2013 ML350 BT - P20B9 check engine light and def fluid pump nozzle broke

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Nov 21, 2019 | 12:34 PM
  #26  
You are right and even I am fully aware of. I am ready with all my research for where to buy parts and DIY for replacing the DEF tank heater. In my case, I purchased from a used car dealer in Milton - One price Auto (belongs to JP Motor Burlington). I will not trust the dealer to fix it by replacing brand new heater. In your opinion, what do you think the dealer Technician will do to temporarily delete the fault code which may come back in next 500 kms or may be the next time temp drops below Ad Blue's freezing point?
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Nov 21, 2019 | 02:04 PM
  #27  
Quote: You are right and even I am fully aware of. I am ready with all my research for where to buy parts and DIY for replacing the DEF tank heater. In my case, I purchased from a used car dealer in Milton - One price Auto (belongs to JP Motor Burlington). I will not trust the dealer to fix it by replacing brand new heater. In your opinion, what do you think the dealer Technician will do to temporarily delete the fault code which may come back in next 500 kms or may be the next time temp drops below Ad Blue's freezing point?
You bought a used DEF tank heater? That's the very definition of throwing money away. If you can't (or don't want to) buy a new one from MB, you only other - and quite possibly smarter - feasible choice is to get a Xemodex unit.

Whether the tech clears the code is irrelevant. The code will keep coming back until you repalce the heater.
Reply 0
Nov 21, 2019 | 03:28 PM
  #28  
No, I never said I bought used parts. I bought used Truck from the used car dealership (not CPO). After owing it on 2nd day cold morning the MIL lit up with P20BE and then I returned the truck to the dealer. I am glad to know that if the code is going to come back, then the dealer will have no other option - either to fix or keep the truck I will reverse the transaction = traded 2016 Ford Edge Titanium Pearl White FWD 2.0 Ecoboost 97,000 kms.
Reply 0
Nov 22, 2019 | 08:14 AM
  #29  
Ah - understood. Yes, the DEF tank heaters crap out from freezing / thawing cycles. If there is a warranty on the ML purchase and they pay for the repair, you're golden... that is pretty much the only thing that is known to regularly fail and is over $2K from MB (the NOX sensors also go but not quite as often on average). A new one should last you for a number of years.
Reply 0
Jan 27, 2020 | 01:13 AM
  #30  
Quote: +1 on the Xemodex DEF pump & heater rebuilds. No personal experience but I've heard only positive feedback from folks that are using them (and I know a bunch).
Hi Folks, my ML350 got code P20BE, proceeded to change the Xemodex heater unit, delete the code and the ML350 seems run fine for one day. Then code P20E8 showed up. What will be the best thing to do now? replacing the DEF pump? Any suggestion is highly appreciated. Thanks.
Saw in several threads that this P20E8 issue being discussed, but seems no clear answer to this. May have to bring to the dealership? any thoughts? Thanks.
Reply 0
Jan 27, 2020 | 09:49 AM
  #31  
It could be a number of things, although if you just replaced the heater unit yourself, my bet would be on an air leak in your newly assembled DEF tank or corroded electrical contacts. Paying the dealership to diagnose and/or fix it at this point is IMHO reasonable.
Reply 0
Jan 27, 2020 | 09:30 PM
  #32  
Thanks, Diabolis, because the P20E8 code wasn't there before, my best guess is that the crystalized urea plugged somewhere inside the pump during installation (someone in other thread discussed this possibility), although the pump nozzle was sealed during the process to prevent this from happening, it was still noticed that there are quite some crystal formed around the nozzle. If this is true, it may be possible to get rid of the P20E8 code through replacing the pump. Kind of don't know what to do know. Thank you for your comment.
Reply 0
Jan 27, 2020 | 11:52 PM
  #33  
RiverX - the nozzle needs to be capped to protect the DEF fluid, which crystallizes very easily when exposed to air. However, ammonia crystals rapidly dissolve in water, so you could try soaking it in water for a few minutes and then rinsing it out with some distilled water - assuming that the pump has not been damaged in the process, which is quite possible if it was running on empty or while the system was clogged. Given the relatively large number of possibilities at this point however, I would probably take it to an MB mechanic and at the very least let them diagnose the issue.

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Mar 2, 2020 | 12:27 AM
  #34  
Got the problem fixed?
Hey RiverX.

Did you fixed your issue with P20E8?

I’ve got the same problem.

Reply 0
Mar 3, 2020 | 01:58 AM
  #35  
I reinstalled the pump and found there was a little bit damage on the small o-ring of the AdBlue pump, but it seems that's not really the reason for P20E8 code since the damage is only a tiny scratch. There wasn't any crystal plug. The temp. was -15 degree C that day, which may cause this o-ring damage problem.
After the re-installation, erased the code, but it came back again within a day, with roughly 2/3 of the tank filled. Then I top-off the adblue, erased the code again. Then the P20E8 has stayed off.

So far seems fine but the I/M readiness of CAT and HRT is still in red. Anyone knows what is the Drive Cycle Test of ML350 Bluetec to reach I/M readiness? Thanks guys.
Reply 0
Dec 1, 2020 | 02:23 AM
  #36  
Current status: After nearly 3000km, the P20E8 came back again. Then around 3 litres AdBlue were addded. Erased the code, seems fine. Then a new code P203D appears, which is Reductant level sensor circuit high. Will some DIYers please help identify the problem? Thanks a lot!
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Dec 1, 2020 | 12:02 PM
  #37  
P203D comes up when the ECM is not getting a reading from the DEF level sender (i.e. if you've got an open circuit), which a corroded electrical connection would do. Did you by any chance overfill the tank? DEF fluid is corrosive and can easily oxidize electrical connectors, which are all on top of the AdBlue tank so overfilling it is always a bad idea. Can you get to the tank, flush the outside (top) with some water and then clean all the electrical connectors with DeoxIT?

