GLB ISSUES
Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
GLB ISSUES
Hi,
having just joined with a 2020 GLB 220d I have had for 18 months.
the car is great and I love everything about it except the niggling issues I have with it:
1) DPF problem after 20k miles - solution manual regen and light goes out.
2) engine light comes back on again and goes off - no fault found.
3) cooling fan comes on at night when car is locked and flattens the battery if you don’t catch it in time - solution unlock the car and it stops. Dealer solution - change the front under bumper wiring harness as faulty. Car lasted 24 hours and caught the fan on again!
car is now in dealer for third time and the amber light came on again while I was waiting for them to pick it up!
2 calls to roadside recovery as well when the battery went flat at home and I didn’t catch it.
anyone else had issues like this? I love it but I’m thinking of dropping it.
having just joined with a 2020 GLB 220d I have had for 18 months.
the car is great and I love everything about it except the niggling issues I have with it:
1) DPF problem after 20k miles - solution manual regen and light goes out.
2) engine light comes back on again and goes off - no fault found.
3) cooling fan comes on at night when car is locked and flattens the battery if you don’t catch it in time - solution unlock the car and it stops. Dealer solution - change the front under bumper wiring harness as faulty. Car lasted 24 hours and caught the fan on again!
car is now in dealer for third time and the amber light came on again while I was waiting for them to pick it up!
2 calls to roadside recovery as well when the battery went flat at home and I didn’t catch it.
anyone else had issues like this? I love it but I’m thinking of dropping it.
MBWorld God!
Joined: Dec 2019
Posts: 32,536
Likes: 6,358
Hi,
having just joined with a 2020 GLB 220d I have had for 18 months.
the car is great and I love everything about it except the niggling issues I have with it:
1) DPF problem after 20k miles - solution manual regen and light goes out.
2) engine light comes back on again and goes off - no fault found.
3) cooling fan comes on at night when car is locked and flattens the battery if you don’t catch it in time - solution unlock the car and it stops. Dealer solution - change the front under bumper wiring harness as faulty. Car lasted 24 hours and caught the fan on again!
car is now in dealer for third time and the amber light came on again while I was waiting for them to pick it up!
2 calls to roadside recovery as well when the battery went flat at home and I didn’t catch it.
anyone else had issues like this? I love it but I’m thinking of dropping it.
having just joined with a 2020 GLB 220d I have had for 18 months.
the car is great and I love everything about it except the niggling issues I have with it:
1) DPF problem after 20k miles - solution manual regen and light goes out.
2) engine light comes back on again and goes off - no fault found.
3) cooling fan comes on at night when car is locked and flattens the battery if you don’t catch it in time - solution unlock the car and it stops. Dealer solution - change the front under bumper wiring harness as faulty. Car lasted 24 hours and caught the fan on again!
car is now in dealer for third time and the amber light came on again while I was waiting for them to pick it up!
2 calls to roadside recovery as well when the battery went flat at home and I didn’t catch it.
anyone else had issues like this? I love it but I’m thinking of dropping it.
Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
Hi, thanks for the info.
I haven’t got a scanner - that’s next after just purchasing a NOCO booster jump start and battery charger - not used a charger since the 80’s!
been down the gas cap route, remembering when I filled up and coincidence - filled up on Saturday and no problems but the light came on this morning. I tried the cap and it only fits one way round and clicks once because of the cap/cover restraint. However there could be a faulty cap seal? Might source one and change it.
I will push the dealer on the code as the last time they didn’t mention it.
I remain convinced the fan issue may be linked to the Canbus wake and the central locking as the fault occurs only when locked and asleep and stops when you unlock the car? Ie the car wakes and thinks fan shouldn’t be on and switches it off.
if my regular dealer can’t sort it I might take it to a local auto electrics expert but make him aware of all the trouble in case he doesn’t want to get involved and I don’t want major expense if he can’t find the fault while the car is still under warranty. Could try another dealer but will they be any different - sort of losing the confidence here.
