Jump starting other car

[SimplyMB]

The battery on my wife's Hyundai Santa Fe died. Is it safe to jump start it using my 2011 S212 as booster car? Really don't want to get any electrical faults afterwards.

 

[skippyjasper]

Would not be my first choice, but if there was no other way here’s how I’d accomplish it.

Maneuver the booster car to a spot when the cables will reach.

Turn the booster car off and put the key in your pocket.

Connect the two cars and attempt to start the car needing the boost.

Only restart the booster car after removing the cables.


Sent from my iPad using Tapatalk

 

[Justintyme]

Normally, when I'm jump starting ( or boosting ) a car with a flat battery, the routine I use is: Leave donor car engine running. Lift both both bonnets. Connect Negative to Negative with the black jumper lead first, and then the positive red lead from the donor car to recipient. Wait a minute or two, then start flat battery car. After it start's, remove the black negative lead from the donor first, and then from the recipient ( obviously not allowing the two leads to come into contact with each other ) Then remove the Red lead...job done.
You mention in your post that the donor car should be switched off, and only then connect the jump lead's. As I have never either had to use my w212 to jump another car, or has it needed to be jumped itself ( touch wood).I presume that your way is the accepted MB approved method?
Thanks for the post.

 

[mikrt]

I was always told blacks on last & off first.

 

[optimusprime]

Dead right earth off first replace last . But never star another car with mine.. .Thats me ..

 

[renault12ts]

My routine. Connect both cars...red on first, black off first.

Start donor car engine, then start flat car.

 

[Chugg]

- Do not connect cables with the cars running, unless you want to risk a surge or short circuit.
- Always connect positive/red first, unless you again want to risk a short circuit and blowing fuses/melting things.
- Do not connect the negative/black to the bad battery, unless you want to see sparks and risk a hydrogen gas out/explosion. Always connect to an unpainted part of the body.

Just go:
Ignitions off.
Red/+ on the bad cars battery.
Red/+ on the good cars battery.
Black/- on the good cars battery.
Black/- on unpainted part of the bad cars body.
Start the good cars engine and let it run for 5 mins.
Remove cables in reverse order.
Keep the bad battery car running for about 20-30 mins to make sure it gets enough charge by itself.

Have a brew, then get the wife off to work.
Job done.

 

[m80]

Engine off.
Connect +ve first, that reduces the chance of it arcing (shorting) if it touches the chassis (or engine) while connecting it.
Still engine off.
Allow a few minutes for the energy to transfer from healthy battery to flat battery.
Still engine off.
Try to start the flat car.
If that fails (as it might with poor leads or large diesel engine) then try to do the same with the engine of the donor car running.

As the donor car will put out over 14 volts with the engine running it reduces risk of any surge with the engine off.
Poor quality jump leads will struggle to allow the energy to transfer so if an 'engine off' jump fails it may work better with the donor engine running (and so a higher voltage at source).

Poor, cheap jump leads can make this job a pain.

 

[Chugg]

Start the good cars engine and let it run for 5 mins.

After that bit I should of put:
Then start up the dead car

And like m80 says good leads with chunky cables are a must. Don’t even bother with cheapos with cables like spaghetti.
Having the jump car not running while attempting to start the dead car is a bit of a moot, and preference really. If you don’t have it running, you risk ending up with two dead cars if the first dead un needs a bit of persuading back into life, as you’ll have no alternating current coming in to charge either battery. It does however reduce the risk of surge, but a Santa Fe should easily be able to handle the +-14v from the jump car. Just put the rear de mister and lights etc on to dissipate any surge, which would result in a bit longer recovery times.

 

[m80]

as you’ll have no alternating current coming in to charge either battery

I guess you mean current from the alternator?

It was fairly common for earlier MB's to fry SAMs during jump starts, but I've not heard that for a while.
But with all the delicate electickery in today's mo mo's I still prefer to avoid the possibility of surge currents.

 

[Chugg]

I guess you mean current from the alternator?

It was fairly common for earlier MB's to fry SAMs during jump starts, but I've not heard that for a while.
But with all the delicate electickery in today's mo mo's I still prefer to avoid the possibility of surge currents.

Yes, good guess! Alternating current is current from the alternator.

I hear you re being cautious.

 

[pmcgsmurf]

Yes, good guess! Alternating current is current from the alternator.

I think the point was no it is not.

 

[Chugg]

I think the point was no it is not.

Not what?
I maybe misunderstanding you here though!
An alternator uses mechanical energy and changes it to electrical energy in the form of alternating current.
If ‘ it is not’, what is ‘it’ then?

 

[markmifsud]

Not what?
I maybe misunderstanding you here though!
An alternator uses mechanical energy and changes it to electrical energy in the form of alternating current.
If ‘ it is not’, what is ‘it’ then?

The alternator produces AC as above but has a diode bridge rectifier before the output terminals so that the output is a controlled DC

 

[pmcgsmurf]

Not what?
I maybe misunderstanding you here though!
An alternator uses mechanical energy and changes it to electrical energy in the form of alternating current.
If ‘ it is not’, what is ‘it’ then?

Direct Current.

 

[Chugg]

The alternator produces AC as above but has a diode bridge rectifier before the output terminals so that the output is a controlled DC

This^

 

[Chugg]

We’re maybe going a bit far here, the op has probably jumped it off and had two days driving around by now

From Wikipedia (that’s never wrong is it?!?):

‘An alternator is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current.[2]’

 

[m80]

I guess we can all agree on that then, AC to DC.

 

[Chugg]

I wouldn’t mind, I was a victim of misspelling and autocorrect!! I simply meant alternator current not alternating

 

[m80]

I wouldn’t mind, I was a victim of misspelling and autocorrect!! I simply meant alternator current not alternating

Blurry computters.