GLK350 Heater or A/C Failure - Desiccant Bag Warning
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GLK-350
GLK350 Heater or A/C Failure - Desiccant Bag Warning
** The failure of this $25 part, Desiccant Bag, in your heating/cooling system can generate a repair bill of $3,000 or higher. **
Hello, GLK-350 owners.
I am still reeling in this process, with my 2012 GLK-350 only 6 months out of warranty, 7 years old and less than 100K miles.
Our Mercedes GLK-350 went out of warranty on 4/24/2019. This fall, as temperatures in the northeast dropped for the first time since April, we began using heat. We noticed that it was not as hot as it had been in the past. Then it would intermittently blow cool air.
I took the car in for service and diagnosis on 9/26/2019. The initial diagnosis was the thermostat had failed. Estimate of repair $1000. 2 days later, the diagnosis was extended to include a failed heater core. The estimate of repair $2000 additional. I was told that the "desiccant bag" had ruptured, releasing desiccant pellets into the heating/cooling system, wreaking havoc and "gumming" things up.
One day shy of 5 weeks later, the car is still in service as of this post.
I contacted Mercedes corporate in Atlanta, GA. They repeated that they "honored their responsibility" limited to the warranty. Anything further would be up to the dealership.
Meanwhile, my dealership has been mostly absent from the conversation. Only today, after I called, I was informed they were waiting for direction from Mercedes corporate with regard to any relief on the cost. As of today, the total bill for the failure of a $25 part is $3256.00.
Hello, GLK-350 owners.
I am still reeling in this process, with my 2012 GLK-350 only 6 months out of warranty, 7 years old and less than 100K miles.
Our Mercedes GLK-350 went out of warranty on 4/24/2019. This fall, as temperatures in the northeast dropped for the first time since April, we began using heat. We noticed that it was not as hot as it had been in the past. Then it would intermittently blow cool air.
I took the car in for service and diagnosis on 9/26/2019. The initial diagnosis was the thermostat had failed. Estimate of repair $1000. 2 days later, the diagnosis was extended to include a failed heater core. The estimate of repair $2000 additional. I was told that the "desiccant bag" had ruptured, releasing desiccant pellets into the heating/cooling system, wreaking havoc and "gumming" things up.
One day shy of 5 weeks later, the car is still in service as of this post.
I contacted Mercedes corporate in Atlanta, GA. They repeated that they "honored their responsibility" limited to the warranty. Anything further would be up to the dealership.
Meanwhile, my dealership has been mostly absent from the conversation. Only today, after I called, I was informed they were waiting for direction from Mercedes corporate with regard to any relief on the cost. As of today, the total bill for the failure of a $25 part is $3256.00.
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2013 glk 350
I just read the average cost to replace a thermostat is 359-420, and your charged 120$ for a 30$ thermostat, even that price is a screw job. At 1000$, I think you need to question everything. The thermostat is a simple job your billed 2 hours for. 1000 is crooked.
And The whole story of what failed sounds suspicious. If your heat was intermittent a malfunctioning vent door or heat valve makes sense, A clogged heater core won’t change and give heat one day and none the next, and I really think bs because the heater core is a sealed system with the motors cooling system. There WONT be a decisant bag inside the cooling system. Doesn’t a decisant bag operate by removing moisture from the Air? It honestly all sounds like a big rip off. if something clogged the outside coils of the heater core it could have been blown or washed off.
And The whole story of what failed sounds suspicious. If your heat was intermittent a malfunctioning vent door or heat valve makes sense, A clogged heater core won’t change and give heat one day and none the next, and I really think bs because the heater core is a sealed system with the motors cooling system. There WONT be a decisant bag inside the cooling system. Doesn’t a decisant bag operate by removing moisture from the Air? It honestly all sounds like a big rip off. if something clogged the outside coils of the heater core it could have been blown or washed off.
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GLK-350
I completely agree, Mmr1. I think there's a lot of BS in this story. I pressured the dealer to explain to me how the desiccant bag would be involved in the cooling system and they insisted that it was. They are sticking with the story that the desiccant pellets contaminated the coolant and caused failure of the thermostat and the heater core. I need to find a mechanic who is thoroughly familiar with the design of this particular system.
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GLK-350
Hello, chassis. Yes, I went to an experienced auto shop that I've worked with in the past and they even refused to give me an estimate! The said, from experience, they knew that this system was extremely labor-intensive to diagnose and repair. They would only give me a quote on parts, but not labor which would have to be an open-ended deal. So, they declined!
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2013 glk 350
Are you familiar with what a decisant bag is? It’s a dry porous bag with something like silica that absorbs moisture . It’s often found in medicines and electronics and any product to remove excess moisture. I don’t believe a product like that would be useful in a vehicle , because after it’s absorbed all the moisture it can absorb, ( which might only take a few days) to remove the moisture and make it work again you have to cook out the moisture at over 200f or you can microwave the decisant. I use them for my cameras , I have 6, 2” blocks of this that I need to cook out the moisture every month. I’m sure no vehicle has the means to (Cook) the decisant. I think your being fed an expensive line of bull ****.
As far as the thermostat , they can just look at the temperature gauge and drive it from cold to see if you actually needed a new one. For example my 350 goes to full temp in 12 minutes at 32f.
Also if it actually ruined the thermostat and heater core, what about the radiator and all the small cooling passages in the motor? And inside the cooling system, having a Decisant bag would be ridiculous, this is just my uneducated opinion.
As far as the thermostat , they can just look at the temperature gauge and drive it from cold to see if you actually needed a new one. For example my 350 goes to full temp in 12 minutes at 32f.
Also if it actually ruined the thermostat and heater core, what about the radiator and all the small cooling passages in the motor? And inside the cooling system, having a Decisant bag would be ridiculous, this is just my uneducated opinion.
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You are right, Mmr1. All of it really doesn't add up.
No. There was no fluctuation in the engine temperature gauge. I made it a point to monitor that when the heater first started to fluctuate.
I still do not understand the involvement of a desiccant bag in a cooling system loop, but it is a listed part.
No. There was no fluctuation in the engine temperature gauge. I made it a point to monitor that when the heater first started to fluctuate.
I still do not understand the involvement of a desiccant bag in a cooling system loop, but it is a listed part.
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2017 GLE350 4MATIC
It's plausible, although with unknown likelihood, that the desiccant bag could rupture. The system in question is the air side of a water-to-air heat exchange system. Not related to radiator or engine coolant flow paths.
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2012 GLK
