PDA

View Full Version : Glow plug light staying on,,, help!


jim Camp
08-08-2013, 02:13 AM
New to sprinters I purchased an 03- 5 cylinder truck and the Light comes on when you turn the key, then goes off ,,,when It starts it stays off for about 2-3 seconds then come on and stays on, starts good and runs good? Then after it runs for a while ,,mabe a few hours the light goes off?some times its off after it starts!any ideas?

riskydnb
08-08-2013, 02:25 AM
New to sprinters I purchased an 03- 5 cylinder truck and the Light comes on when you turn the key, then goes off ,,,when It starts it stays off for about 2-3 seconds then come on and stays on, starts good and runs good? Then after it runs for a while ,,mabe a few hours the light goes off?some times its off after it starts!any ideas?

You may either need glow plugs or a glow plug relay or both. Does the check engine light come on? If so scan the codes and it should tell you what cylinder glow plugs are bad and if the relay is bad. If you need them, I sell them cheaper than anyone online. PM, call or text me @ 760.622.0148 -Randy

surlyoldbill
08-08-2013, 03:11 AM
Stored code makes the light pop back on after starting.
Glow plugs are ONLY activated for starting, they have no relationship to the motor running once started. If you are in a warm climate, you may not even need good glowplugs to start. I was able to start with only 3 good ones after staying overnight in the mountains where the temps dropped down to single digits; but barely started after ten minutes of trying.

Does the light go off once you reach operating temp of 180, or do you mean that it stays off the next time you start once the motor is warm?

riskydnb
08-08-2013, 03:58 AM
Stored code makes the light pop back on after starting.
Glow plugs are ONLY activated for starting, they have no relationship to the motor running once started. If you are in a warm climate, you may not even need good glowplugs to start. I was able to start with only 3 good ones after staying overnight in the mountains where the temps dropped down to single digits; but barely started after ten minutes of trying.

Does the light go off once you reach operating temp of 180, or do you mean that it stays off the next time you start once the motor is warm?

Ya clear any codes, drive a bit and see if they come back or if your symptoms come back.

nathanhdunn
08-08-2013, 04:45 AM
I can confirm you don't need glowplugs in warm areas, I've got 4/5 dead glowplugs (according to a computer read) and it starts first go, even when there was frost on the ground (about as cold as it gets where I live)

Glowplug light stays on for 60sec precisely, and was told this means there are faulty plugs, but the control relay is ok.

riskydnb
08-08-2013, 06:05 AM
I can confirm you don't need glowplugs in warm areas, I've got 4/5 dead glowplugs (according to a computer read) and it starts first go, even when there was frost on the ground (about as cold as it gets where I live)

Glowplug light stays on for 60sec precisely, and was told this means there are faulty plugs, but the control relay is ok.

True, but the issue of not fixing the glow plugs which causes the check engine light to be on could cause MAJOR damage to your vehicle because you are assuming the light is on cause of the glow plugs but in reality the truck could be overheating or some other major engine warning could be going on. It may cost you the price of a new engine to save $400 on doing the glow plugs.

nathanhdunn
08-08-2013, 06:11 AM
My check engine light isn't on, if yours is, perhaps there's something more than the glow plugs?

riskydnb
08-08-2013, 06:40 AM
My check engine light isn't on, if yours is, perhaps there's something more than the glow plugs?

No I work on a fleet of sprinters, I come across the check engine light being on cause of the glow plugs daily.

nathanhdunn
08-08-2013, 06:57 AM
Then, Risky, we're left with 2 options, perhaps there's 2 or more failure modes for the glowplugs, some of which turn on the check engine light and some dont, or my check engine light is broken...

I hope it's not the second, like you said, that could lead to a whole lot of pain

Edit, also, you might be talking about NCV's, I'm in a T1N

bruceiam
08-08-2013, 11:35 AM
My glow plug light acts like the OP's, comes on at key on, goes off, I start and occasionally comes back on after start, usually doesn't stay on for a long period of time after start. The check engine light doesn't come on but it always stores glow plug codes. My van is a Freightline, 2002. Also, as far as I know, the check engine light only comes on for emission related faults.

surlyoldbill
08-08-2013, 03:47 PM
Remember the old style module/relay blows internal fuses when a glowplug shorts to ground or draws too much current. Previously that meant you had to but a new $$$ module everytime a glowplug went bad. The new style resets itself, like automatic circuit breakers. If you have the old style the glow plug will still not work even if new, and a code will be stored.

