TSB180139-111120

11/21/2019
UL2 DEF Dosing Unit External DEF Leaks
Technical Service Bulletin
Technical Service Bulletin: TSB180139
UL2 DEF Dosing Unit External DEF Leaks
Released Date: 11-Nov-2019
UL2 DEF Dosing Unit External DEF Leaks
Warranty Statement
The information in this document has no effect on present warranty coverage or repair practices,
nor does it authorize TRP or Campaign actions.
Contents
Product Affected
B6.7 CM2350 B121B
L9 CM2350 L116B
QSG12 CM2350 G110
QSK19 CM2350 K105
QSK50 CM2350 K108
QSK60 CM2350 K116
QSK60 CM2350 K117
QSK60 CM2350 K121
QSK95 CM2350 K113
X12 CM2350 X119B
X15 CM2350 X114B
X15 CM2350 X116B
Issue
External aftertreatment diesel exhaust fluid leaks at aftertreatment diesel exhaust fluid pump filter
housing.
Symptom:
External aftertreatment diesel exhaust fluid leak is present at aftertreatment diesel exhaust
fluid dosing unit filter housing vent.
External aftertreatment diesel exhaust fluid leak is present between the aluminum dosing unit
housing and diesel exhaust fluid dosing unit filter housing.
Root Cause:
A hard interference between the diesel exhaust fluid dosing unit filter, freeze membrane, and
filter housing can cause the freeze membrane to tear and allow aftertreatment diesel exhaust
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UL2 DEF Dosing Unit External DEF Leaks
fluid to leak into the filter housing and leak out the filter housing vent.
Some diesel exhaust fluid dosing unit filter housings have been observed to swell over time
and lose clamping force required to seal DEF between the dosing unit housing and the freeze
membrane.
Verification
Perform diesel exhaust fluid leak test. Refer to Procedure 011-080
(/qs3/pubsys2/xml/en/procedures/493/493-011-080.html) in Section 11. Observe for leakage
between the plastic filter cap and aluminum dosing unit housing. See Figures 1 and 2 below.
Figure 1, Leak between Aftertreatment Diesel Exhaust Fluid Dosing Unit and Filter Housing.
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UL2 DEF Dosing Unit External DEF Leaks
Figure 2, Signs of External DEF Leak Present on Aftertreatment Diesel Exhaust Fluid Dosing
Unit.
Visually inspect diesel exhaust fluid dosing unit filter housing for signs of leakage from filter
housing vent. See Figures 3 and 4 below.
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UL2 DEF Dosing Unit External DEF Leaks
Figure 3, Aftertreatment Diesel Exhaust Fluid Dosing Unit with External Leak
Figure 4, Damaged Aftertreatment Diesel Exhaust Fluid Dosing Unit Freeze Membrane
Resolution
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UL2 DEF Dosing Unit External DEF Leaks
A new aftertreatment diesel exhaust fluid dosing unit filter design has been released to prevent
interference between aftertreatment diesel exhaust fluid dosing unit filter, freeze membrane, and
filter housing. This improvement is a running change and no new part number will be released.
Service Instructions
If leakage is present, remove aftertreatment diesel exhaust fluid dosing unit filter housing and
freeze membrane and inspect for damage.
If an external leak is present at aftertreatment diesel exhaust fluid dosing unit filter housing,
replace the diesel exhaust fluid dosing unit filter, freeze membrane, and filter housing. See
corresponding service manual. Refer to Procedure 011-060
(/qs3/pubsys2/xml/en/procedures/493/493-011-060.html) in Section 11.
All required parts are contained in diesel exhaust fluid dosing unit filter kit, Part Number
4388378.
Production Status
Implemented for production. See Table 1.
Table 1, Production Information
Diesel Exhaust
Fluid Dosing Unit
Serial Number First1
Build Date
Production Line
Number
Plant
RF202423_5
June 20th, 2018
Line 2
CES Juarez
RF203686_6
June 20th, 2018
Line 3
CES Juarez
1DEF
dosing unit serial number can be found on diesel exhaust fluid pump.
Document History
Date
Details
2018-10-15
Module Created
2019-11-7
Non-Product Problem Solving (PPS)
Last Modified: 11-Nov-2019
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