Hybrid jump start point

[Herbie]

Although our car is used daily my wife doesn't drive, so if I'm incapacitated for any reason I can see that the 12V Battery may be flat before I'm able to drive again.

Of course, Sod's Law dictates that it would be on a cold, rainy day and I'd have to empty the boot of all its contents or risk losing the little plastic clips if I were to remove the engine bay covers to get at that more convenient jump point, so I decided to avoid all that hassle and fit a socket in a convenient and easily accessible place in the boot.

Jump leads are great if there's someone else around to provide a donor Battery but that doesn't always happen, so a while ago I invested in a jump start Battery pack something similar to this one but mine's an earlier model.

The hybrids don't draw a lot of current on startup; you'll see from the photo below that my RX450h only draws 15.32A as opposed to the 300A+ of a traditional starter motor, which means that I can use a small, neat socket instead of something big enough to put the big crocodile clips on. I decided on a panel mount 2 pole Neutrik speakON socket and the corresponding plug. These are actually loudspeaker connectors but they're rated at 30A continuous, so plenty beefy enough to handle the current.

Having chosen a location the first job was to pull out the light to make sure there was enough room behind the panel and that I wasn't going to damage anything with the drill. The wiring to the light looks dodgy but I'm just waiting for a new connector to arrive so it'll be all proper again shortly 😉

Next job was to make sure I could get the cable to the required location so I pushed a piece of old earth cable down from the top and left it in place to use as a draw wire later. Once that was in it was time to drill the hole using a step drill and test fit the socket.

Next job was to get the wires into the conduit, tie the conduit on to the drawrope at the bottom and pull it up through the hole.

Next was termination. My original idea was to use spade connectors but when I pushed the socket back into the hole the connectors came off, so I resorted to soldering them on instead (and forgot to take a photo of that).

Next it was just a matter of routing the conduit round to the Battery and using cable ties to fix it to the other conduits going across the car. Before connecting to the Battery I used my Megger to check for short circuits positive to negative, positive to chassis and negative to chassis, in case anything unforseen had happened. All good, so time to connect to the Battery.

 

Finally, a test of it all and you can see the Battery voltage. All I need to do now is to make up the lead with the speakON plug at one end and the Anderson SB50 connector that plugs into my jump start Battery pack at the other end and, as we say up north, job's a good 'un 😊

 

[GSLV6]

I had my leisure Battery go flat last year.  All I did was connect another small gel Battery across its terminals, enough to power the systems for the hybrid Battery to crank the starter motor.  An hours drive around and all was ok.  I removed the leisure Battery and put it on a deep cycle charge.  It lasted a few months but once you run these right down, chances are (especially if a few years old) they may not recover. Mine was replaced under warranty.  It's only a 5 minute job to remove the Battery to charge it.  In my case I didn't even remove it.  Charged insitu after disconnecting vehicle terminals.

 

Speakon do a dedicated power socket as well as the lower rated sockets:

https://cpc.farnell.com/neutrik/nac3fca/powercon-cable-a-connector/dp/CN04055?mckv=shNG274SO_dc|pcrid|224645161149|kword||match||plid||slid||product|CN04055|pgrid|45968746254|ptaid|pla-576170237002|&CMP=KNC-GUK-CPC-SHOPPING&gclid=Cj0KCQiAj4biBRC-ARIsAA4WaFjQ3Rw621-WJhGUQPMxl1JU4hxpJR5cKuOxBn3Xj14pAe4K96JdllIaAhX-EALw_wcB

This is 20A rated.

 

[Herbie]

1 hour ago, GSLV6 said:

Speakon do a dedicated power socket as well as the lower rated sockets:

I noticed that but I didn't need three poles and, weirdly, the power socket is rated at 20A but the one I used is rated at 30A.

What really drove my decision though is that I already had a surplus socket in my junk box so I only needed to buy the plug 😊

[Gliderpilot]

If it's kept outside you could plug a small solar panel into the OBDII socket and put it on top of the dash, that will keep your Battery topped up.

[Herbie]

5 minutes ago, Gliderpilot said:

If it's kept outside you could plug a small solar panel into the OBDII socket and put it on top of the dash, that will keep your battery topped up.

True, that is another way to solve the problem, but I've already got the jump start Battery pack, I enjoy doing things like this and the whole job only took an hour to do so it kept a bit of boredom at bay for a little while.

[Herbie]

A couple of folks have asked to see the final result so here's a couple of photos just to finish off the job. First one just shows a little modification in that I've added a 30A in-line fuse to the new jump start circuit. Second photo shows the jump start Battery pack with the cable made up and connected. Hopefully I'll never need to use it but at least it's easy to use if I ever do need to.

 

 

[Guest]

Had my RX450h 12v Battery flatten when the car was opened up all day for a full valet recently as I have it for sale currently (I’m retiring so my driving habits are changing, although having had 3 silly offers, I’m thinking of hanging on for a while now), the jump connectors/procedure is pretty clear in the handbook and we got it going again.

To stop this being a problem with it sat for days, I’d previously bought a 12v solar panel, about A4 size, sits on the dash and plugs into the OBD connector, to trickle charge the 12v Battery. Used it on previous cars and it works a treat. Cost about £20.