TSB220251

1/5/23, 1:23 PM
Bosch® Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Unit Replacement for Fault Code 3559 Active/Inactive
Technical Service Bulletin
Technical Service Bulletin: TSB220251
Released Date: 07-Dec-2022
Bosch® Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Unit Replacement for Fault
Code 3559 Active/Inactive
Bosch® Aftertreatment Diesel Exhaust Fluid (DEF)
Dosing Unit Replacement for Fault Code 3559
Active/Inactive
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.
Information Only - OEM Related Matter Not Covered By Cummins® - Contact Appropriate OEM
Dealer or OEM Representative For Additional Information
Contents
Product Affected
L9 CM2350 L123B (Gillig™)
L9 CM2350 L123B (NOVABUS)
L9 CM2350 L123B (New Flyer™)
Issue
Symptom:
Fault Code 3559
Root Cause:
OEM wiring connector to the aftertreatment DEF dosing unit is loose at the back of the
connector at the weather pack seal (see Figures).
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Bosch® Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Unit Replacement for Fault Code 3559 Active/Inactive
Figure 1, Loose Wire at Back of OEM Wiring Connector to Aftertreatment DEF Dosing Unit.
Figure 2, Loose Wire at Back of OEM Wiring Connector to Aftertreatment DEF Dosing Unit.
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Bosch® Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Unit Replacement for Fault Code 3559 Active/Inactive
Figure 3, Loose Wire at Back of OEM Wiring Connector to Aftertreatment DEF Dosing Unit.
Verification
Verify Fault Code 3559 is active or inactive.
Locate OEM harness aftertreatment DEF dosing unit connector.
Pull up OEM harness wire cover on the backside of the aftertreatment DEF dosing unit
connector.
Check for loose weather pack seal (see Figures).
Resolution
See equipment manufacturer service information to repair or replace the aftertreatment DEF
dosing unit connector.
Document History
Date
2022-12-5
Details
Module Created
Last Modified: 07-Dec-2022
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1/5/23, 1:23 PM
Bosch® Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Unit Replacement for Fault Code 3559 Active/Inactive
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