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Ask Lou P. master tech Your Own Question
Lou P. master tech
Lou P. master tech, Mercedes Technician
Category: Mercedes
Satisfied Customers: 4249
Experience:  15 years master certified 100% fix rate and have access to factory radio codes, wiring, and instructions.
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Def light is on but full def i drove it about 300 miles

Customer Question

def light is on but full def i drove it about 300 miles light can on iput about i gal in it and it was full when i left is that to much def light can on again top it off light still on i need to talk to some one on the phone not good on a pc
JA: Just to clarify, what are the exact lights you're talking about?
Customer: def and check engine
JA: What year is your 300?
Customer: 2013 mb with 13000 miles
JA: Are you fixing your 300 yourself? What have you tried so far?
Customer: full up with def light still on
JA: Anything else you want the mechanic to know before I connect you?
Customer: no
Submitted: 8 months ago.
Category: Mercedes
Expert:  Lou P. master tech replied 8 months ago.

Hello, my name is***** and i will do my best to assist you.I am going over your story now and will reply back soon with some info,thanks!

Expert:  Lou P. master tech replied 8 months ago.

is there a check engine light on or just a def light on?

Expert:  Lou P. master tech replied 8 months ago.

if there is NO check engine light on then try this,

get in the van and close the doors,

insert the key in the ignition and turn it from off to on 5 times fairly quickly, and then the light should go off, let me know if this works. Lou P.

Customer: replied 8 months ago.

check engine light on also def light

Expert:  Lou P. master tech replied 8 months ago.

ok, if there is a check engine light on then there is a issue with the level sensor or one of the heaters, you will need to take it to a sprinter dealer asap or you will get the 20 starts remaining warning and after the 20 starts the van will NOT start anymore. :(

there really is very very limited things a owner can do with the def system.

Expert:  Lou P. master tech replied 8 months ago.

if in the future you have a low def warning and NO check engine light then you can do the key trick to do a quick reset. hope this helps, again there is very very limited things anyone can do without the mercedes scan tool and access to germanys servers for the coding and resetting of the adblue system.

let me know if you have any more questions about this, Lou P.

Please take a second and click the STARS above and rate my service 4 or 5 stars if you feel I have been helpful and please request me in the future. Keep in mind that when you rate it does not end our conversation, you can still return here to me for follow up information if needed, Thanks for choosing just answer. Also , if you feel i deserve one , BONUSES are GREATLY APPRECIATED! Thanks again , Lou P.

Customer: replied 8 months ago.

did not work is my mb still in warrant i am the secon owner it has 14000 miles

Expert:  Lou P. master tech replied 8 months ago.

may i have your vin?

Customer: replied 8 months ago.

wd3pf4cc2c5690524

Expert:  Lou P. master tech replied 8 months ago.

i show the van was shipped may of 2014, is that when you purchased it?

Expert:  Lou P. master tech replied 8 months ago.

if so the warranty is only 3 years 36k miles, so no it will not be under warranty. unless you purchased it used and purchased a warranty with it.

Customer: replied 8 months ago.

how much do you think it will cost to fix it and if i am on the road and my mb guit will it restar are what do i do thanks

Expert:  Lou P. master tech replied 8 months ago.

if you are on the road when it quits then it will have to be towed. there will be nothing you can do . as for cost, it can be software update for 200$ or a level sensor which will run about 1100$ give or take, prices are hard for me since all dealers do NOT charge the same.

Customer: replied 8 months ago.

can a tech that has a pc fix in the little town that i live in

Expert:  Lou P. master tech replied 8 months ago.

eh, that is a hard question. it does depend on the fault code, so it can be possible if the fault code is just with a heater, or the level sensor, so the test would be to try to see if he can read the fault codes, then see if he can erase the fault codes, if he can erase them then he should be able to fix the issue and get the light off, the problem we run into is that most code scanners can read the codes so you can diagnose the issue and fix it BUT you cannot reset the light so the issue remains.

Expert:  Lou P. master tech replied 8 months ago.

let me know if you need more help or if the tech needs help with the codes

Please take a second and click the STARS above and rate my service 4 or 5 stars if you feel I have been helpful and please request me in the future. Keep in mind that when you rate it does not end our conversation, you can still return here to me for follow up information if needed, Thanks for choosing just answer. Also , if you feel i deserve one , BONUSES are GREATLY APPRECIATED! Thanks again , Lou P.

Customer: replied 8 months ago.

i am going to let a tech at a little grage here in town if he need code give me code and see if he can help it 80 miles to mb dealer thanks for you help

Customer: replied 8 months ago.

lou i did the five thing ouickey light went off it went so i drove it about 1 mile ok stop and fuel up the light con back on

Expert:  Lou P. master tech replied 8 months ago.

ok so to be clear the def light went off after the 5 key cycles and came back on?

Customer: replied 8 months ago.

yes it can back on is their anyway to delete this dam mess when i drove that 300 miles with it used 1/2 gallon so it working so well quit running

Expert:  Lou P. master tech replied 8 months ago.

There is a module that you can buy on ebay that simulates a system so the warning lights stay off. here is a link

http://www.ebay.com/itm/Adblue-Emulator-7-In-1-Module-Truck-Adblue-Remove-Tool-With-Programing-Adapter-/261541693326?hash=item3ce519878e:g:Dv4AAOSwRLZT0KG~&item=261541693326&vxp=mtr

Please take a second and click the stars at the top of the screen to rate me so i may receive my credit , 5 stars is ideal , please request me in the future.
Keep in mind then when you rate it does not end our conversation. you can still return here to me for follow up information if needed, Lou P.

Expert:  Lou P. master tech replied 8 months ago.

I have taken my time to answer your question the best i could and i will continue to help if you need follow up information , all i ask is that you PLEASE take a second to rate my service so i may receive my credit for assisting you. Thank you.