Preglow Indicator Lamp

arl

New member
I have a 2011 Sprinter.

I wonder if anyone can tell me how long the Preglow Indicator Lamp should stay on when the ignition is turned to position 2, especially when the engine is cold.

Thanks
 

arl

New member
Thanks for the response, Toskeysam. I thought perhaps mine did not work correctly since it routinely goes out after about 1 or 2 seconds. But I live in a very moderate climate.
 

KC8RXQ

2016 Thor Synergy TT24
I realize that this thread has been inactive but I am looking for some information anyway. We have a new 2016 Thor Synergy and I have yet to see the glow plug heater lamp illuminate in the dash display. The ambient temperatures had been in the 30's to low 40's but I haven't seen that light come on like my Ford Powerstroke would. Does the Mercedes design allow for a lower threshold temperature before the glow plug heaters come on or is this a repair item?

Thanks in advance for the help.

Ed/KC8RXQ
 

vonderlust

New member
I'm in a similar boat, wondering why my glow plug light isn't coming on - from what I've read, it's a repair item, so I'll be taking it in on Wednesday.
 

irvingj

2015 RT SS Agile (3.0L)
Just curious… are these Sprinters having any troubles starting? Do you wait a bit even though the glow light isn't on, or do you just hit start?
 

sailquik

Well-known member
The recommended protocols suggest that you turn the key to position 2 (where all the light on the dash console light up and then go out)
and wait a few seconds (regardless of temperature) for the little glow plug indicator light (it's a small coil) to go out.
As soon as the glow plug light goes out, you are ready to start.
When it's very cold, the glow plug light will stay on slightly longer.
You should never knowingly, just turn the key and start the engine unless the engine is already warmed up in which
case there is no glow plug light.
The glow plugs are an important part of the emissions package.
They ensure faster cold starting of the engine and they are used to increase combustion temperature during DPF
regenerations.
If you do not see the glow plug light when cold starting (even @ 60-70 degrees F) something may be wrong.
I believe the glow plugs are covered under the emissions warranty.
If they are not, they should be as they are required for DPF regeneration.
Hope this helps,
Roger
 

KC8RXQ

2016 Thor Synergy TT24
Roger,
Thank you for the explanation. I have yet to see the glow plug light come on and the temperatures have been cold to down-right frigid lately. I do wait several seconds before actually starting the engine in the hope that it's just the light that has the problem and not the glow plug system itself. I am making a list of things to present to the Mercedes Sprinter service advisor - when I can find one - and see water they find.

Regards to all!
 

sailquik

Well-known member
KC8RXQ,
Where are you located?
Are you sure the light isn't coming on?
Have a look at your Operator's Manual (Page 228) to see exactly where the little coil symbol is located.
It only comes on for 2-5 seconds, then goes out indicating that the glow plug system has cycled and all the glow
plugs are heated up to ~ 1,000 deg. C.
Here's a link to the BERU site that gives a lot of background information on glow plugs:
http://www.beru.com/download/produkte/TI04_en.pdf
Hope this helps,
Roger
 
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smiller

2008 View J (2007 NCV3 3500)
Right now it is about 35F outside and I just turned my key to the run position (engine off, cold soaked). All of the dash warning lights illuminated (bulb check, as normal) and the glow plug light went out after about one second. I don't think I've ever seen it take longer than a second or maybe two to go out no matter how cold it is (lowest I've been in is perhaps the low 20s). Is this normal? I have no codes and the engine always willingly fires up within a few cranks at most, and runs smoothly immediately after the start. It's hard to believe there's anything wrong, in fact I've always thought that the cold weather manners of this engine (V6) is better than any other diesel I've owned.

.
 
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sailquik

Well-known member
smiller,
Perfectly normal.
According to the BERU link I posted above, the entire glow plug cycle takes 2-5 seconds.
So, you turn the key, and by the time you've focused on the glow plug symbol, some of that
2-5 seconds is already gone.
If your battery has full voltage available, the entire glow plug cycle is just the blink of an eye.
About the time you see it, it will go out.
When the battery voltage is low, it may take longer for the glow plugs to cycle, and it may take a while
longer for the engine to start since it will not spin over on the starter as fast.
Hope this helps,
Roger
 

KC8RXQ

2016 Thor Synergy TT24
Sailquick,

I'm located East of Beckley, WV.

I went to the vehicle again and turned the key to position 2 and low-and-behold the glow plug light flashed on for 1-2 seconds and then was gone. That was with the ambient temperature at 20°F so I have learned something new for sure. I own a Ford F350 with the 6.4L Powerstroke diesel engine and I'm used to seeing the glow plug light stay on for 5-10 seconds in temperatures like this. I really had no clue that the Sprinter would heat up that fast.

So, thanks for the help and now it's on to a couple of other - minor things like the lack of backlight illumination for the headlight selector switch, and the cold air that is blowing in around the radio and through the joints in the dashboard. Other than those two minor items I am pleased with my new purchase and hope to find a good Sprinter service shop that I can go to for warranty and service.

Thanks!
 

220629

Well-known member
As has been stated, the glow plugs are used for emissions smoke reduction for every start, and for DPF regeneration. For cold weather/cold engine starts the T1N glow plug cycle doesn't kick in until 32F. So at all other times the glow coil will be on very briefly. It should be basically the same for newer models.

155GlowPlugs.jpg

WTS = Wait to Start

156GlowPlugs.jpg

157GlowPlugs.jpg

:2cents: vic
 

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