5A73

What the code means

Code 5A73 points to incorrect voltage in the shift paddle circuit of the DCT dual-clutch transmission. The transmission control unit (TCU) monitors the voltage signal from the paddles; a deviation from spec indicates a wiring problem, a faulty paddle, or the TCU itself throwing an error.

Symptoms

• Shift paddles don't respond when pressed
• Transmission won't shift in manual mode
• A fault indicator lights up on the instrument cluster

Diagnostics and repair

Step 1

Read the TCU codes with INPA or ISTA diagnostic equipment.

Step 2

Check the shift paddle wiring and connector for damage, corrosion, or breaks.

Step 3

Measure paddle resistance with a multimeter — it should match the manufacturer's spec.

Step 4

If you find a fault, replace the faulty paddle or repair the damaged wiring.

Secondary issues

Ignoring the fault can leave the transmission running in automatic mode only, locking the driver out of manual shifting. No significant secondary damage is expected.