Portable Power Jump Start

[Kopper]

Hi

I have one of those portable Battery packs to jump start cars which I had from my previous Rav 4. The pack will jump start cars up to 2.5L engines but does anyone know if would be enough to jump start my RX450h with the smaller 12v Battery? 

I just need to know if I need to invest in another power pack just in case I ever need it. 

This is my current device :

https://www.amazon.co.uk/dp/B01DVSSCG6/ref=cm_sw_r_cp_apa_i_iMYbFbB1P67ES

Thanks

[Herbie]

Without a doubt, yes it will.

A conventional car has a starter motor that takes upwards of 300A to crank the engine, but a hybrid car doesn't have a starter motor as such and all the 12V Battery does is to boot the computers and pressurise the brake system, which takes less than 20A to do.

In fact, 'starting' a hybrid takes so little current that you could in theory use a pack of 8 AA batteries - but I wouldn't advise trying it 😄

[Kopper]

52 minutes ago, Herbie said:

Without a doubt, yes it will.

A conventional car has a starter motor that takes upwards of 300A to crank the engine, but a hybrid car doesn't have a starter motor as such and all the 12V battery does is to boot the computers and pressurise the brake system, which takes less than 20A to do.

In fact, 'starting' a hybrid takes so little current that you could in theory use a pack of 8 AA batteries - but I wouldn't advise trying it 😄

Thanks. 

Do you recommend jump starting from the back Battery or from the terminals under the bonnet? 

[Barry14UK]

If I remember correctly, Herbs has his neatly installed in the boot area ready for use if necessary.  As he implies, you don't really 'jump start' the engine,  you supplement or virtually replace the 12v Battery this way to wake up the computers etc which then enable the traction Battery to fire up the engine as necessary.  As I see it, you could have a well charged traction Battery but it can't do it's job unless the 12v Battery is able to initiate the process.  Of course it's best to avoid letting the 12v Battery ever drop to a level where it fails to do this because each time this happens it will reduce the life of the expensive 12v Battery.  Therefore, if the car is not used regularly say once every couple of weeks or so, it makes sense to use a smart charger or one of those solar jobbies.  Naturally, an older Battery is going to hold it's charge less well than a newer one so that would affect need for checking/charging frequency. 

[Herbie]

56 minutes ago, Kopper said:

Do you recommend jump starting from the back battery or from the terminals under the bonnet?

It doesn't matter, just personal preference and whichever is easier for you.

As Barry says above, I did install a more convenient 'jump start socket' in the boot at one time, but then I discovered that the tailgate can't be opened if the 12V Battery is flat. I then decided to install another socket in a really convenient place but I still haven't been able to finish the job off yet as I'm still suffering from extreme vertigo when I have to get my head into strange positions.

 

 

[Illogan]

During this current health scare I, (Like a few others) discovered that the 12v Battery on our car was 'tired' and let us down a couple of times on our most infrequent journeys.

I used our Genius Battery pack , and have found that using the 'emergency post' inside the under-bonnet fuse-box an absolute doddle, and it only neccessitates removing just the one  (engine bay)panel above the fusebox    .

And it takes so little drain from the Genius pack, I've not needed to recharge it at all

Edited July 10, 2020 by Illogan
Spolling misstakes!

[flookyk]

20 hours ago, Kopper said:

Hi

I have one of those portable battery packs to jump start cars which I had from my previous Rav 4. The pack will jump start cars up to 2.5L engines but does anyone know if would be enough to jump start my RX450h with the smaller 12v battery? 

I just need to know if I need to invest in another power pack just in case I ever need it. 

This is my current device :

https://www.amazon.co.uk/dp/B01DVSSCG6/ref=cm_sw_r_cp_apa_i_iMYbFbB1P67ES

Thanks

I bought one from Halfords myself for 2.0l and used it once on mine because I had not realised you needed to do a weekly hour with the system at Ready rather than just a 4 mile run around the block with a downhill section .. that was enough to keep the main Battery up to charge but not the 12V one.

It worked perfectly and I used the under bonnet connections to start it up... I now keep this in the door pocket just in case.

[Illogan]

14 hours ago, Illogan said:

During this current health scare I, (Like a few others) discovered that the 12v battery on our car was 'tired' and let us down a couple of times on our most infrequent journeys.

