Jump starting another car

[littlescrote]

I have been following this thread with interest and have been looking at emergency power packs. But before investing in one, from the pictures on websites it seems that the connecting leads are very short. Long enough, of course, to attach to the terminals of a battery but not long enough to connect to the 'jump start' connection terminals designated in the Outlander handbook. To those that have used one of these power packs, do you connect to the designated under-bonnet terminals using extension leads, or connect direct to the aux battery under the floor?

Connecting to the Aux battery under the floor requires you to take the floor up.

 

[NightPHEVer]

I have been following this thread with interest and have been looking at emergency power packs. But before investing in one, from the pictures on websites it seems that the connecting leads are very short. Long enough, of course, to attach to the terminals of a battery but not long enough to connect to the 'jump start' connection terminals designated in the Outlander handbook. To those that have used one of these power packs, do you connect to the designated under-bonnet terminals using extension leads, or connect direct to the aux battery under the floor?

Good point - the 'designated' earth point in the bonnet on a PHEV is a long way from the positive connection. You'll either need a long earth lead or to find an earth point closer to the positive connection. Usually the case that any clean, metal bracket will act as an earth point (as far as I know this shouldn't cause any problems). I've jump started a lot of cars and as long as the negative cable gets a good connection to earth it will work. I'll have to take a look in my PHEV and remind myself where there's a suitable earth point nearer the main fuse block where the positive lead connects.

But in answer to your question you connect the jump pack in the bonnet. If there's any juice at all left in the 12v there's no advantage to connecting it straight to the battery (as previously mentioned it's difficult to get to). However, if the 12v is totally flat and dead then a jump pack is unlikely to revive the system. I can't be 100% sure of this with the Mitsubishi PHEV as I've never actually needed to know, but with a Ford Kuga PHEV I have (many times - I worked in a Ford dealearship), and if the 12v is totallyflat you have to disconnect the 12v terminals (KUGA 12v also in the boot under the floor) recharge the 12v with a charger and then reconnect it. There comes a point with all car 12v systems where the battery can be so completly dead a jump pack (even a proper Snap-on large lithium pack) will not work, and a battery charger won't recharge it. This normally only happens when the car has not been used for a long time though. Sometimes you can piggy-back the charger to a good 12v battery and connect the good battery to the dead battery as it's charging, but I wouldn't trust the dead battery for future use.

Below photo - this appeared to work - jump pack earthed on suspension bolt which looked to me like a 'substantial, unpainted point on the chassis of the vehicle' which is what the instructions with the jump pack advise. My 12v isn't actually flat here but nothing went pop when I connected it (vehicle was obviously switched off when I connected it) so as far as I know this would work. Since I flattened my 12v about 7 years ago I've never actually done it again. That was of course before I bought the £60 jump pack. If the 12v was flat you'd have to leave the pack on for a while before trying to boot-up the system. Basically, follow the instructions supplied with the jump pack. Although no, hang on, you probably can't. The instructions on my jump pack don't actually include any specific information regarding its use on PHEV or full EV cars. Bit behind the curve there Halfords. I don't actually know if all EV cars have a 12v auxiliary battery but I would think they do. I know the Ford Mustang Mach-E does - and I know how to jump 'start' one too.

This is a quite small Halfords jump starter (6000mAh) suitable for engines up to 2 litre. Although engine size suitablity isn't an issue with a PHEV or EV as the jump pack doesn't have to turn-over a sizeable motor like you'd want it to in a conventional petrol or diesel car. As far as I know you could use a more powerful jump pack - suited to starting much bigger conventional engines - if that's what you have.

I'd welcome anyone who knows more about all this than I do to comment. Most of my knowledge is based on jump starting a lot of different cars without causing any damage in the process. In the best tradition of the internet, I hope I haven't given any incorrect advice here....

 

[NightPHEVer]

Further to the above, I've been reading about jump starting a pure EV and it would seem some posh Teslas actually have a low-voltage lithium 12v battery, not conventional lead acid. So you'd have to be very careful about 'jump' starting one of those! Seems you can use a suitable lithium jump pack but I wouldn't know about anything to do with using a conventional 12v lead acid battery or jump leads to another car. Tesla Owner's manual says: "If jump starting Model 3 using another vehicle, refer to the vehicle manufacturer's instructions" whatever that may mean...

 

[HeliNurse]

Just bought the Gooloo A3 off ebay with the intention of jump starting the other, ICE car. Our other vehicle is a LR Disco 3 and I would not want to try and jump that from the PHEV. A mate has the A3, it jumped his Diesel HiLux no problem and the compressor reinflated a tire from 12 psi without drama.