U04A9 on Volkswagen vehicles

A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.

Bulletins and campaigns Volkswagen filed with NHTSA whose summary names U04A9. Quote the document number at the service desk — it is a diagnosis the maker has already written down.

• VIN4APIN2024731 Other
  2024-07-31 · Unknown Or Other
• Customer states rattle from below the vehicle; Customer states MIL-on, P0442 stored in ECM memory; Customer states key FOB lock/unlock functions do not work via button press (not KESSY); Customer states seat belt won't retract; Customer states door fitment between panels not correct; Customer states windshield has a visual imperfection, Customer states Electrical System Error Message, U04A1 [42304
• VIN4APIN20240807 Other
  2024-08-07 · Unknown Or Other
• Customer states rattle from below the vehicle; Customer states MIL-on, P0442 stored in ECM memory; Customer states key FOB lock/unlock functions do not work via button press (not KESSY); Customer states seat belt won't retract; Customer states door fitment between panels not correct; Customer states windshield has a visual imperfection, Customer states Electrical System Error Message, U04A1 [42304
• VIN4APIN2024814 Other
  2024-08-14 · Unknown Or Other
• Customer states rattle from below the vehicle; Customer states MIL-on, P0442 stored in ECM memory; Customer states key FOB lock/unlock functions do not work via button press (not KESSY); Customer states seat belt won't retract; Customer states windshield has a visual imperfection, Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] stored in DA:008C;
• VIN4APIN20250113 Other
  2025-01-13 · Unknown Or Other
• Customer states MIL-on, P0442 stored in ECM memory; Customer states the seat cover has discoloration (usually yellowing) stains; Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] stored in DA:008C; Customer states vehicle does not start; key not detected. No communication to J519 active. AW 19: U014000[2170894][2240526], B1248F3[1074443], U17B900[
• VIN4APIN20250121 Other
  2025-01-21 · Unknown Or Other
• Customer states MIL-on, P0442 stored in ECM memory; Customer states MIL-on, P0068 stored in ECM memory; Customer states the seat cover has discoloration (usually yellowing) stains; Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] stored in DA:008C; Customer states vehicle does not start; key not detected. No communication to J519 active. AW 19: U0
• VIN4APIN20250129 Other
  2025-01-29 · Unknown Or Other
• Customer states MIL-on, P0442 stored in ECM memory; Customer states MIL-on, P0068 stored in ECM memory; Customer states the seat cover has discoloration (usually yellowing) stains; Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] stored in DA:008C; Customer states vehicle does not start; key not detected. No communication to J519 active. AW 19: U0
• VIN4APIN20241121 Other
  2024-11-21 · Unknown Or Other
• Customer states rattle from below the vehicle; Customer states coolant leak/coolant light on; Customer states MIL-on, P0442 stored in ECM memory; Customer states key FOB lock/unlock functions do not work via button press (not KESSY); Customer states the seat cover has discoloration (usually yellowing) stains; Customer states MIL-on, U01B000 stored in ECM memory; Customer states seat belt won't ret
• VIN4APIN20250423 Other
  2025-04-23 · Unknown Or Other
• Customer states MIL-on, P055F stored in ECM memory with message on cluster stating “please warm engine oil to 176 degrees F”; Customer states MIL-on, P0442 stored in ECM memory; Oil leak from Cylinder Head Cover; Customer states MIL-on, P0087 Stored in ECM memory; Customer states key functions (FOB or KESSY) for lock and/or unlock are inoperative; Customer states Electrical System Error Message, U
• VIN4APIN20250528 Other
  2025-05-28 · Unknown Or Other
• Customer states MIL-on, P055F stored in ECM memory with message on cluster stating “please warm engine oil to 176 degrees F”; Oil leak from Cylinder Head Cover; Customer states MIL-on, P0087 Stored in ECM memory; Customer states key functions (FOB or KESSY) for lock and/or unlock are inoperative; Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] st
• VIN4APIN20250605 Other
  2025-06-05 · Unknown Or Other
• Customer states MIL-on, P055F stored in ECM memory with message on cluster stating “please warm engine oil to 176 degrees F”; Oil leak from Cylinder Head Cover; Customer states MIL-on, P0087 Stored in ECM memory; Customer states key functions (FOB or KESSY) for lock and/or unlock are inoperative; Customer states windshield wipers activate (swipe) on their own without rain input; Customer states El
• VIN4APIN20250818 Other
  2025-08-18 · Unknown Or Other
• Oil leak from Cylinder Head Cover; Customer states MIL-on, P0456, P0442, or P04F0 stored in ECM memory; Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] stored in DA:008C; Customer states wind noise and or water ingress; Customer states middle row seat rattles; Customer states there is a noise coming from the front strut arae; Customer states ther
• VIN4APIN20250910 Other
  2025-09-10 · Unknown Or Other
• Oil leak from Cylinder Head Cover; Customer states MIL-on, P0456, P0442, or P04F0 stored in ECM memory; Customer states Electrical System Error Message, U04A1 [42304], U04A5 [42336], and/or U04A9 [42444] stored in DA:008C; Customer states wind noise and or water ingress; Customer states there is a noise coming from the front strut arae; Customer states there is a noise coming from the front strut

A stored code names the test that failed, never the part that caused it. The record above is what Volkswagen and its owners have filed about it; the code’s page across every make has the whole file.