I used our Genius battery pack , and have found that using the 'emergency post' inside the under-bonnet fuse-box an absolute doddle, and it only neccessitates removing just the one  (engine bay)panel above the fusebox    .

And it takes so little drain from the Genius pack, I've not needed to recharge it at all

As an update to the above: - This morning I found that Noco (Genius) sell a bespoke cable to link the GB70 booster/jump starter directly to the OBD-II socket, thus powering all the 12v service settings (doors, alarms, seats etc etc) and allows one (me!) to change the 12v Battery in comfort, and without running the risk of losing any of the settings.

At £20 (!) it may be an expensive luxury, but it will provide me with piece of mind when removing the Battery, and will come in useful when doubtless lending to friends!

[Herbie]

17 hours ago, Illogan said:

have found that using the 'emergency post' inside the under-bonnet fuse-box an absolute doddle, and it only neccessitates removing just the one  (engine bay)panel above the fusebox 

You're right, it is a doddle and much easier than getting at the Battery under the boot floor. However, given that I'm clumsy at the best of times I just know that if I needed to do it on a cold, wet, windy night I'd either break or lose the little plastic 'poppers' that hold the engine cover on, which is why I decided to bring the jump point inside the cabin.

2 hours ago, Illogan said:

At £20 (!) it may be an expensive luxury,

That is indeed, expensive.

Assuming your failing Battery still has some juice left (if it hasn't then there's no settings to save anyway) then all you have to do is to ensure an unbroken 12V supply to the car. A cheaper alternative would be to drill a small hole in the top of the lead terminals of the existing Battery and use either croc clip to croc clip leads or croc clip to banana plug and just connect from lead terminal to the clamp that you're undoing.

These are available for just over a couple of quid a pair from eBay and will do just exactly the same job:

https://www.ebay.co.uk/itm/1m-Banana-Plug-to-Crocodile-Alligator-Clip-Multi-Meter-Test-Leads-Red-Black/112866954164?hash=item1a47650bb4:g:BtUAAOSw9GhYa8j8

Another alternative would be to get an OBD2 plug with 'fly leads' at the other end and just connect the Genius to the correct wires. The example below is just under seven quid delivered from here.

[Illogan]

Herbs!

 

Of course!    (Doh! - I hadn't considered that) - but will now purchase an OBDII plug and fly leads!

Many thanks - - (this has been a salutory lesson in "Think before I type")

Cheers!

[Barry14UK]

I think we are looking at different situations here and I wonder whether a bit of preliminary work could lead to less hassle when needed as problems tend to happen at awkward times.

Is this feasible?   

                                                                                                                                                                                                                                                           

* Bolt onto accessible underside of car a bracket that will carry a waterproof plug for connection to mains and to take mains power inside of car boot when wanted.

* Install smart charger in boot. 

* Install Power pack in boot.

*  convert an existing socket to make permanent (or add new) inside cabin so smart charger can be connected to it and then to 12v system when required.  All that would need to be done then would be to connect external plug to mains.

*  Power pack could also be boosted as required by connection to mains via the external socket.

*  This would save raising bonnet or boot lid and emptying out contents in boot.

*  When 12v battery eventually needs changing the power pack can be readily connected inside the car without other temporary connections and without losing settings.

I think this could be made to work  - it's just that more needs to be done at the outset to make it easier when situation requires.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

i  

[Herbie]

Well I've finally managed to finish off the job!

Unfortunately my back was killing me and my head was still a little 'spinny' so I have to confess that I just ploughed on to get it done and forgot to take many photos. However, there are three below.

The first one shows that just up in the passenger footwell where the carpet ends, there's a big rubber grommet that takes the existing wiring loom through the bulkhead. It wasn't too difficult to cut a hole in this grommet to take my conduit out the same way. From there I just ran it along under the carpet and took the centre console trim panel off to get it in behind there to where I wanted it - nothing can be seen and no one would know it's there.

The second photo shows the wiring at the engine bay fuse box. Technically I should have used the 12V post under the red cover as that is the dedicated jump start connection, but the yellow insulation on the ring terminal made that quite difficult and it was easier to 'break out' of the other one. They're both permanently energised and a direct connection back to the Battery anyway so it doesn't really matter.