I haven’t got a scanner - that’s next after just purchasing a NOCO booster jump start and battery charger - not used a charger since the 80’s!
been down the gas cap route, remembering when I filled up and coincidence - filled up on Saturday and no problems but the light came on this morning. I tried the cap and it only fits one way round and clicks once because of the cap/cover restraint. However there could be a faulty cap seal? Might source one and change it.
I will push the dealer on the code as the last time they didn’t mention it.
I remain convinced the fan issue may be linked to the Canbus wake and the central locking as the fault occurs only when locked and asleep and stops when you unlock the car? Ie the car wakes and thinks fan shouldn’t be on and switches it off.
if my regular dealer can’t sort it I might take it to a local auto electrics expert but make him aware of all the trouble in case he doesn’t want to get involved and I don’t want major expense if he can’t find the fault while the car is still under warranty. Could try another dealer but will they be any different - sort of losing the confidence here.
MBWorld God!
Joined: Dec 2019
Posts: 32,536
Likes: 6,358
Hi, thanks for the info.
I haven’t got a scanner - that’s next after just purchasing a NOCO booster jump start and battery charger - not used a charger since the 80’s!
been down the gas cap route, remembering when I filled up and coincidence - filled up on Saturday and no problems but the light came on this morning. I tried the cap and it only fits one way round and clicks once because of the cap/cover restraint. However there could be a faulty cap seal? Might source one and change it.
I will push the dealer on the code as the last time they didn’t mention it.
I remain convinced the fan issue may be linked to the Canbus wake and the central locking as the fault occurs only when locked and asleep and stops when you unlock the car? Ie the car wakes and thinks fan shouldn’t be on and switches it off.
if my regular dealer can’t sort it I might take it to a local auto electrics expert but make him aware of all the trouble in case he doesn’t want to get involved and I don’t want major expense if he can’t find the fault while the car is still under warranty. Could try another dealer but will they be any different - sort of losing the confidence here.
I haven’t got a scanner - that’s next after just purchasing a NOCO booster jump start and battery charger - not used a charger since the 80’s!
been down the gas cap route, remembering when I filled up and coincidence - filled up on Saturday and no problems but the light came on this morning. I tried the cap and it only fits one way round and clicks once because of the cap/cover restraint. However there could be a faulty cap seal? Might source one and change it.
I will push the dealer on the code as the last time they didn’t mention it.
I remain convinced the fan issue may be linked to the Canbus wake and the central locking as the fault occurs only when locked and asleep and stops when you unlock the car? Ie the car wakes and thinks fan shouldn’t be on and switches it off.
if my regular dealer can’t sort it I might take it to a local auto electrics expert but make him aware of all the trouble in case he doesn’t want to get involved and I don’t want major expense if he can’t find the fault while the car is still under warranty. Could try another dealer but will they be any different - sort of losing the confidence here.
I would try a different dealership if the first one isn't giving you satisfying results.
As for the fan kicking in, something in the vehicle might be overheating or a sensor is defective reporting high temperatures triggering the fan, maybe just maybe when you open the door the car thinks you will go for a drive and therefore will cool down the car so it decided to shut off the fan.
The check engine light maybe but not fully confident be cause by a faulty thermostat or a related sensor.
While you go and look for a different dealership, get a generic scanner and see if you find any codes, if the code isn't hidden that only an MB system can scan a generic scanner will be able to pick it up. Good luck!
Super Member
Joined: Jan 2021
Posts: 557
Likes: 204
2021 Mercedes GLB250 4Matic
Sounds like you have first model year Gremlins in your car. It's sounds very frustrating.
I would agree with W205C43PFL, that logically it could be a faulty sensor or programming issue. Did your dealer try to update software in your car?
I would agree with W205C43PFL, that logically it could be a faulty sensor or programming issue. Did your dealer try to update software in your car?
Last edited by Vladimir Livson; Feb 13, 2023 at 03:03 PM.
Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
Yes, software update done at dealer and by roadside rescue. I asked them to check the temp sensor but they found this faulty wiring harness and pinned all their hopes on that.
at least they seem to be working on the car now. Checking on the signals I keep getting from the app they have been on it since lunchtime to about 6pm but no updates given.
