Audi RNS-E Code Guide

The Audi RNS-E is one of the most popular factory navigation units ever fitted to a German car. Found in the A3 (8P), A4 (B6 and B7), A6 (C6), TT (8J) and several other models from around 2004 to 2009, it uses the same power-loss locking mechanism as the Concert and Symphony head units — but retrieving the serial requires a slightly different approach. If your RNS-E displays SAFE or CODE, this guide walks you through the whole process.

Why the RNS-E Locks After a Battery Change

Like all VAG-group units of its era, the RNS-E monitors its permanent 12-volt supply. Any interruption — a flat battery, a replaced battery, or even a brief disconnect during electrical work — triggers the lock. The unit freezes the navigation, radio and DVD functions until the correct four-digit code is entered. The code is unique to each unit's AUZ serial number.

Finding the RNS-E Serial Number

The RNS-E does not respond to the standard 1+6 preset trick used by Concert and Symphony units. Instead, use one of these methods:

Hidden menu: Switch the ignition on. On the RNS-E front panel, press and hold the Setup button, then press the Return/Back button. On some firmware versions you press and hold Setup until a diagnostic screen appears. Navigate to Unit Information or Device Info — the serial number is displayed here as a 14-character string starting with AUZ.
Unit extraction: Use DIN extraction hooks (four metal keys) to slide the unit out of the double-DIN slot. The white barcode label on the top or side of the casing carries the full AUZ serial.

Note the serial in full — every character including any hyphens or internal slashes. Serial prefixes used across the RNS-E range include AUZ and occasionally SEZ on factory-retro-fit units.

Getting and Entering Your Code

With the serial in hand, head to our Audi brand page to order. Once you receive the four-digit code by email:

Switch ignition on (engine off).
Confirm the screen shows CODE or the 1 0 0 0 entry display.
Use the four preset/function buttons along the bottom of the screen (or the rotary joystick on some firmware builds) to set each digit in turn.
Press OK or the right arrow/joystick push to confirm. Navigation and radio resume immediately.

RNS-E Variants and Compatible Vehicles

Variant	Typical Fit	Years	Notes
RNS-E Mk1	A3 8P, A4 B6/B7, TT 8N/8J	2004–2007	DVD map disc; AUZ serial
RNS-E Mk2	A3 8P facelift, A4 B7 late, A6 C6	2006–2009	Updated firmware; same AUZ serial system
RNS-E Plus	A4 B8 early, Q5 8R early	2008–2010	Some units are VIN-bound post-facelift

OEM manufacturers for the RNS-E include Harman and Philips. The unit is double-DIN in size and its distinctive silver bezel with large rotary joystick makes it easy to identify.

Troubleshooting

SAFE on screen, hidden menu is blank: Some units require ignition position II and a 30-second warm-up before the diagnostic screen populates. Try again after waiting.
WAIT: A wrong code has been entered. Wait the displayed number of minutes (usually 60) before attempting again.
CODE 1000: Normal starting position for entry. Not an error — use the preset buttons to dial your code.
Serial starts with something other than AUZ: A small number of retrofit RNS-E units carry an SEZ prefix — this is still supported.
Unit shows LOCKED after many wrong codes: This is a timed lock, not permanent. After the full wait period the unit will return to CODE mode.

Frequently Asked Questions

Is the RNS-E code the same as the Concert/Symphony code for the same car?

No. Each unit has its own serial and its own unique four-digit code. If you replace an RNS-E with a Concert, the Concert needs its own code obtained from its own serial.

My RNS-E has been retrofitted from a different car — will the code still work?

Yes. The code is tied to the unit's serial number, not the vehicle's VIN. As long as you have the correct AUZ serial from the unit itself, the code will work regardless of which car it is now installed in.

Does the RNS-E need a code after every battery change?

Yes, every power interruption triggers the lock. Storing the code in your vehicle documents means future unlocks take under a minute.

Can I enter the code via the touchscreen?

The RNS-E does not have a touchscreen — it uses physical preset buttons and a rotary joystick. Entry is via those controls only.

What if I cannot find the serial anywhere on the unit or in the menu?

If the diagnostic menu is inaccessible and the unit is already locked (preventing any menu access), physical extraction and label reading is the only remaining option. A trim removal tool and DIN extraction keys are all that is needed.