Because my new wires will be permanently connected to the Battery it's essential to fuse the circuit, so I installed an in-line fuse-holder and put a 15A fuse in it. This will be plenty big enough to handle the jump start current but is small enough to protect the cable that I've just installed and prevent a fire in case of a chafed wire/short circuit.

I connected the negative (or earth, if you prefer) wire to one of the bolts nearby.

The final photo shows that it's all working and if I ever need to jump start her then I'll be able to do it from the comfort and dryness of the cabin, no matter what the weather's doing outside

[ColinBarber]

your Battery is looking a bit discharged - you may get the opportunity to test out your new installation soon 😉

[Herbie]

1 hour ago, ColinBarber said:

your battery is looking a bit discharged - you may get the opportunity to test out your new installation soon 😉

That's true Colin, although I'm hoping it's because I've had the doors open while I've been doing the work. We'll be having a trundle up the motorway tomorrow so we'll see what happens 😄

[Delphius1]

On 7/10/2020 at 1:11 PM, Herbie said:

You're right, it is a doddle and much easier than getting at the battery under the boot floor. However, given that I'm clumsy at the best of times I just know that if I needed to do it on a cold, wet, windy night I'd either break or lose the little plastic 'poppers' that hold the engine cover on, which is why I decided to bring the jump point inside the cabin.

That is indeed, expensive.

Assuming your failing battery still has some juice left (if it hasn't then there's no settings to save anyway) then all you have to do is to ensure an unbroken 12V supply to the car. A cheaper alternative would be to drill a small hole in the top of the lead terminals of the existing battery and use either croc clip to croc clip leads or croc clip to banana plug and just connect from lead terminal to the clamp that you're undoing.

These are available for just over a couple of quid a pair from eBay and will do just exactly the same job:

https://www.ebay.co.uk/itm/1m-Banana-Plug-to-Crocodile-Alligator-Clip-Multi-Meter-Test-Leads-Red-Black/112866954164?hash=item1a47650bb4:g:BtUAAOSw9GhYa8j8

Another alternative would be to get an OBD2 plug with 'fly leads' at the other end and just connect the Genius to the correct wires. The example below is just under seven quid delivered from here.

Herbie, the other useful addition is a solar panel with an OBD2 socket on it, so the solar panel is always charging the Battery and keeping it topped up. 

The advantage of the OBD2 connector is so many cars have them these days and the connections are standard. So you can use the solar panel on any car. 

Depending on which car we are running at the time, the solar panel I made switches duty between my car and the wife's. It works seamlessly on my Lexus and her Hyundai. The panel just sits propped up on the dash inside the car. The panel is a 5w solar panel so it makes enough juice even behind the glass windscreen.

Either car can be left as long as you like with the panel plugged in and still starts up when we need it. 

The other advantage is no trailing mains wires like a trickle charger and you don't have to wait around for a power pack to bring a dead Battery up to voltage. The car starts first time because the Battery is already charged!

The only downside is the car does need to be in the daylight. But then cars in garages usually have access to power these days. 🙂

The only disadvantage I can see if trying to hook up a charger via the OBD2 is the wiring isn't specced to take much in the way of current. If the flat Battery demands too much current from the charger pack then you could fry the 12v lead to the OBD2 socket. At least the solar panel is only trickle charging.

 

[ISJason]

I bought one from Halfords myself for 2.0l and used it once on mine because I had not realised you needed to do a weekly hour with the system at Ready rather than just a 4 mile run around the block with a downhill section .. that was enough to keep the main battery up to charge but not the 12V one.
It worked perfectly and I used the under bonnet connections to start it up... I now keep this in the door pocket just in case.

Hi just wondered how does that starter compared with others? Did you have a look at a range of them? I’m thinking of getting one myself but wasn’t sure which was the best one to go for. Thanks


Sent from my iPad using Tapatalk

[Herbie]

8 minutes ago, ISJason said:

Hi just wondered how does that starter compared with others? Did you have a look at a range of them? I’m thinking of getting one myself but wasn’t sure which was the best one to go for. Thanks


Sent from my iPad using Tapatalk

They're all really much of a muchness, they all work in the same way and the only real way they differ is just in capacity and how big an engine they will start.

