Further action is required depending on the respective degradation phases. This action is listed under the respective degradation phase. To assess the degradation phases, refer to the document AH20.00-N-0002-01H Notes on assessment of degradation phases of coolant sludging.
Degradation phase 1
The retarder must be checked for internal leak tightness and, if necessary, replaced (see document AR43.30-W-0048WR).
If the retarder is replaced, the software release in the retarder control unit (RCM) and in the instrument cluster control unit (ICUC) must be updated (see document SI43.30-W-0021WR). In addition, a retarder characteristics map adaptation must be performed. The retarder characteristics map adaptation is completely menu-assisted under: Special functions Retarder characteristics map adaptation.
The coolant must be replaced.
The coolant filter element must be replaced and the filter housing must be freed from sludge (only on vehicles with code M8T (Coolant filter)).
The residual heat pump must be replaced (only for vehicles with code D6I (Residual heat utilization) up to vehicle identification end number 0010278, if, upon disconnection of the residual heat pump electrical connector, coolant residue indicates a leakage).
Degradation phase 2
The retarder must be checked for internal leak tightness and, if necessary, replaced (see document AR43.30-W-0048WR).
If the retarder is replaced, the software release in the retarder control unit (RCM) and in the instrument cluster control unit (ICUC) must be updated (see document SI43.30-W-0021WR). In addition, a retarder characteristics map adaptation must be performed. The retarder characteristics map adaptation is completely menu-assisted under: Special functions Retarder characteristics map adaptation.
The coolant must be replaced.
The engine cooling system must be flushed.
The heater core must be flushed with water opposite the direction of flow. This is done via the fitting (return line) on the left, as viewed from the direction of travel, until clear water is discharged.
The radiator must be flushed with water until clear water is discharged.
The coolant expansion reservoir must be replaced.
The front coolant expansion reservoir with coolant pressure regulation solenoid valve must be modified (only for engine 470.9, 471.9 without codeD6H (stationary air conditioning system) see document SM20.30-W-0006A).
The coolant filter must be retrofitted (only on vehicles without code M8T (Coolant filter) and on vehicles for which the installation instructions for retrofitting the coolant filter (see document SI20.00-W-0005A) are valid).
The coolant filter element is to be replaced 4 to 8 weeks after its installation.
The coolant filter element must be replaced and the filter housing must be freed from sludge (only on vehicles with code M8T (Coolant filter)).
The coolant filter element is to be replaced after 4 to 8 weeks.
The residual heat pump must be replaced (only for vehicles with code D6I (Residual heat utilization) up to vehicle identification end number 0010278, if, upon disconnection of the residual heat pump electrical connector, coolant residue indicates a leakage).
Degradation phase 3/4
The coolant must be replaced.
The engine cooling system must be flushed.
The coolant expansion reservoir must be replaced.
The front coolant expansion reservoir with coolant pressure regulation solenoid valve must be modified (only for engine 470.9, 471.9 without codeD6H (stationary air conditioning system) see document SM20.30-W-0006A).
Retarders up to manufacturing date 16W20
Retarders up to manufacturing date 16W20 must always be replaced. In addition, the screw of the retarder side channel pump must be checked to ensure that it is present (see document AR43.30-W-0054WR, operation steps 4 to 6).
Retarders as of manufacturing date 16W20
Retarders as of manufacturing date 16W20 must be checked for internal leak tightness as per AR43.30-W-0048WR.
If the retarder is leaktight internally, it remains in the vehicle.
If the retarder is not leaktight internally, it must be replaced. In addition, the screw of the retarder side channel pump must be checked to ensure that it is present (see document AR43.30-W-0054WR, operation steps 4 to 6).
The manufacturing date of the retarder is specified on the identification plate and consists of both the production year and the production week (e.g. for production week 18 in production year 2016: 16W18).
If the retarder is replaced, the software release in the retarder control unit (RCM) and in the instrument cluster control unit (ICUC) must be updated (see document SI43.30-W-0021WR). In addition, a retarder characteristics map adaptation must be performed. The retarder characteristics map adaptation is completely menu-assisted under: Special functions Retarder characteristics map adaptation.
The coolant filter must be retrofitted (only on vehicles without code M8T (Coolant filter) and on vehicles for which the installation instructions for retrofitting the coolant filter (see document SI20.00-W-0005A) are valid).
The coolant filter element is to be replaced 4 to 8 weeks after its installation.
The coolant filter element must be replaced and the filter housing must be freed from sludge (only on vehicles with code M8T (Coolant filter)).
The coolant filter element is to be replaced after 4 to 8 weeks.
The radiator must be replaced.
The heater core must be replaced.
All coolant-carrying hoses must be replaced.
Main coolant hoses between engine, cooler and retarder
Filling coolant hose, from coolant expansion reservoir to oil/coolant module
Bleed lines at radiator, EGR cooler/engine and at retarder line
Coolant hoses of residual heat pump (the residual heat utilization pump is replaced, as this is a parts kit)
Coolant hoses for heating and auxiliary heating
Hoses to coolant pressure regulation solenoid valve (Y53)
Coolant lines of AdBlue® heater
Retarder locking pressure line (return line)
Coolant hoses at coolant feed pipe to exhaust gas recirculation cooler (only on engine 470.9)
Coolant hoses of coolant filter (only for vehicles with code M8T (Coolant filter))
Invoicing
Use the following damage codes when submitting operations relating to sludging of the coolant:
For models WDF963.### #B up to 984696, WDB963.### #0 up to 074767, WDB964.### #0 up to 074767, WDB963.### #L up to 999999, WDB964.### #L up to 999999, NMB963.### #2 up to 180092, NMB964.### #2 up to 180092
In degradation phase 1 Damage code 20035 ZZ
In degradation phase 2 Damage code 2012D ZZ
In degradation phase 3/4 Damage code 2012G ZZ
For models WDF963.### #B as of 984697, WDB963.### #0 as of 074768, WDB964.### #0 as of 074768, NMB963.### #2 as of 180093, NMB964.### #2 as of 180093
In deficiency phase 1 Damage code 20035 01
In deficiency phase 2 Damage code 2012D 01
In degradation phase 3/4 Damage code 2012G 01
If the retarder is OK, the test work of the retarder, in combination with sludging of the coolant (deficiency phase 1-4), must be submitted using damage code 43601 02.
If the retarder is defective, the test work and replacement of the retarder, in combination with sludging of the coolant (deficiency phase 1-4), must be submitted using the corresponding standard damage codes of the retarder.
Note: In this special exception instance (i.e. sludging of the coolant) - in contrast to the Warranty Manual article WR 02-01-190 - the coolant may also be submitted with any incurred customer parts using the Warranty & Goodwill application.