Hood Open or Closed for Trickle Charge?

Rupes · 01-02-2014, 07:38 AM

Does it matter? I always seem to see hoods slightly popped (but not open) when trickle charging. If I close the hood is there any risk of the positive terminal touching something inside? Just never quite understood the rational one way or another.

fbm3cab · 01-02-2014, 08:00 AM

I don't think it makes a difference but my hood is slightly popped open because as you indicated I don't want to take a chance of the leads contacting the closed hood.

My car is also not locked when on the charger because I assume the hood has a switch for open and close that is linked to the alarm system and if this is the case then the next question would be
Is it okay to lock and arm the system if the hood is open?

alee0729 · 01-02-2014, 08:13 AM

If you're going to do frequent trickle charging, I suggest using the quick release cable with the O-ring mounts that go on the battery terminals in the trunk. The trunk closes fine with the connection in place -- just be careful and don't slam it over the cable and it'll latch with a gentle push, and the alarm will arm as well. This is how I keep my car, and have no issues.

tjsabec · 01-02-2014, 08:34 AM

I put a microfiber towel between my paint and the charger cable and allow the hood to "sit down" without latching. This reminds me the charger is hooked up and also makes it easier to disconnect the charger should I get a nice warm day in the winter.

Pic for reference:

THE TECH · 01-02-2014, 09:59 AM

My hood is popped. No issues whatsoever.

SMG M3 · 01-02-2014, 10:59 AM

You're hood does not have to be completely open id bet the latches would fail in the cold and slam shut.

THE TECH · 01-02-2014, 11:01 AM

Quote:

Originally Posted by SMG M3

You're hood does not have to be completely open id bet the latches would fail in the cold and slam shut.

It does not have to be open, that is correct. Latches fail? The hood uses a strut. It is not going to fail due to being open.

Rupes · 01-02-2014, 11:12 AM

Quote:

Originally Posted by alee0729

If you're going to do frequent trickle charging, I suggest using the quick release cable with the O-ring mounts that go on the battery terminals in the trunk. The trunk closes fine with the connection in place -- just be careful and don't slam it over the cable and it'll latch with a gentle push, and the alarm will arm as well. This is how I keep my car, and have no issues.

I thought BMW advised against charging directly to the battery and to use the terminals under the hood instead. Something to do with the intelligent energy management system or something?

Prince_of_Persia · 01-02-2014, 12:33 PM

I completely close my hood when I charge my battery, no issue at all.

BPMSport · 01-02-2014, 04:17 PM

I leave mine unlatched but open. No issues leaving it completely open. Careful fully closing it as you may hurt the wire. Not a problem using the engine jump terminals.

gazosnic · 01-02-2014, 06:13 PM

I have a cheapo harbor freight trickle charger... is that safe to use on our cars? How long do trickle chargers generally take to complete a full charge if the battery is relatively low?

alee0729 · 01-02-2014, 06:14 PM

Quote:

Originally Posted by Rupes

I thought BMW advised against charging directly to the battery and to use the terminals under the hood instead. Something to do with the intelligent energy management system or something?

You should never jumpstart at the battery, but for trickle charging, it is completely fine.

alee0729 · 01-02-2014, 06:19 PM

Quote:

Originally Posted by gazosnic

I have a cheapo harbor freight trickle charger... is that safe to use on our cars? How long do trickle chargers generally take to complete a full charge if the battery is relatively low?

About 12-14 hours.

As long as the charger knows when to stop, it's fine. Trickle chargers aren't just about putting energy back in the battery, but also to change the pace of charging and knowing to stop when full. Ctek and Deltran are the two most popular ones out there... they're often sold rebranded by car manufacturers as well.

///M Power-Belgium · 01-02-2014, 06:27 PM

Quote:

Originally Posted by alee0729

About 12-14 hours.

As long as the charger knows when to stop, it's fine. Trickle chargers aren't just about putting energy back in the battery, but also to change the pace of charging and knowing to stop when full. Ctek and Deltran are the two most popular ones out there... they're often sold rebranded by car manufacturers as well.

Spot on ! My CTEK in action..

SWOT1 · 01-02-2014, 07:19 PM

Deltran. Hood closed. Run cable thru front between light and grille... never an issue.

auggiem3 · 01-02-2014, 07:54 PM

Quote:

Originally Posted by alee0729

You should never jumpstart at the battery, but for trickle charging, it is completely fine.

