What does this dash light mean?

[brobox]

Originally Posted by oneknight

That light is not anything to do with DEF.

It is DPF regen in progress.
Drive it like you stole it til the light goes out, could be as much as an hour.
Normal operation on a modern emissions controlled diesel

For my own learning situation, I have never experience it....why would the light on the OP's dash that he pictured be the low DEF light and not one of the regeneration lights on all of the Spartan charts? Yet his light had nothing to do with low DEF? That one is confusing the hell out of me.

[Dieselgem]

Chuck,



I think the reply's have been confusing. The light I see is a particle filter regeneration light. It comes on when high temperature are required to clean the DEF filter. Driving the vehicle at highway speeds will clear the code once the filter is clean. It is not advisable to stop and start when possible during the regeneration. The DEF itself is used naturally during the process.

[Mwoodofd]

I'm confused too. The light in the OP dash image, and the chart that Chuck provided a link to is labeled a Low DEF light. It may be wired wrong, or the wrong warning light is installed in the dash, or the chart is wrong.

It appears that it was a regen situation since the tank was half full, and the light went out after driving, but something is not correct in the dash light or documentation.

If that warning light is used for both instances, maybe some of the lights in the dash are not lighting correctly?

[Dieselgem]

When I blow up his photo it is not the low DEF symbol. The low DEF symbol has an additional symbol to the side of it.

[Dieselgem]

I have never checked to see if the coach show exhaust temps. That is the easiest way to see if it is in regen mode. I had them in an f450 and you could see the temp rise.

[brobox]

Originally Posted by Mwoodofd

I'm confused too. The light in the OP dash image, and the chart that Chuck provided a link to is labeled a Low DEF light. It may be wired wrong, or the wrong warning light is installed in the dash, or the chart is wrong.

It appears that it was a regen situation since the tank was half full, and the light went out after driving, but something is not correct in the dash light or documentation.

If that warning light is used for both instances, maybe some of the lights in the dash are not lighting correctly?

Mark you are seeing the same thing I am. The Spartan Chart I found and the one Stu posted both show that light to be Low DEF. I have looked at all 3 DEF lights over and over, the photo in the OP is low DEF. Like you the only conclusion I could come up with is wrong dash light or wrong wiring.

Thank you for letting me know I am not totally nuts yet.

[brobox]

Originally Posted by Dieselgem

When I blow up his photo it is not the low DEF symbol. The low DEF symbol has an additional symbol to the side of it.

BINGO!!! But the OP reported that it preformed as a regen light, yet it is the low DEF light.

[Dieselgem]

Originally Posted by brobox

BINGO!!! But the OP reported that it preformed as a regen light, yet it is the low DEF light.

Chuck, I would bet think they used one light for both. When it throws a code either part or the whole lights up.

[brobox]

Originally Posted by Dieselgem

Chuck, I would bet think they used one light for both. When it throws a code either part or the whole lights up.

That could be correct, but why does Spartan show 3 different lights on their charts. Without turning the OP's key on to see what the dash lights are, we can't do it from a post.

[DeeGee]

Originally Posted by Tom78418

Looking at you photo there is no indication of the DEF tank level showing. Possibly the indication didn’t show in the photo. At risk of covering something you already know DEF is a “on the side of the road” show stopper. The gauge goes from green bars, to one green bar (best find some DEF soon), one yellow (you’re running very low, go to the nearest truck stop or Walmart), one red bar (too late, you’re engine is about to derate, coach slow to limp mode, and don’t shut the engine off as it won’t restart).

From the manual:

1 bar out of the 4, in green: DEF level is 10% to 25%

1 bar, yellow - DEF 2.5% to 10%. This is accompanied by chime (5 sec), DEF warning lamp and LOW DIESEL EXHAUST FLUID message on LCD.

1 bar, red - DEF 0% to 2.5%. DEF warning lamp on. Check Engine lamp on. Audible warning, steady tone. LCD says ENGINE DERATED - DEF LOW. The engine gets a 25% torque derate.

1 bar, red, flashing - DEF 0%. DEF Warning lamp flashing. Check Engine lamp on. Audible warning, steady tone. LCD reads ENGINE DERATED - DEF EMPTY. 40% torque derate.

1 red, flashing - DEF 0%. DEF Warning lamp flashing. Check Engine lamp on. Stop Engine lamp on. Audible warning, steady tone. LCD reads SPEED RESTRICTED - DEF EMPTY. Engine restrictions: 5 mph speed limit. 40% torque derate. 1100 RPM limit. This level is triggered when the DEF level is 0 and one of the following conditions is met:
a) the engine is turned off and restarted
b) engine is allowed to idel for one hour
c) fuel tank is refilled without refilling DEF.

So, don't let it happen!

[777 Driver]

Originally Posted by Mwoodofd

I'm confused too. The light in the OP dash image, and the chart that Chuck provided a link to is labeled a Low DEF light.

Originally Posted by brobox

Mark you are seeing the same thing I am. The Spartan Chart I found and the one Stu posted both show that light to be Low DEF.

The OP's photo (with my annotation):


You'll note that the light is immediately adjacent to the lower left corner of the Message Center.

From the link Chuck provided:



You'll note that it is the Diesel Exhaust Fluid Low light in that same location as the OP's illuminated light.



It just really doesn't make sense that the DEF quantity level did NOT indicate low and that the DEF low light cleared without adding DEF.

I share your confusion.

The only possible explanation that I can come up with, which is pure speculation, is that there are separate DEF quantity sensors. One set of sensors that show the quantity of DEF in the tank that are wired to the tank quantity indicator AND a separate sensor that is only used for the DEF low light indicator. That sensor was incorrectly sensing low quantity which erroneously turned on the light. Driving a short distance, with sloshing DEF in the tank, reset that sensor and the light turned off.

I really don't believe that the OP experienced a DPF regeneration cycle.

I may be wrong...but...I really doubt it as I've NEVER been wrong before.

Take care,
Stu

[brobox]

Stu, you explained as only a pilot could, and very well!! I just saw it as the guy that kept you guys flying. Tech manuals don't lie, I would think the same for Spartan Manuals. However when I was wrenching we didn't have lights that confused everybody. We had gauges and you had to know how to read a tech manual. Looks like those days are gone and probably why I still do most to my own work. I can still read a tech manual.

[Tom78418]

There are 3 common lights associated with DEF. Sorry, but he indicator in the photo is for low DEF. the DEP light has an icon of a filter across the DEF icon. If you are getting a DEF light and you still have a half tank, you should get it checked. There are enough bad tales of those with DEF level gauges causing problems. Derated to 10 mph for a level sender would be annoying to say the least

[brobox]

Originally Posted by Tom78418

There are 3 common lights associated with DEF. Sorry, but he indicator in the photo is for low DEF. the DEP light has an icon of a filter across the DEF icon. If you are getting a DEF light and you still have a half tank, you should get it checked. There are enough bad tales of those with DEF level gauges causing problems. Derated to 10 mph for a level sender would be annoying to say the least

Tom, I have to agree, if the low DEF light is coming on with no error codes, what is causing it? Is one of the DEF sensor going bad that may quit in the middle of UT? If nothing else, hopefully others are seeing it is important to see what the idiot lights are really saying and not take to quick of a look saying it "will be alright in an hour". There is a few darn good mechanics here that read the OP light wrong. Any of the DEF lights coming on while running down the road are of concern.