Fendt 1.2.30 – Engine Control Unit (EDC): B004 - Vacuum switch (air filter): Pressure loss above setpoint range

This code indicates that the engine's air filter is heavily contaminated or clogged. The restriction in the air intake creates excessive vacuum (underpressure) which triggers the B004 vacuum switch to alert the operator that the engine is struggling to draw in enough air.

• 411 Vario COM III
• 412 Vario COM III
• 413 Vario COM III
• 414 Vario COM III
• 415 Vario COM III
• 712 Vario COM III
• 714 Vario COM III
• 716 Vario COM III
• 718 Vario COM III
• 818 Vario COM III
• 820 Vario COM III
• 200 Vario Series
• 300 Vario Series (e.g., 309, 310, 311, 312)
• 400 Vario Series (e.g., 411, 412, 415)
• 700 Vario Series (e.g., 712, 714, 716, 718)
• 800 Vario Series (e.g., 818, 820 Greentec)
• 900 Vario Series (e.g., 916, 920, 924, 926, 930, 936)

1. 1

   Inspect the primary and secondary engine air filters for severe dust buildup, debris, or blockages

2. 2

   If the air filter is clean but the code persists, check the wiring to the B004 vacuum switch for breaks or short circuits (refer to OEM Wiring Diagram Sheet 35)

3. 3

   Connect the SERDIA / Fendias diagnostic tool to read out the specific KWP code and verify the sensor's live data

1. 1

   Locate air filter housing

   Open the engine hood and locate the air filter housing.

2. 2

   Inspect air filter elements

   Remove the primary (outer) air filter element and inspect the secondary (inner) safety element.

3. 3

   Clean or replace air filter

   Depending on the level of contamination, either blow out the primary air filter with compressed air (if permitted by the specific filter's guidelines) or replace the air filter elements entirely. Note: It is highly recommended to replace rather than clean to ensure optimal engine protection.

4. 4

   Replace B004 vacuum switch

   If the filter is new and the code remains, replace the B004 vacuum switch located on the air intake housing.

5. 5

   Clear fault code

   Connect the SERDIA diagnostic tool and clear the fault code (FC: 000B, 00F2) from the memory.