Spinter tries to start itself with no keys in ignition

jonboothx

New member
Hi all

New to the group, bought a 2014 MWB sprinter 2 months ago to convert in to a camper.

The battery was a little weak so charged it via the jump start terminals this morning. Battery charger said it was connected to battery and left it to do its thing

3 hours later, the van starter motor begins to turn along with the windscreen wipers and the windscreen washer jets.

Put key into ignition and tried to turn ignition on and off but with no avail, starter motor continued

Couldn't stop the starter from turning the engine so disconnected battery (around 3 or 4 mins had elapsed at this point), strong smell of burning cables and dead battery (and possibly starter motor too)

All electric appear to be OEM, no hacking of new cables anywhere that i can see

Anyone got any idea where to start with this ? Checked and it appears as though the relay is on the side of the starter but if there was no key in the ignition, would the cable that feeds the relay be powered at that point ?

Any help appreciated... partner v upset

Thanks in advance

Jon
 

sprint2freedom

2008 NCV3 170ext
Unlike many/most other vehicles, the starter is controlled by the ECU, not the ignition switch. This is apparent when you turn the key because you don't need to hold it in the "start" position for it to continue cranking.

But, it sounds like your problem might be caused by a starter solenoid that's stuck "on"? Although that doesn't explain why it began cranking in the first place..

Because of the high current draw of the starter, the solenoid delivers power directly from the battery (independent of the ignition key).
 
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Rob S

2008 Navion J on 2007 V6
Is it conceivable the solenoid remained engaged on last previous start attempt, and the starter just failed to turn due to low battery?

Then after charger was applied and the charge built up enough, it began to crank again?

You would think, being stuck on, it would have drained off any attempt to recharge, but who knows how the computer works in such case.

Definitely first thing to try is to remove and test solenoid, or most likely easier just replace entire starter assembly.

As to the "partner v upset", I have no idea what parts to replace or what to lubricate for those situations. Anyone knowing that could do very well for themselves. :)
 

jonboothx

New member
Thanks for your responses ... its appreciated..... Would that explain the windscreen wipers and the jet sprays ?

Ive checked all the fuse boards in case of water ingress but the 2 i can find are dry (one under drivers seat and one in passenger footwell)... uk so right hand drive btw

The only update i can think is that after removing the battery, putting a charge in to it, putting the battery back in the van and connecting each leg at a time, i have windscreen wipers (with ignition off) on 2 of the battery spur cables ???

From what i can gather, the fuse board under the passengers (left hand side as your sat in it) is fed from one leg so why would windscreen wipers work on 2 (think windscreen wipers are on the fuse board under the passengers side)

Any further ideas ladies and gents would be appreciated
 

Aqua Puttana

Poly - Thread Finder
My thoughts would go to what changed.

Connecting the battery charger to the remote terminals is one change. It could be possible that some cable or component overheated and shorted together during, or as a result of, the charging operation. The wipers coming on symptom makes that a bit of a long shot, but worth considering.

Inspect the steering column, MFS, ignition switch for signs of liquid intrusion. It wouldn't be the first time that coffee, water, soda, or some other beverage was spilled into the steering column. Even if that happened in the past it could take some time for any effects to reveal themselves.

:2cents: vic
 

sparkplug

Active member
I don't know whether to suggest an auto electrician or an exorcist!

Assuming you don't have the wipers switched on at the stalk then I can only assume that there's either a short or something going on with a faulty earth or a fried ECU of some sort.

What does your earth strap look like?
 

Old Crows

Calypso 2014 View Profile
He!He!He! Sorry Bud.... you have reminded me of the Old Man's '57 Studebaker Golden Hawk. It became possessed after a couple years in Biloxi MS. Had to make sure the park brake was on and it was always in NEUTRAL when parked. It would spontaneously start and run for awhile and then shut down. Might not do it for a couple months. Then do it every other day. Then nothing..... for a week. It was possessed or inhabited by the Wee People, Fairies, Goblins or Gremlins. Finally, the starter solenoid was identified as the culprit. So I suggest replacing the solenoid as a start point.
 

jonboothx

New member
My thoughts would go to what changed.

Connecting the battery charger to the remote terminals is one change. It could be possible that some cable or component overheated and shorted together during, or as a result of, the charging operation. The wipers coming on symptom makes that a bit of a long shot, but worth considering.

Inspect the steering column, MFS, ignition switch for signs of liquid intrusion. It wouldn't be the first time that coffee, water, soda, or some other beverage was spilled into the steering column. Even if that happened in the past it could take some time for the effects to take hold.

