescent current of 18 milliamps after approx 10mins. Question now is why ? I will check the GPlug relay at the weekend but also have a niggling suspicion that the recent ambient temp sensor issue may be implicated. Glow plug control is, i believe, linked to external air temperature.
However, it would seem I may get to keep 'old faithful' a while longer! Just non cooling aircon and overtightened wheel bolts to go!
I would disconnect the glow plug relay, then never worry about it again, unless you plan on going somewhere it's -15 degrees, you won't need them

It's certainly a new one on me, I've never experienced the glow plug relay as a reason for the BCU not going to sleep, which is why the current draw is 2.5A

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Old 25th April 2019, 21:16   #18
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Quote:
Originally Posted by MrBIW View Post
All hail cb750chris
It would appear glowplugs were causing power drain. Have disconnected FL6 100A and now have quiescent current of 18 milliamps after approx 10mins. Question now is why ? I will check the GPlug relay at the weekend but also have a niggling suspicion that the recent ambient temp sensor issue may be implicated. Glow plug control is, i believe, linked to external air temperature.
However, it would seem I may get to keep 'old faithful' a while longer! Just non cooling aircon and overtightened wheel bolts to go!

In the UK it will start up fine without need for glow plugs to be working. The relay fails because it is in the plenum chamber, which sometimes becomes flooded with water, if you fail the check the drains are clear.
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Old 25th April 2019, 21:34   #19
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Default Battery drain

Thanks Harry,
To be honest the plenum issue threw me at the start of this problem. As I said in one of my earlier replies my car doesn't get many luxuries but I do try to keep on top of routine maintenance...Plenum drains being one of them. I know it is bone dry in there but nevertheless it was one of the first areas I checked. apart from a few leaves and a reminder to change the cabin filter i didn't see any problems.
This car has done 120k for me in the last 4 years and being my 5th Ztt you get used to some of their 'achilles heals' however sometimes you are too close to the problem and the value of the forum to me is that it sometimes it takes others to refocus your attention on basics.
Again, many thanks to all who took the time to assist.
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