Good to know - I've been trickle charging in the trunk for a few weeks and got worried at all the hood open references.

G80indy · 01-02-2014, 08:11 PM

Quote:

Originally Posted by ///M Power-Belgium

Spot on ! My CTEK in action..

this one's the best for the AGM battery...
but why aren't you in AGM/winter mode (snowflake)?

///M Power-Belgium · 01-03-2014, 05:15 AM

Quote:

Originally Posted by 330indy

this one's the best for the AGM battery...
but why aren't you in AGM/winter mode (snowflake)?

Agreed i know about the snowflake,it's winter in Belgium but for the moment we have here 10° Celsius , and in my garage i have 18°

Hope that it stay's this way and BTW...good remark of you

sachaja · 01-06-2014, 11:34 AM

I store mine in a garage w/ no power outlets . Any suggestions on how to keep my battery fresh ? A trickle charger requires A/C power . I'm not sure about hooking it up to one of those portable jump starter batteries because it's not really a "trickle charger". I don't want to pull the battery out if I don't have to. I've seen a few solar trickle chargers advertised. I'm not sure how well they work and it might be hard to find a solar light source. The garage has no windows.

THE TECH · 01-06-2014, 11:35 AM

I definitely would not use a jump start unit. What about a long extension cord from inside the house?

tmntmn · 01-06-2014, 11:45 AM

Quote:

Originally Posted by tjsabec

I put a microfiber towel between my paint and the charger cable and allow the hood to "sit down" without latching. This reminds me the charger is hooked up and also makes it easier to disconnect the charger should I get a nice warm day in the winter.

Pic for reference:

This is the same way i have my Deltran battery tender hooked up to my car, with no issue having the hood slightly open

sachaja · 01-06-2014, 04:01 PM

Quote:

Originally Posted by THE TECH

I definitely would not use a jump start unit. What about a long extension cord from inside the house?