Our hybrids take very little to start them so a low-capacity unit, say like Keith's above that is suitable for a 2.0l engine, would be more than adequate. However, my own personal view is that I would be very upset with myself if I ever had to turn away someone who was in need of a jump start, so I went for a higher-capacity unit capable of jump starting up to a 6.0l petrol engine and it was only about £20 more.

Other than that there's not really a lot to say about them.

[ISJason]

thanks for your prompt reply


Sent from my iPad using Tapatalk

[Barry14UK]

Herbs,

Thank you for posting and hope you have not badly strained your back.  I empathise as I also have back trouble and it takes a few days to recover after contortions.

I am actively looking into installing a 'jump start' and like you have concluded that connections indirectly to the 12v Battery are more easily made from under the bonnet rather than directly to the Battery in the boot.  I follow the connections you made under the bonnet and how you brought extended leads through the bulkhead.  I believe the unit you installed comes with the little diode housing on the positive lead to stop backfeed to the jump start.  Did you include this on the extended cables you made up?  I assume your leads terminate in the socket you showed where your meter was hooked up. Presumably you would plug the jump start into this socket when needed.

[Herbie]

13 hours ago, Barry14UK said:

Thank you for posting and hope you have not badly strained your back.  I empathise as I also have back trouble and it takes a few days to recover after contortions.

Thanks Barry.

Thankfully it's now back to what's 'normal' for me although the pain never goes away completely, not even with modern-day strong analgesics.

13 hours ago, Barry14UK said:

I believe the unit you installed comes with the little diode housing on the positive lead to stop backfeed to the jump start.  Did you include this on the extended cables you made up?

That's a very good point Barry and one that I didn't consider to be honest. I assumed that the little housing on the positive lead contained something to protect the jump start pack electronics from the effects of an accidental reverse polarity connection. The plug and socket I've installed are keyed, therefore making reverse polarity impossible, so I didn't see the need to install any diodes for that reason.

I didn't consider the fact that once the hybrid system achieves READY mode then approximately 14.5V will be coming from the converter and trying to get to the jump start pack, so I'll do some research and some tests, and get back to you when I know more about that.

13 hours ago, Barry14UK said:

I assume your leads terminate in the socket you showed where your meter was hooked up. Presumably you would plug the jump start into this socket when needed.

Yes.

I made a silly schoolboy error and posted 'Part 2' of my little project in this topic, when it should, of course, have been tagged onto the end of 'Part 1'.

I'm hoping that the mods or admin bods will be able to copy from here to there to preserve continuity of both topics, but for now here's a link to Part 1:

 

 

[Barry14UK]

Thank you for your response Herbs.

These 'jump starts' are great but need treating with respect otherwise can smoke or even explode as was shown with a market leader in a video but not in the one I will link to.

I found it interesting to watch this tear down of a defective unit and from about 13.06 on (if you don't wish to watch the whole thing), the guy opens the diode pack and shows the importance of this, hence I mentioned it to you.  

 

[Delphius1]

On 7/15/2020 at 3:26 PM, Barry14UK said:

Thank you for your response Herbs.

These 'jump starts' are great but need treating with respect otherwise can smoke or even explode as was shown with a market leader in a video but not in the one I will link to.

I found it interesting to watch this tear down of a defective unit and from about 13.06 on (if you don't wish to watch the whole thing), the guy opens the diode pack and shows the importance of this, hence I mentioned it to you.  

 

Godda Love Big Clive, he's on my YouTube subscription list. 🙂

[Barry14UK]

6 hours ago, Delphius1 said:

Godda Love Big Clive, he's on my YouTube subscription list. 🙂

Yes he seems to fumble his way through at times and takes some risks.  However, for somebody who has done over 1,660 videos, mainly pulling electronic items apart and often modifying them, he has acquired vast experience and tells it how it is highlighting defiences rather than extolling product virtutes as some do who are promoting certain products for manufacturers.

[Paul Mingay]

Looking at these with interest ,,and out of interest would on of those plug into the cigarette (12v) boosters be safe?

[Herbie]

14 minutes ago, Paul Mingay said:

Looking at these with interest ,,and out of interest would on of those plug into the cigarette (12v) boosters be safe?

Safe, yes; useful, no.

The cigarette lighter sockets are only energised when the car is on, which means that when the car is off (as in the case of a flat battery) there is no pathway for the jump starter to get power into the 12V Battery.