Parasitic Draw
#1
Parasitic Draw
I decided to check the draw on my LR2 after reading a recent post on the same topic. The spec says less than 25mA after allowing the shutdown process to complete (wait at least 35 minutes).
This morning I checked after the car sat overnight. It's measuring quite high at ~330mA, or one-third of an amp. This is current on the accessory circuit from the battery, the heavier starter wire shows no current flow. The last time I checked (last year) it was within spec.
I pointed my laser thermometer gun at every fuse (all three fuse boxes) to see if any fuse was warmer than the others but they were all stone cold.
I"m aware of the TSB on this issue and I don't fall into that use case. Can't imagine what else it could be or if related to my recent engine swap. Will have to give this more thought and testing, though I'm not sure what else to test.
FOLLOW-UP: I just need to start removing fuses, selectively of course, and watch for a drop in current. I'll post back when I find the culprit.
This morning I checked after the car sat overnight. It's measuring quite high at ~330mA, or one-third of an amp. This is current on the accessory circuit from the battery, the heavier starter wire shows no current flow. The last time I checked (last year) it was within spec.
I pointed my laser thermometer gun at every fuse (all three fuse boxes) to see if any fuse was warmer than the others but they were all stone cold.
I"m aware of the TSB on this issue and I don't fall into that use case. Can't imagine what else it could be or if related to my recent engine swap. Will have to give this more thought and testing, though I'm not sure what else to test.
FOLLOW-UP: I just need to start removing fuses, selectively of course, and watch for a drop in current. I'll post back when I find the culprit.
Last edited by LR2driver; 01-09-2022 at 09:15 PM.
#2
Hi, I had a parasitic draw of around 1.6A and battery used to drain every 8 hours. It is cumbersome to find the exact fuse by pulling them. I don't recommend pulling fuses, as the car will not go to sleep unless locked and a lot of modules will keep active when unlocked.
I tried for two weeks and could not fine the drain. Then I read somewhere on this forum to try a reset and luckily for me it worked. The draw is now around 26mA.
Try this before you do anything else by disconnecting your battery and shorting the positive and negative terminals for around 10 minutes. It will reset all modules back to default and any hung modules or relays.
Did you measure the drain while the car is locked or unlocked? When you unlocked the car in the morning, many modules would have woken up. I had to disable the bonnet sensor, locked the car and checked for the drain after an hour.
The two weeks were so frustrating that i decided to get an Amp-hound-2 so I am ready for the next time this happens. It shows exactly which fuse is drawing current and by how much without pulling the fuses.
I also got a bluetooth battery monitor to help me keep an eye out for parasitic drains and charging.
I tried for two weeks and could not fine the drain. Then I read somewhere on this forum to try a reset and luckily for me it worked. The draw is now around 26mA.
Try this before you do anything else by disconnecting your battery and shorting the positive and negative terminals for around 10 minutes. It will reset all modules back to default and any hung modules or relays.
Did you measure the drain while the car is locked or unlocked? When you unlocked the car in the morning, many modules would have woken up. I had to disable the bonnet sensor, locked the car and checked for the drain after an hour.
The two weeks were so frustrating that i decided to get an Amp-hound-2 so I am ready for the next time this happens. It shows exactly which fuse is drawing current and by how much without pulling the fuses.
I also got a bluetooth battery monitor to help me keep an eye out for parasitic drains and charging.
Last edited by pbraj; 01-10-2022 at 10:15 AM.
#3
The source of the problem appears to be the auto headlights switch when I leave it in the ON position, which I always do. As a test, I turned this switch OFF and checked the mA current flow afterwards, which measured in the single digits. Hurray! Then I turned the switch ON (with the car off and the key not docked) and the current flow spiked and remained high.
This is a known problem for the LR2 that I've read about in the forums although it never affected my vehicle before now. The simple workaround is to turn the light switch to the OFF position before shutting off the car.
I'll try the battery reset and see if that clears it up. The auto lights feature is a nice convenience and I would like to continue using it if I can.
This is a known problem for the LR2 that I've read about in the forums although it never affected my vehicle before now. The simple workaround is to turn the light switch to the OFF position before shutting off the car.
I'll try the battery reset and see if that clears it up. The auto lights feature is a nice convenience and I would like to continue using it if I can.
Last edited by LR2driver; 01-10-2022 at 01:31 PM.
#4
The source of the problem appears to be the auto headlights switch when I leave it in the ON position, which I always do. As a test, I turned this switch OFF and checked the mA current flow afterwards, which measured in the single digits. Hurray! Then I turned the switch ON (with the car off and the key not docked) and the current flow spiked and remained high.
This is a known problem for the LR2 that I've read about in the forums although it never affected my vehicle before now. The simple workaround is to turn the light switch to the OFF position before shutting off the car.
I'll try the battery reset and see if that clears it up. The auto lights feature is a nice convenience and I would like to continue using it if I can.
This is a known problem for the LR2 that I've read about in the forums although it never affected my vehicle before now. The simple workaround is to turn the light switch to the OFF position before shutting off the car.
I'll try the battery reset and see if that clears it up. The auto lights feature is a nice convenience and I would like to continue using it if I can.
As a side, I did also turn off my DRLs in SDD CCF as well but that not really relevant to your draw issue.
Last edited by ThorInc; 01-10-2022 at 04:36 PM.
#5
https://landroversecrets.com/land-ro...tery-problems/
#6
Yes, that's the dial I'm referring to. This is a known problem that just started happening to me:
https://landroversecrets.com/land-ro...tery-problems/
https://landroversecrets.com/land-ro...tery-problems/
#7
#8
#9
#10
Yes, exactly. I haven't connected it back yet, but one of the technicians i know tell me that the bonnet sensor circuit needs to be kept open after an oil change to successfully reset the service interval. Need to reconfirm this next oil change.
Last edited by pbraj; 01-13-2022 at 04:51 AM.
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LR2driver (01-13-2022)