I suppose given first year car they may be on the learning curve with faults appearing but I don’t want this still outstanding when the warranty runs out.
I said to the dealer I suppose this will be reflected in the trade in price if I want rid - the reply was not at all because we will just fix it for the next owner!!
I replied why don’t you just fix it for me?
at least they seem to be working on the car now. Checking on the signals I keep getting from the app they have been on it since lunchtime to about 6pm but no updates given.
I suppose given first year car they may be on the learning curve with faults appearing but I don’t want this still outstanding when the warranty runs out.
I said to the dealer I suppose this will be reflected in the trade in price if I want rid - the reply was not at all because we will just fix it for the next owner!!
I replied why don’t you just fix it for me?
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MBWorld Fanatic!
Joined: Sep 2013
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
GLB220d and your profile says GB — so a lot of us will not be immediately familiar with the exact model, but the cooling fan control circuit should be very similar.
If the fan is running, then something is telling the fan to run. It’s not just a thermostat connected to the fan. A sensor has to send a signal to the ECU, then the ECU needs to send a signal to the controller, which then actuates a relay or SCR to send voltage to the fan. I’m definitely not an expert on the GLB, but I think they need to look at live data while the fan is running when it should not to see where this error is occurring because your observation seems logical to me. The problem could be physical or it could be in the software. But I noticed that when I scanned mine for a check engine light that the control system is much more complicated than my 2013.
This is mostly a SWAG but —
I think the problem is somewhere between the ECU and the controller. I see a situation where a single dropped bit in the programming could do this, but you say that the ECU has been flashed twice. I wonder if it needs to be erased and re-initialized. Update may not catch the problem because when the system asks the car “Are you OK” if the car answers “Yes” it may not refresh anything that’s not flagged.
Does your country have a problem resolution center? The US has one that can help dealers sort out really difficult problems.
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Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
Thanks for the info,
it all makes sense and the car works perfectly when I am using it. Obviously in the summer hotter months you can get overrun of the fan when the car is stopped. But I did notice a couple of times I had done a short journey where the car didn’t get warm and the fan came on when I switched it off. I just can’t remember if the overrun stopped when I locked the car as it does when I unlock it if I catch it doing it 24hrs later? This is why I came up with it being linked to the central locking - so your theory of live data could show normal running when the car is being used? Perhaps it might show something else. But I’ve noticed the car is in the workshop with everything unlocked and window and bonnet open so if my theory is right it won’t show? They would have to lock it and data record the fan operation for a couple of days to flag it and even then it might not?
im only assuming this because it only seems to happen in this sleep/wake mode.
as far as I know there is only Mercedes Customer service (based in Holland) for this sort of issue in UK. They know about it but are very slow in response.
it all makes sense and the car works perfectly when I am using it. Obviously in the summer hotter months you can get overrun of the fan when the car is stopped. But I did notice a couple of times I had done a short journey where the car didn’t get warm and the fan came on when I switched it off. I just can’t remember if the overrun stopped when I locked the car as it does when I unlock it if I catch it doing it 24hrs later? This is why I came up with it being linked to the central locking - so your theory of live data could show normal running when the car is being used? Perhaps it might show something else. But I’ve noticed the car is in the workshop with everything unlocked and window and bonnet open so if my theory is right it won’t show? They would have to lock it and data record the fan operation for a couple of days to flag it and even then it might not?
im only assuming this because it only seems to happen in this sleep/wake mode.
as far as I know there is only Mercedes Customer service (based in Holland) for this sort of issue in UK. They know about it but are very slow in response.
MBWorld God!
