Shown here: Pump module A 000 140 04 78 with repair solution, external pneumatic pressure reducing valve |
1 | Pump module |
2 | External pneumatic pressure reducing valve |
W14.40-1510-11
Shown here: Pump module A 000 140 05 78 with repair solution, internal pneumatic pressure reducing valve |
1 | Pump module |
12 | Internal pneumatic pressure reducing valve (type of construction: diaphragm valve) |
W14.40-1495-11
Pump module variants
Since the market launch of Euro 4/5, various pump module variants have been installed which differ with regard to their details and which can be distinguished by the part number attached to the housing.
Repair solutions for defective pressure reduction valves
Mechanical wear can result in pneumatic pressure reducing valves sticking. This leads to malfunctions in the exhaust aftertreatment system.
For some pump module variants there are repair solutions which avoid the need for replacement of the complete pump module if the pneumatic pressure relief valve becomes defective. Selection of a suitable repair method is available in the "AH14.40-W-0004-01A Overview for selecting suitable repair solution for defective pressure reduction valves for various pump module variants" document.
Troubleshooting/diagnosis
In the case of a fault, one of the following fault codes is currently stored in the engine control (MR) control unit:
MR X 67 70 "AdBlue®- pressure drop too low in power-down"
MR X 67 21 "AdBlue® pressure too low"
Depending on the software version of the engine control (MR) control unit the fault priority can be "X", "0" or "1".
The following causes can also lead to these fault codes:
Incorrect filling of AdBlue® tank with diesel fuel
Defective air pressure sensor on metering device
Kinked air lines or AdBlue® lines
Clogged filter screen
For this reason it is absolutely essential to adhere to the test steps specified in Star Diagnosis or in TIPS. If the instruction "Replace pump module" appears, the corresponding repair method should be used depending on the part number of the pump module (1).
Invoicing
The installation of the external/internal pneumatic pressure reducing valve can be invoiced using damage code 14471 B2 (AdBlue® pump module - clogged). Damage code 47308 (AdBlue® switching valve) has been introduced for complaints about the external/internal pneumatic pressure relief valve.
Parts ordering note |
Part no. | Designation | Quantity |
For pump modules with part numbers: A 000 140 05 78, A 000 140 09 78, A 000 140 15 78, A 000 140 25 78, A 000 140 27 78, A 000 140 44 78 | ||
A 000 142 00 19 | Internal pneumatic pressure relief valve | 1 |
For pump modules with part numbers: A 000 140 02 78, A 000 140 03 78 | ||
A 000 142 05 19 | External pneumatic pressure reducing valve | 1 |
A 003 997 23 89 | AdBlue® line plug connection 9.49 mm | 1 |
A 000 995 62 35 | One-ear clamp | 1 |
A 000 142 01 06 | AdBlue® filter | 1 |
A 941 475 17 20 | Profile base (as chafe protection for the external pneumatic pressure reducing valve) | 1 |
For pump modules with part number: A 000 140 04 78 | ||
A 000 142 03 19 | External pneumatic pressure reducing valve | 1 |
A 941 475 17 20 | Profile base (as chafe protection for the external pneumatic pressure reducing valve) | 1 |
Convert pneumatic pressure reducing valve of pump module | Only pump modules with one of the following part numbers: A 000 140 02 78, A 000 140 03 78, A 000 140 04 78 | ||
Remove and install internal pneumatic pressure relief valve on pump module | Pump modules with one of the following part numbers: A 000 140 05 78, A 000 140 09 78, A 000 140 15 78, A 000 140 25 78, A 000 140 27 78, A 000 140 44 78 |