:2cents: vic
Ill do that first thing
 

jonboothx

New member
Benz states in their manual not to connect a charger via booster ( jump start ) connection.
Do you know what, i asked my partner to look on youtube for how to charge the battery and she said everyone did it off the jump starter connections (after the fact)... so what have i fried ? Main ECU ?
 

jonboothx

New member
I don't know whether to suggest an auto electrician or an exorcist!

Assuming you don't have the wipers switched on at the stalk then I can only assume that there's either a short or something going on with a faulty earth or a fried ECU of some sort.

What does your earth strap look like?
Take the panels off and it all look like new, no rust anywhere, ill have a look at the earthing strap tomorrow
 

sparkplug

Active member
Thinking about it, the big red positive jump start post cable connects to the starter motor directly (on the same terminal as the 'Y' cable IIRC)

So, it could be as simple as the starter solenoid. No idea how you would test for that.

My knowledge is very minimal when it comes to electrics so I'm throwing ideas out there as much for other people to tell me I'm wrong as I am as suggestions to you - but I wonder if it's maybe the starter relay.

I have no idea how and if the relay or the starter solenoid could influence any of the wiper stuff though. That's a complete mystery to me.
 

pfflyer

Well-known member
Do you know what, i asked my partner to look on youtube for how to charge the battery and she said everyone did it off the jump starter connections (after the fact)... so what have i fried ? Main ECU ?
I did not know that either but I used a low amp battery tender connected to the jump start connectors for months to keep the starter battery topped off and nothing fried. I got the idea here and no one brought up that the manual says not to. Others here have done it as well. I guess I need to check my manual but I see no reason why that would fry anything.
 

Aqua Puttana

Poly - Thread Finder
... Others here have done it as well. I guess I need to check my manual but I see no reason why that would fry anything.
My guess is that the concern is with high amp chargers. The cable to the remote jump terminals is likely sized based upon the expected short time jump start service. A small(er) cable will not overheat for a heavy load over short time, but may may with a even a lighter load over long(er) time.

I agree that the typical household charger is not a problem. 15 - 20 amps is a common output on high setting. Most times that tapers off fairly quickly. Some service station chargers can output 40 or 200 amps.

:2cents: vic

Added:
See also Autostaretx Dick's post #18 regarding the Negative Isolation Switch.
 
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Bobnoxious

GONE FISHING

Bobnoxious

GONE FISHING
What was this vehicles prior life, anything to do with refrigeration?
 

EBH

Member
I'm reading this in my 2017 Sprinter manual.
I don't recall what my 2007 sprinter Manual read, but some where I did see the warning.
I have also charged via the jumper connection , but with my 2017 unit I charge directly to the battery or the 12 volt plug under the centre console .
Ed
 

autostaretx

Erratic Member
Also: what was the state of the main disconnect? (the black cable connection near the "gas" pedal)

If that was disconnected (the quickest way to kill all power), then your charger may have been trying to find sneaky ways to reach things
(where, pray tell, was your Negative Charging clamp connected???)
You may have been powering the whole thing through the charger.

Sprinters are *not* "do it as YouTube suggests ... and walk away" vehicles.

The main disconnect:
BattDisconnect.png

--dick
 

jonboothx

New member
What was this vehicles prior life, anything to do with refrigeration?
Hi Bob, not refrigeration, tyre van....looking through the manual it gives a max voltage of 14.6 for charging via the jump terminals and then in big black letter IT MAY DAMAGE YOUR VEHICLE !

Ive read some other posts on the forum about the jumper points connected straight to the starter but ive got continuity between the jump posts and the battery terminal so im guessing thats only in certain markets.... with my 19 yo charger on trickle (which is what it was on during the cycle) its doing 14v but i guess it wont be regulated the same way a power supply is.. 15 / 16 volts could be a reality !
 

jonboothx

New member
Also: what was the state of the main disconnect? (the black cable connection near the "gas" pedal)

If that was disconnected (the quickest way to kill all power), then your charger may have been trying to find sneaky ways to reach things
(where, pray tell, was your Negative Charging clamp connected???)
You may have been powering the whole thing through the charger.

Sprinters are *not* "do it as YouTube suggests ... and walk away" vehicles.

The main disconnect:
View attachment 155490

--dick
Didnt even know it existed .... im guessing its switched on as i drove the van the van 2 days ago ... im guessing this thread will turn in to 'how to fix it' thread......
 

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