Jump-start using a Volvo V70? - Martin Wall
Hi

Wanted to jump-start a car using the Volvo V70 as the good-battery car. The manual tells you where to connect cables when you want to jump-start the V70 itself (using terminals under bonnet rather than direct to battery in boot) but not what to do where the V70 is the good-battery car.

So - do I just use the same under bonnet terminals to get at the V70 battery output or do I need to connect directly to the battery terminals in the boot (removing the cover etc.)?

thanks
Jump-start using a Volvo V70? - adverse camber
I would connect direct to the battery. you are taking power from this car.

I never really understood why they say connect to engine block etc when starting, maybe someone could explain. unless it would work even with bad earth strap, and once started the alternator will get the car to journey end ?
Jump-start using a Volvo V70? - Doc
I never really understood why they say connect to engine block
etc when starting,


The safest technique is first connect the positive terminals on both batteries to one another, and then to connect the negative terminal on the good battery to a ground (such as the engine block or frame) on the vehicle with dead battery. The final jumper connection usually sparks, so keeping the spark away avoids any danger of blowing up the battery.


Jump-start using a Volvo V70? - SjB {P}
Agree with the above advice, to which I add that I have used my V70 to jump start several other cars one of which (SAAB 9000 2.3 in the depth of winter) had such a flat battery that none of the dash lights would come on; I had no problem and no apparent voltage drop that made any difference, using a bracket on the engine as the ground and the "positive" connection under the bonnet.
Jump-start using a Volvo V70? - defender
another good reason for connecting to a seperate earthing point on the flat battery car is that often a flat battery will soak up the power going through the jump leads causing the leads to heat due to too much power going through them
Jump-start using a Volvo V70? - Civic8
>>another good reason for connecting to a seperate earthing point on the flat battery car is that often a flat battery will soak up the power going through the jump leads causing the leads to heat due to too much power going through them

think you will find its to prevent surge setting off airbags,as for most jump leads are capable of staying in contact with battery and charging,mistake made on most flat bats are connecting direct.. then trying to start straight away.they need time to recover accepting the charge from another source-given time unless knackered should be able to recover..seen it many a time as no one has the patience to wait
--
Steve
Jump-start using a Volvo V70? - Cliff Pope
.they need time to recover accepting
the charge from another source-given time unless knackered should be able
to recover..seen it many a time as no one has the
patience to wait



That's a very good point - I never thought of that before. I've sometimes wondered about the wisdom of connecting 12+ volts to a battery whose voltage has just been temporarily flattened to maybe 6 or nil.
Jump-start using a Volvo V70? - Martin Wall
Sorry SjB - when you say "a bracket on the engine as the ground and the "positive" connection under the bonnet" - is this refeering to where you put the leads on your V70 or where you put the leads on the SAAB? Thanks...
Jump-start using a Volvo V70? - sierraman
I cannot understand why people keep churning when the battery is obviusly not giving enough power to start the car.Left my lights on the other day,car would not start,waited five mins.,made sure everything was off,car fired up straight away.Isn't connecting to the engine block not so easy these days with cars having a big chunk of plastic in the way?
Jump-start using a Volvo V70? - SjB {P}
Sorry SjB - when you say "a bracket on the engine
as the ground and the "positive" connection under the bonnet" -
is this refeering to where you put the leads on your
V70 or where you put the leads on the SAAB? Thanks...


Both.

With "normal" cars I do as written in a previous post.
With the V70 though there is no negative terminal from which to jump, so I use any good earthing point on the engine instead.

On the "flat battery car" I also use an earth point, not the battery negative terminal, for the spark reason given.
 

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