U0073 on Audi A4
Factory diagnostic protocol and troubleshooting wire for fault code U0073 specifically for the Audi A4 (2020–2026, 2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP)).
1. Symptoms of U0073 on Audi A4
When the Engine Control Module (ECM/PCM) on your Audi A4 (2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP)) logs fault code U0073, drivers commonly observe:
2. Most Likely Causes on Audi A4
Historical warranty claims and technical repair bulletins for Audi A4 point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Audi A4
Remove any aftermarket insurance dongles, GPS trackers, or scan tools plugged into the DLC port. on the Audi A4 equipped with 2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP).
Inspect braided ground straps on engine and transmission. Clean all contact surfaces to bare metal. on the Audi A4 equipped with 2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP).
Scan all modules on vehicle. Note which modules are online and which are offline to pinpoint the break in the network daisy-chain. on the Audi A4 equipped with 2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP).
Verify 60 ohms across Pins 6 and 14 with battery disconnected. on the Audi A4 equipped with 2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP).
Clear DTCs from all modules and road test to verify error-free network transmission. on the Audi A4 equipped with 2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP).
Equipment for Diagnosing Audi A4 (U0073)
Audi A4 OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for Audi A4.
AstroAI Auto-Ranging Digital Multimeter
Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.
BlueDriver Bluetooth Pro OBDII Scan Tool
Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.
Other Common Fault Codes on Audi A4
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Audi A4:
4. Audi A4 U0073 FAQs
What causes code U0073 to trigger on a Audi A4?
On the Audi A4 (2.0L TFSI Turbo 4-Cyl (EA888 Gen 4 201HP–261HP)), U0073 is most frequently caused by Loose or corroded ground connection on transmission or frame or Faulty Transmission Control Module (TCM) or ABS module pulling bus down.
Where is the OBD-II port located on my Audi A4?
On the Audi A4, the 16-pin DLC diagnostic connector is located Under driver side dashboard near hood release lever (pink/purple port). Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my Audi A4 with code U0073?
No. Bus is shut down due to excessive transmission errors, leaving vehicle in unpredictable limp mode. Given that U0073 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.