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Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
Hi all,
an update on the cooling fan fault:
car went back in to the dealer 3 weeks ago as the fan was running and notified to me by a man walking his dog! (Why is it always dog walkers who discover everything?)
they had the car for a week and finally identified the cooling fan as the culprit. Had the car back and all is good for 3 weeks - battery staying charged and stop/start function working more than it ever has.
this morning though engine light was back on for a couple of hours - out now.
so I am thinking what have I done the same as before? One long journey after fill up and then next couple of days couple of short journeys. This same circumstances have occurred before and light on/off. So I thought let’s change the fuel cap - might be faulty? It only clicks once so would be very difficult to leave loose so it maybe seal?
anyway it’s cheaper than driving to the dealer and getting taxi home when there is no cars to lend? At least I can say I’ve changed that when they suggest is your fuel cap loose. Just trying to buy one now.
an update on the cooling fan fault:
car went back in to the dealer 3 weeks ago as the fan was running and notified to me by a man walking his dog! (Why is it always dog walkers who discover everything?)
they had the car for a week and finally identified the cooling fan as the culprit. Had the car back and all is good for 3 weeks - battery staying charged and stop/start function working more than it ever has.
this morning though engine light was back on for a couple of hours - out now.
so I am thinking what have I done the same as before? One long journey after fill up and then next couple of days couple of short journeys. This same circumstances have occurred before and light on/off. So I thought let’s change the fuel cap - might be faulty? It only clicks once so would be very difficult to leave loose so it maybe seal?
anyway it’s cheaper than driving to the dealer and getting taxi home when there is no cars to lend? At least I can say I’ve changed that when they suggest is your fuel cap loose. Just trying to buy one now.
Last edited by Neilgw; Mar 11, 2023 at 04:00 AM. Reason: Further update
Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
Hi Folks,
spoke too soon!
cooling fan back on in the early hours - battery nearly flat - same fault - amber EML again now not going out.
called breakdown as garage couldn’t look at it til 27th March!
The reported a bunch of communication faults - technician said - convinced it’s water ingress you need to take it in and they will get you a car to use.
took it in myself, had a taxi home, hire car supplied at 7pm.
according to the app an hour later everything unlocked and they were looking at it!
raised another case with customer services and asked the dealer bearing all this in mind what sort of deal they could do? All Mercs can’t be the same - can they?
spoke too soon!
cooling fan back on in the early hours - battery nearly flat - same fault - amber EML again now not going out.
called breakdown as garage couldn’t look at it til 27th March!
The reported a bunch of communication faults - technician said - convinced it’s water ingress you need to take it in and they will get you a car to use.
took it in myself, had a taxi home, hire car supplied at 7pm.
according to the app an hour later everything unlocked and they were looking at it!
raised another case with customer services and asked the dealer bearing all this in mind what sort of deal they could do? All Mercs can’t be the same - can they?
MBWorld Fanatic!
Joined: Sep 2013
Posts: 2,349
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
No, they aren’t all the same. We’ve been driving them for decades. 186k, 185k, 155k miles, retired. 104k, 41k miles still going OK. Things do break, but we have never had one that they couldn’t fix. The 4 cylinder engines have had problems that the 6 cylinder ones never had, but they diagnosed and repaired the problem on the first try.
Thread Starter
Newbie
Joined: Feb 2023
Posts: 9
Likes: 3
From: Warwickshire, UK
Glb220d
Hi,
Update on issues:
After fitting the second cooling pump and loom due to corrosion after 1 month then adding silicon sealant around the joint the car is ok again. I hope they used neutral cure silicon because if they don’t the corrosion will rush in quicker than if it was stood in water 24/7.
anyway decided to upgrade to a 2022 GLB in a premium plus trim with the sunroof. Had to go long distance delivery as the best trade in and the colour I wanted.
came today and looks great. Only thing is a lot of options are missing even though it is a top of the range. No power tailgate, no electric memory seats, no wireless phone charger pad, one front sport seat with knee extension instead of two, no puddle illuminations on the door mirrors,
I think it’s due to the chip shortage they had back then. So an expensive upgrade for a sunroof and lumbar support! Had to drop the other one though and this was the best compromise so I’m going to enjoy it
Update on issues:
After fitting the second cooling pump and loom due to corrosion after 1 month then adding silicon sealant around the joint the car is ok again. I hope they used neutral cure silicon because if they don’t the corrosion will rush in quicker than if it was stood in water 24/7.
