TSB for clogged heater core / code P2457

inthewoods

Veteran Member
Joined
Mar 24, 2014
Location
Carson, WA
TDI
2014 Passat SE Manual
Okay,

For all who are going through the clogged heater core issues take a look at the link for the Technical Service Bulletin regarding this issue:

https://drive.google.com/file/d/0ByxgazxO4YLZV0hyTm1OVm1tNE0/view

Hopefully this will shed some light on the issue, and it looks like a simple PH test can be preformed to identify future issues. Also from what the Service Tech said the new heater core has be redesigned to allow for better flow reducing the chance of plugging.
 
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jrm

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Jul 24, 2013
Location
Oregon
TDI
2013 Passat SE with nav (totaled)
first step in being covered by a extended warranty :D
 

unixb0y

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Oct 1, 2003
Location
Manitoba, Canada
TDI
2013 Passat Comfortline 6MT Nav
Okay,

For all who are going through the clogged heater core issues take a look at the link for the Technical Service Bulletin regarding this issue:

https://drive.google.com/file/d/0ByxgazxO4YLZd2dEdUpwenhkcjQ/view

Hopefully this will shed some light on the issue, and it looks like a simple PH test can be preformed to identify future issues. Also from what the Service Tech said the new heater core has be redesigned to allow for better flow reducing the chance of plugging.
Interesting that the TSB was released on July 17, 2015.

How low can 50/50 ratio go? In canada there was a tsb to flush coolant and replace with -45 mixed coolant for 2013-2014 models.
 

tdiatlast

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Joined
Jan 21, 2009
Location
Fort Worth, Texas
TDI
2009 Sportwagen (boughtback); 2014 Passat TDI SEL (boughtback)
Is the "flux" contaminant gone after this flush/fill, or will it continue to leach into the coolant and be an issue?
 

1998redwagon

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Joined
Jul 19, 2011
Location
warba, minnesota
TDI
2013 passat 6M tungsten/cornsilk
Yes I too wonder if this is a fix or if it is a temporary fix. Clearly owners will have to be on top of changing the coolant if they want to maintain flow through the heater in the future. Either that or the new heater core is made differently.
 

MB2VW

Veteran Member
Joined
Jun 8, 2000
Location
Lighthouse Pt., FL USA
TDI
2015 Passat SEL,
Having an out of warranty 2012 NMS, I'm curious why the 2012 isn't cited in the TSB.

Living in S. Florida, The heater isn't used much. I checked it yesterday and the passenger side is putting out as much heat as the driver's side.

Based on this forums numerous heater core posts of folks having clogged cores, I recon it wouldn't be a bad idea for a flush and refill of the cooling system.

The VW Maintenance schedule only calls for checking coolant every 40k, but does not mention replacement/flush.

I think i have some pH strips laying around somewhere. I'll try testing fresh vs used coolant to see if I can ascertain those numbers. If I'm successful I will post them.

Is there a good reference on how to perform a flush on this model, somewhere out there?
 

MyAvocation

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Joined
Jun 9, 2004
Location
Hoffman Estates, IL
TDI
2017 Passat SEL TSI
Living in S. Florida, The heater isn't used much. I checked it yesterday and the passenger side is putting out as much heat as the driver's side.
Just guessing, yet again, but wouldn't a stagnant core be more susceptible?
 

tdiatlast

Top Post Dawg
Joined
Jan 21, 2009
Location
Fort Worth, Texas
TDI
2009 Sportwagen (boughtback); 2014 Passat TDI SEL (boughtback)
HVAC system doesn't regulate flow of coolant through the heater core, it regulates the air flowing through it. AFAIK, coolant flow is a constant.
 

kydsid

Veteran Member
Joined
Apr 18, 2012
Location
Texas
TDI
2012 Passat
Having an out of warranty 2012 NMS, I'm curious why the 2012 isn't cited in the TSB.
There was an AC change from 2012 to 2013 iirc. My 12 SE has auto temp AC. That was changed and some physical changes. The AC air inlet is different and 13s i believe is when they brought rear AC vents. Perhaps a different heat core also accompanied these changes.
 

VeeDubTDI

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Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Having an out of warranty 2012 NMS, I'm curious why the 2012 isn't cited in the TSB.

Living in S. Florida, The heater isn't used much. I checked it yesterday and the passenger side is putting out as much heat as the driver's side.

Based on this forums numerous heater core posts of folks having clogged cores, I recon it wouldn't be a bad idea for a flush and refill of the cooling system.

The VW Maintenance schedule only calls for checking coolant every 40k, but does not mention replacement/flush.

I think i have some pH strips laying around somewhere. I'll try testing fresh vs used coolant to see if I can ascertain those numbers. If I'm successful I will post them.

Is there a good reference on how to perform a flush on this model, somewhere out there?
Perhaps there was a change in manufacturing or design of the radiator or another part of the cooling system between 2012 and 2013 that resulted in the excess flux.
 

