105681-1150 ZEXEL 9 420 615 528 BOSCH AUTOM. ADVANCE MECHANISM 9420615528 1056811150 1685197112

Introduction
The problem identified below does not have a permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
There are reports of C4.4 DEF pumps failing in cold weather, below approximately −29° C (−20° F) , but the pumps are "No Fault Found" when returned for evaluation.Solution
Do not operate or work on this product unless you have read and understood the instruction and warnings in the relevant Operation and Maintenance Manuals and relevant service literature. Failure to follow the instructions or heed the warnings could result in injury or death. Proper care is your responsibility.
Ensure that the engine is stopped before any servicing or repair is performed. The Diesel Exhaust Fluid (DEF) system must have completed a proper shutdown. Service on the DEF pump prior to completion of a proper shutdown can result in DEF spray and spillage.
Do not turn off the battery disconnect switch until the indicator lamp has turned off. If the switch is turned off when the indicator lamp is illuminated, the Diesel Exhaust Fluid (DEF) system may not shut down properly. If the DEF system does not shut down properly, DEF could freeze and damage the pump and lines.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Cat Dealer Service Tool Catalog" or refer to Special Publication, PECJ0003, "Cat Shop Supplies and Tools Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Note: Clean water should be used to wash spilled DEF off machine components and surfaces.Note: Wear gloves when handling the DEF filter.When troubleshooting the DEF pump during cold weather, the Compensator Plug within the DEF pump is designed to prevent pump operation if the DEF within the pump is frozen. The Compensator Plug will temporarily be pushed to the OFF position by the frozen DEF. The pump should return to the ON position once the DEF thaws.
Illustration 1 g06278274
(1) Protective cover
Remove protective cover (1).
Illustration 2 g06278289
(2) DEF filter cap
Use a suitable tool to remove DEF filter cap (2).
Illustration 3 g06278325
(3) Compensator
With the filter installed in the DEF pump, carefully remove compensator (3).
Illustration 4 g06278356
(A) 38 mm (1.5 inch)
(B) 97 mm (3.8 inch)
Inspect the compensator.If frozen DEF within the pump is identified as the root cause of the issue, submit a SIMSi report, complete with TIB number M0094916, CPI number 411775 and submit through the CPI feedback tool within the SIMSi.