As for the P20E8, it's very likely the same issue as before with the module inside the AdBlue tank. Now that ambient temperatures have dropped, materials shrink and/or lose their elasticity so you could have an air leak, or again, it's corroded electrical contacts somewhere along the line.
Reply 0
Dec 1, 2020 | 01:47 PM
  #38  
Thanks, Diabolis, You are right, I did have some overfill 10 months or so before and may not clean thoroughly. I will try DeoxIT and see. Thanks. The P20E8 code seems to disappear after the refill. So if it is air leak, it may be difficult to find out the exact leaking location. Any suggestion to locate it?
Thanks.
Reply 0
Jan 24, 2023 | 11:27 PM
  #39  
hey where can you buy the chip/emulator from i would like to get one
Quote: Hey everyone,

I get the P20B9 check engine light (Reductant Heater A Control Circuit/Open) but the suv seems to run fine. I initially thought the problem was the heater crapping out but I think it's a wiring issue since I don't get the X amount of starts left on my dash. Also, if the heater crapped out, the def would freeze in the -30C temperature we had here in Ontario.

Anyways, so I proceeded to drop the tank and accidentally broke the long/slim black nozzle on the def fluid pump (I was pissed). Do I need the change the entire pump now? Gluing the small piece back in doesn't seem possible. Anyone else with the P20B9 code that could help? A part of me wants to say ?&*( all of this crap and put the chip/emulator in and never touch the crappy SCR system ever again.

VIN = 4JGDA2EB4DA231578

Thank you in advance!
Where can you get the emulator, i would like to buy one
Reply 0
Jan 25, 2023 | 09:38 AM
  #40  
Quote: Where can you get the emulator, i would like to buy one
I know several people that went with Malone for full delete tunes (adblue, egr, swirl flaps and def) and they were very satisfied.

Google "W166 malone tune" and it should pop up.
Reply 0
Jan 6, 2024 | 06:49 PM
  #41  
Quote: Correct. The CEL is gone. Regarding the inspection of the old one, I found nothing out of the ordinary. Everything seemed fine except that it was covered in road junk. I guess that salt and dirt got in the exhaust insert. Can't tell 100% for sure though.
Did you have to relearn after you replaced the line?
I have the same code 20B91B and replaced the line
but the cel comes on when it gets below minus degrees.
any help would be great.
Reply 0
Jan 11, 2024 | 01:47 PM
  #42  
Quote: Did you have to relearn after you replaced the line?
I have the same code 20B91B and replaced the line
but the cel comes on when it gets below minus degrees.
any help would be great.
No adaptations/coding was needed for me. I only erased the CEL and it never came back.
Reply 0
Dec 26, 2024 | 03:35 AM
  #43  
Quote: No adaptations/coding was needed for me. I only erased the CEL and it never came back.
Hey what was the part number? On the gl350 I'm seeing two parts for $300 each.
Reply 0
Dec 26, 2024 | 08:14 AM
  #44  
Quote: Hey what was the part number? On the gl350 I'm seeing two parts for $300 each.
That's a good question! It was 5 years ago, so I unfortunately don't remember the part number. Have you tried calling your local dealership to ask them?

I'm assuming your GL350 is between 2013 and 2015-2016 (X166)? This seems to be the part you need (call your dealer to make sure!):
https://www.idparts.com/diesel-exhau...4-p-15891.html

Here's a video I found on how to do it yourself:

Parts number seems to be 1664702224.

Found one on Ebay for much cheaper!
https://www.ebay.com/p/782852963

Good luck!
Reply 2
Dec 26, 2024 | 12:24 PM
  #45  
Quote: That's a good question! It was 5 years ago, so I unfortunately don't remember the part number. Have you tried calling your local dealership to ask them?

I'm assuming your GL350 is between 2013 and 2015-2016 (X166)? This seems to be the part you need (call your dealer to make sure!):
https://www.idparts.com/diesel-exhau...4-p-15891.html

Here's a video I found on how to do it yourself:
https://www.youtube.com/watch?v=7c69kyJN29U&t=1462s

Parts number seems to be 1664702224.

Found one on Ebay for much cheaper!
https://www.ebay.com/p/782852963

Good luck!
Much appreciated good sir!
Reply 1
Dec 26, 2024 | 03:57 PM
  #46  
Quote: That's a good question! It was 5 years ago, so I unfortunately don't remember the part number. Have you tried calling your local dealership to ask them?

I'm assuming your GL350 is between 2013 and 2015-2016 (X166)? This seems to be the part you need (call your dealer to make sure!):
https://www.idparts.com/diesel-exhau...4-p-15891.html

Here's a video I found on how to do it yourself:
https://www.youtube.com/watch?v=7c69kyJN29U&t=1462s

Parts number seems to be 1664702224.

Found one on Ebay for much cheaper!
https://www.ebay.com/p/782852963

Good luck!
Do you remember how you removed the line off the tank and the SCR? Any tips or tricks you remember? Did the nipple on the dpf tank break upon removal?
Reply 0
Jan 8, 2025 | 08:50 AM
  #47  
Quote: Do you remember how you removed the line off the tank and the SCR? Any tips or tricks you remember? Did the nipple on the dpf tank break upon removal?
It's been so long, I hardly remember. I broke the nipple because I lowered the tank too much/quickly before disconnecting it. So drop it very slowly, try to reach and disonnect the nipple. If you can't reach it, drop it again VERY SLOWLY. Go gradually.

Wish I could help you more.

Good luck! Keep us posted how it went.
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