CTValleyTDI

Member
Joined
Sep 21, 2015
Location
MA and VT
TDI
2014 Passat TDI SE
After writing a letter to VW of America, they agreed to pay for our heater core replacement for a 24 month-old NMS Passat TDI (just out of warranty). My hand was strengthened by details learned about the cooling system issues on this site.
The loaner car is a new 2015 TDI--which of course can't be sold right now. I wonder how many dealers are putting their stuck TDI inventory to 'creative use'?
 

jrm

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Jul 24, 2013
Location
Oregon
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2013 Passat SE with nav (totaled)
my dealer has all the tdi's in the overflow lot 2 miles away from the dealer. All covered in dust and grime, weeds growing up past the bumpers. I would pick another one up it were in the low $20K range and 0%
 

oldpoopie

Vendor
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May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
Are there any concerns about radiator clogging as collateral damage?
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
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Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Are there any concerns about radiator clogging as collateral damage?
I'd be more concerned with the oil cooler than the radiator. I suppose it's possible for everything to clog, but it would start with the coolers that have the smallest internal passages, as they act like filters in the system for the crud to get caught in.
 

kydsid

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Apr 18, 2012
Location
Texas
TDI
2012 Passat
Anyone know what "proper" ph level actually means?
Id like to know also. As an educates guess the MSDS for various G13 coolants says 8.1 to 8.6. Distilled water can be from 6-7 in pH. So a 50/50 mix could end up anywhere in the spectrum but neutral is the best imo.
 

banshee365

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Nov 4, 2012
Location
FL
TDI
06 Jetta
So the TSB say's to just flush the system with a fresh 50/50 mix? No de-scaling chemical or anything like that?
 

MB2VW

Veteran Member
Joined
Jun 8, 2000
Location
Lighthouse Pt., FL USA
TDI
2015 Passat SEL,
Finally had some time to poke at the pH question. I found some old litmus paper in my tool cabinet. The two products I have on hand are one roll of paper good for pH 3.0 to 5.5, and the second for pH 9.0 to 13.0.

I dipped fresh VW coolant with a 50/50 mix and the best I could recon is 9.5 pH. I measured my S. Florida tap water, and it too measured 9.5.

I pulled some coolant from my Passat, and it too measured 9.0 to 9.5 ( in between color).

Based on wikipedia : "Solutions with a pH less than 7 are acidic and solutions with a pH greater than 7 are alkaline or basic. Pure water is neutral, being neither an acid nor a base."

I suppose I'm doing ok.

For what it's worth I guess...
 
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tdiatlast

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FWIW: I wonder if your "old litmus paper in my tool cabinet" is too old to be of any value? ...just a thought...
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
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Springfield, VA
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‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
FWIW: I wonder if your "old litmus paper in my tool cabinet" is too old to be of any value? ...just a thought...
Jason just bought some fresh litmus paper, so we'll see what it says.
 

MB2VW

Veteran Member
Joined
Jun 8, 2000
Location
Lighthouse Pt., FL USA
TDI
2015 Passat SEL,
FWIW: I wonder if your "old litmus paper in my tool cabinet" is too old to be of any value? ...just a thought...
I wondered that too. It was wrapped in tin foil and seems to behave predictably, but I would advise that my post's data collections were unscientific by nature & no animals were harmed in it's production.
 

tdiatlast

Top Post Dawg
Joined
Jan 21, 2009
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Fort Worth, Texas
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MB2VW: Maybe it's best to delete your post? You won't harm any animal doing that, either! :D
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
I'd leave it. Let's compare the results to my new strips... hopefully I'll remember to get to it tonight.

-J
 

czeetah

Veteran Member
Joined
Jun 29, 2014
Location
Mountains, NC
TDI
2014 Passat 6MT / Opera Red
Well if the problem is too much flux ... Rather than splicing a flux capacitor into the cooling system we could splice in a flux resistor.
 

dogger37

Veteran Member
Joined
May 28, 2012
Location
PA
TDI
2012 passat
New update.....

Car is at dealer now with its second clogged heater core. They are replacing it and cleaning the system with a chemical multiple times according to the service manager. I will try and find out what they are using and report back.
 

BKmetz

Administrator, Member #10
Staff member
Joined
Sep 25, 1997
Location
Illinois
TDI
2015 Passat, titanium beige, 6MT
I took my car in Friday and had the heater core replaced per the TSB. Not fun when you have no warranty. I'll contact VW Monday and see if I can get some kind of reimbursement. I know about the gift card and applied for one but I won't see that for several weeks according to VW.

This is a known defect and should not matter on which engine the car has. Are there any reports on the gasser Passats having heater core issues? Wife's Passat has the same amount of heat out of her car's vents. Her car also has much lower mileage than mine, hers ~15k Vs mine ~56k.

:confused:
 
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