I've posted this many times before, but sometimes both the module and the glowplugs are perfectly fine (or were, in the case of the module...). The wire loom containing the glowplug wires can be abraided on the steel brake lines or other parts and shorts to ground. Inspect every inch of the wire harness coming from the module.

indigoE
08-08-2013, 04:44 PM
2003 Passenger van

Last year, I had the glow plug dash-light come on one day. Drove all the way across Pennsylvania ( all day) with the glow plug light on. When I stopped that evening, the battery was dead as a door-nail. The glow plug relay was at fault, and the battery needed replacing. So I would suggest you check the relay, as it will drain the battery.

tphilly
08-08-2013, 09:04 PM
My glow plug light comes on once it has started for around 45seconds. Now it's struggling to start. have changed glow plugs and relay. it's a 2006 311cdi.

indigoE
08-09-2013, 06:31 PM
Remember the old style module/relay blows internal fuses when a glowplug shorts to ground or draws too much current. Previously that meant you had to but a new $$$ module everytime a glowplug went bad. The new style resets itself, like automatic circuit breakers. If you have the old style the glow plug will still not work even if new, and a code will be stored.

I've posted this many times before, but sometimes both the module and the glowplugs are perfectly fine (or were, in the case of the module...). The wire loom containing the glowplug wires can be abraided on the steel brake lines or other parts and shorts to ground. Inspect every inch of the wire harness coming from the module.

Question for surlyoldbill: Is the re-settable glow plug relay an after-market part? Is it available from places like Europarts?

tphilly
08-09-2013, 10:02 PM
Couldn't get one from eurocarparts when I changed mine. Got a genuine one from Mercedes for cheaper than I could find on ebay

Sent from my GT-I9305 using Tapatalk 2

surlyoldbill
08-10-2013, 12:08 AM
Question for surlyoldbill: Is the re-settable glow plug relay an after-market part? Is it available from places like Europarts?

They are the new Mercedes ones.

indigoE
08-10-2013, 06:13 PM
They are the new Mercedes ones.

Perhaps Freightliner installed the new MB module. Can you tell if this is the re-settable module?

surlyoldbill
08-10-2013, 09:04 PM
Perhaps Freightliner installed the new MB module. Can you tell if this is the re-settable module?

YES.
It is thinner front to back than the original module model.

autostaretx
08-10-2013, 09:29 PM
Extrapolating wildly from the markings on the photograph, that unit was built in the first week of 2012
using the hardware design of the 33rd week of 2009, and the firmware last updated/released in the 44th week of 2009.

--dick

indigoE
08-12-2013, 09:24 PM
YES.
It is thinner front to back than the original module model.

So the next time the glow plug light stays on ( hopefully never again), I would check to see if the module needs re-setting. How is the re-setting done?

surlyoldbill
08-13-2013, 02:28 AM
It resets itself automatically, probably with re-start of engine.

hppyfngy
08-24-2013, 10:17 PM
I just started experiencing something like this. Turn key to on, wait for glow light indicator to go out, start engine, indicator goes off and then seconds later comes back on again.

But it's intermittent and doesn't even have the same behavior each time. Sometimes it will stay on for several minutes and then I notice it's gone off again.

A couple of times, I swear I turned the key and the indicator light didn't come on. Or did I imagine that? Where is the module on my '03 T1N, please?

Randy

autostaretx
08-25-2013, 01:11 AM
Where is the module on my '03 T1N, please?
Probably under the front of the battery, as shown here:

54214

(image grabbed from 2003 or 2006 Service Manual (end of section 8w), available from http://aie-services-2.net/Sprinter/ )
--dick

hppyfngy
08-27-2013, 05:06 PM
So, tell me. I am having no symptoms except for the irregularity of the glow plug indicator coming back on sometimes. But I have business that means I need to take off for about an 800 mile round trip.

Am I okay to do that before I investigate this further? I need to take the van but don't have time to check it out first.

surlyoldbill
08-27-2013, 10:23 PM
Randy, you're fine.
The glowplugs are only used for starting, and only in cold to cool weather. A bad glowplug or three has ZERO impact on your motor once it is started.
I started my van on 3 working GPs after camping in 12-17 degree temps all night. It took a lot of attempts, though.

hppyfngy
08-28-2013, 10:17 AM
Thanks Bill,
I'm having no problem starting or running so I'll check things out after my trip.
Appreciate it. :)