anyway decided to upgrade to a 2022 GLB in a premium plus trim with the sunroof. Had to go long distance delivery as the best trade in and the colour I wanted.
came today and looks great. Only thing is a lot of options are missing even though it is a top of the range. No power tailgate, no electric memory seats, no wireless phone charger pad, one front sport seat with knee extension instead of two, no puddle illuminations on the door mirrors,
I think it’s due to the chip shortage they had back then. So an expensive upgrade for a sunroof and lumbar support! Had to drop the other one though and this was the best compromise so I’m going to enjoy it
MBWorld God!
Joined: Dec 2019
Posts: 32,536
Likes: 6,358
Hi,
Update on issues:
After fitting the second cooling pump and loom due to corrosion after 1 month then adding silicon sealant around the joint the car is ok again. I hope they used neutral cure silicon because if they don’t the corrosion will rush in quicker than if it was stood in water 24/7.
anyway decided to upgrade to a 2022 GLB in a premium plus trim with the sunroof. Had to go long distance delivery as the best trade in and the colour I wanted.
came today and looks great. Only thing is a lot of options are missing even though it is a top of the range. No power tailgate, no electric memory seats, no wireless phone charger pad, one front sport seat with knee extension instead of two, no puddle illuminations on the door mirrors,
I think it’s due to the chip shortage they had back then. So an expensive upgrade for a sunroof and lumbar support! Had to drop the other one though and this was the best compromise so I’m going to enjoy it
Update on issues:
After fitting the second cooling pump and loom due to corrosion after 1 month then adding silicon sealant around the joint the car is ok again. I hope they used neutral cure silicon because if they don’t the corrosion will rush in quicker than if it was stood in water 24/7.
anyway decided to upgrade to a 2022 GLB in a premium plus trim with the sunroof. Had to go long distance delivery as the best trade in and the colour I wanted.
came today and looks great. Only thing is a lot of options are missing even though it is a top of the range. No power tailgate, no electric memory seats, no wireless phone charger pad, one front sport seat with knee extension instead of two, no puddle illuminations on the door mirrors,
I think it’s due to the chip shortage they had back then. So an expensive upgrade for a sunroof and lumbar support! Had to drop the other one though and this was the best compromise so I’m going to enjoy it
Newbie
Joined: Oct 2024
Posts: 1
Likes: 0
Sensor problems
Hi,
having just joined with a 2020 GLB 220d I have had for 18 months.
the car is great and I love everything about it except the niggling issues I have with it:
1) DPF problem after 20k miles - solution manual regen and light goes out.
2) engine light comes back on again and goes off - no fault found.
3) cooling fan comes on at night when car is locked and flattens the battery if you don’t catch it in time - solution unlock the car and it stops. Dealer solution - change the front under bumper wiring harness as faulty. Car lasted 24 hours and caught the fan on again!
car is now in dealer for third time and the amber light came on again while I was waiting for them to pick it up!
2 calls to roadside recovery as well when the battery went flat at home and I didn’t catch it.
anyone else had issues like this? I love it but I’m thinking of dropping it.
having just joined with a 2020 GLB 220d I have had for 18 months.
the car is great and I love everything about it except the niggling issues I have with it:
1) DPF problem after 20k miles - solution manual regen and light goes out.
2) engine light comes back on again and goes off - no fault found.
3) cooling fan comes on at night when car is locked and flattens the battery if you don’t catch it in time - solution unlock the car and it stops. Dealer solution - change the front under bumper wiring harness as faulty. Car lasted 24 hours and caught the fan on again!
car is now in dealer for third time and the amber light came on again while I was waiting for them to pick it up!
2 calls to roadside recovery as well when the battery went flat at home and I didn’t catch it.
anyone else had issues like this? I love it but I’m thinking of dropping it.
weve had the same problem it’s all down to merc using inferior sensors during the covid lockdown it’s a dpf sensor that needs replacing. We also have a transmission whine at 30mph any one have this