The car is not stored next to the house

01-02-2014, 07:38 AM	#1
Rupes Major 1055 Rep 1,459 Posts Drives: F87 M2 (current), E90 330xi (w Join Date: Apr 2013 Location: Oregon iTrader: (0)	Hood Open or Closed for Trickle Charge? Does it matter? I always seem to see hoods slightly popped (but not open) when trickle charging. If I close the hood is there any risk of the positive terminal touching something inside? Just never quite understood the rational one way or another.
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01-02-2014, 08:00 AM	#2
fbm3cab Second Lieutenant 35 Rep 221 Posts Drives: M3 Join Date: Aug 2013 Location: B.C. Canada iTrader: (0)	I don't think it makes a difference but my hood is slightly popped open because as you indicated I don't want to take a chance of the leads contacting the closed hood. My car is also not locked when on the charger because I assume the hood has a switch for open and close that is linked to the alarm system and if this is the case then the next question would be Is it okay to lock and arm the system if the hood is open?
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01-02-2014, 08:13 AM	#3
alee0729 Lieutenant 175 Rep 586 Posts Drives: 2013 E92 M3, 2018 Tesla 3 Perf Join Date: Mar 2013 Location: New York, NY iTrader: (0)	If you're going to do frequent trickle charging, I suggest using the quick release cable with the O-ring mounts that go on the battery terminals in the trunk. The trunk closes fine with the connection in place -- just be careful and don't slam it over the cable and it'll latch with a gentle push, and the alarm will arm as well. This is how I keep my car, and have no issues. __________________ 2013 E92 M3 (the weekend good weather car), 2018 Tesla Model 3 Performance (the 20k mi/yr beater)
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01-02-2014, 08:34 AM	#4
tjsabec Captain 53 Rep 620 Posts Drives: 2008, e90, alpine white, 6mt Join Date: Aug 2011 Location: Morgantown, wv iTrader: (2)	I put a microfiber towel between my paint and the charger cable and allow the hood to "sit down" without latching. This reminds me the charger is hooked up and also makes it easier to disconnect the charger should I get a nice warm day in the winter. Pic for reference: Last edited by tjsabec; 01-02-2014 at 03:42 PM..
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01-02-2014, 09:59 AM	#5
THE TECH BimmerPost Supporting Vendor 307 Rep 13,093 Posts Drives: BPMsport 2012 E92 M3 Join Date: Jun 2011 Location: Kansas iTrader: (45) Garage List 2013 Nissan GTR [0.00] 2019 Sierra Denali ... [0.00] 1999 Nissan Silvia [0.00] 1999 Nissan Skyline ... [0.00] 1998 Toyota Supra [0.00]	My hood is popped. No issues whatsoever.
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01-02-2014, 10:59 AM	#6
SMG M3 Private First Class 23 Rep 159 Posts Drives: 08 M3 6MT Join Date: Aug 2012 Location: cental ma iTrader: (0)	You're hood does not have to be completely open id bet the latches would fail in the cold and slam shut. __________________ Jerez Black: 6MT: Lux: 35% Tint: IND gills ,grill , reflectors: K&N Filter: ACM exhaust mod: Dinan pulley
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01-02-2014, 12:33 PM	#9
Prince_of_Persia Colonel 248 Rep 2,513 Posts Drives: 6MT E92 M3 Join Date: Aug 2010 Location: Vancouver, BC iTrader: (1)	I completely close my hood when I charge my battery, no issue at all.
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01-02-2014, 04:17 PM	#10
BPMSport BimmerPost Supporting Vendor 3387 Rep 7,541 Posts Drives: Harrop M3 / F10 M5 / F82 M4 Join Date: Apr 2008 Location: SoCal iTrader: (9) Garage List 2000 BMW M5 [0.00] 1990 BMW 735i Turbo [0.00] 2008 BMW M3 [7.50] 2015 BMW M3 [0.00] 2015 BMW M5 [0.00]	I leave mine unlatched but open. No issues leaving it completely open. Careful fully closing it as you may hurt the wire. Not a problem using the engine jump terminals. __________________ -----\| Like us on Facebook \| Instagram \|\| Tuning Information \| Remote Coding \|----- ----Visit us at www.BPMSport.com - Emotion. Driven. \| Toll Free: (888) 557-5133----
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01-02-2014, 06:13 PM	#11
gazosnic Major 108 Rep 1,042 Posts Drives: bmw m3 Join Date: Feb 2010 Location: chicago iTrader: (3)	I have a cheapo harbor freight trickle charger... is that safe to use on our cars? How long do trickle chargers generally take to complete a full charge if the battery is relatively low?
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01-02-2014, 07:19 PM	#15
SWOT1 The Hammock Man 493 Rep 593 Posts Drives: X3MC, X3 M40i, E93 M3 Join Date: Jan 2013 Location: Orlando, FL iTrader: (0) Garage List 2009 BMW E93 M3 [8.00] 2020 BMW X3M Comp. [0.00] 2018 BMW X3 M40i [9.00]	Deltran. Hood closed. Run cable thru front between light and grille... never an issue. __________________ - '20 X3MC \| Alpine White \| Black Alcantara/Midrand Beige \| loaded \| 295/265 PS4S - '09 E93 M3 \| Alpine White \| Bamboo Beige Novillo \| DCT \| loaded \| Chrome M220 Wheels - 275/255 PSS
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01-06-2014, 11:34 AM	#19
sachaja Private 16 Rep 73 Posts Drives: 2008 BMW E92 M3 Join Date: Oct 2013 Location: USA iTrader: (0)	No power outlets I store mine in a garage w/ no power outlets . Any suggestions on how to keep my battery fresh ? A trickle charger requires A/C power . I'm not sure about hooking it up to one of those portable jump starter batteries because it's not really a "trickle charger". I don't want to pull the battery out if I don't have to. I've seen a few solar trickle chargers advertised. I'm not sure how well they work and it might be hard to find a solar light source. The garage has no windows.
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01-06-2014, 11:35 AM	#20
THE TECH BimmerPost Supporting Vendor 307 Rep 13,093 Posts Drives: BPMsport 2012 E92 M3 Join Date: Jun 2011 Location: Kansas iTrader: (45) Garage List 2013 Nissan GTR [0.00] 2019 Sierra Denali ... [0.00] 1999 Nissan Silvia [0.00] 1999 Nissan Skyline ... [0.00] 1998 Toyota Supra [0.00]	I definitely would not use a jump start unit. What about a long extension cord from inside the house?
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