This guide describes replacing the factory front air vents with illuminated vent assemblies. The source identifies A-Class 176, B-Class 246, CLA 117 and GLA 156 with NTG 4.5 or NTG 5.0 head units. It describes single-color breathing and a 12-color breathing cycle. Coding is required after installation to enable color control through the instrument cluster on the small-screen NTG 4.5 configuration, or through the infotainment screen on the large-screen NTG 5.0 configuration.
The parts illustration shows a 2013–2018 A-Class W176 kit. The DIP-switch illustration also labels 2013–2018 A/B/CLA/GLA configurations. These illustrations do not establish every model-year, market or equipment combination; match the kit and control module to the vehicle configuration.
1. Parts shown
The source parts illustration labels:
- Five illuminated front air vents.
- A control module.
- The front-vent lighting harness.
- The module power harness.
Figure 1. Source kit illustration, headed “2013–2018 Mercedes-Benz A-Class W176” and “12-color front vents.”
2. Installation photo sequence
The installation photographs show a T30 driver for the door screws, a trim-prying tool and a pull hook for removing the vents. No driver size is specified for the screen or dashboard-panel screws.
- Remove the door's chrome trim and the door screws identified as T30 in the source photo.
- Pry up the side retaining clip at the marked location.
- Use a pull hook to remove all front vents. Engage the hook at the structural position circled in the close-up of the removed vent.
- Remove the screen mounting screws and take off the screen.
- The dashboard trim panel has both screws and retaining clips. Locate the clip through the left opening of the three center vents and remove the screw through the right opening, as marked in the photographs.
- Carefully pry up the dashboard trim panel, working from right to left.
- Route the illuminated-vent lighting harness along the path shown across the dashboard to the module in the right front door.
- Connect the vent module using the adapter connection at the right front door control unit's connector identified as “3#” in the source. This identifies the connector in the photograph; it is not a terminal or pin number.
Figure 2. The source installation sequence shows the door trim/T30 screws, side retaining clip, vent hook position, screen screws, center-panel retaining points, right-to-left panel removal, harness route and right front door control-unit connector “3#.”
The source describes replacing the complete vent assemblies. The photographs do not provide a complete connector pinout, electrical preparation procedure, harness fastening specification or step-by-step reassembly procedure.
3. Coding and controls
Small-screen configuration — NTG 4.5
The source specifies a Mercedes-Benz diagnostic computer for instrument-cluster coding on small-screen vehicles. Color selection is then controlled from the instrument cluster.
The coding screenshot highlights the instrument-cluster ambient-light menu entries, including “Ambientes Licht (Menu_Ambientlight)” and the ambient-light color menu entry. The illustrated setting is “vorhanden” (present). These are the entries shown in the source example; the complete coding procedure and applicable ECU/software versions are not supplied.
Figure 3. Small-screen illustration above an instrument-cluster variant-coding example with two ambient-light menu rows highlighted.
In the instrument cluster, follow Settings → Lighting → Ambient lighting. The source gives these steering-wheel button sequences:
- Single-color breathing: select Cool → Neutral → Cool, using Up → Down → Up.
- 12-color breathing cycle: select Warm → Neutral → Warm, using Down → Up → Down.
Figure 4. Instrument-cluster menu path and the Up/Down button sequences for the two breathing modes.
Large-screen configuration — NTG 5.0
For large-screen vehicles, the source gives two coding options: a Mercedes-Benz diagnostic computer or CheYiSheng OBD coding. Color selection is then controlled through the head unit.
The Mercedes-Benz diagnostic illustration includes these highlighted examples:
- Head unit: “Ambient Light” shown as on and “Color Ambient Light” shown as extended.
- Front SAM ambient-light channel: “PILC_AmBIEnable” shown as ja (yes).
- Ambient-light gateway channel: “Ambientes Licht vorhanden” shown as verfügbar (available).
These are source screenshot examples, not a complete coding recipe for every vehicle. Some hexadecimal strings are obscured by annotations in the original source; no complete coding string can be recovered from those images.
Figure 5. Large-screen diagnostic examples: the two head-unit lighting settings, the front SAM ambient-light channel and the ambient-light gateway channel.
The CheYiSheng OBD screenshot shows an A/B/CLA/GLA ambient-light coding feature, with 12 colors selected and 3 colors and Off also listed. It explicitly states that additional hardware must be installed before this feature is used. The screen includes Check current vehicle status and Apply these settings to the vehicle. The displayed feature ID and price belong to the archived screenshot; they do not establish present availability or pricing.
Figure 6. Source OBD coding example, including the required installed hardware, three options and the status-query/apply controls.
On the ambient-light color-selection screen, turn the vehicle's main rotary controller to change color. The source specifies:
- Single-color breathing: turn one detent counterclockwise → clockwise → counterclockwise (Left → Right → Left).
- 12-color breathing cycle: turn one detent clockwise → counterclockwise → clockwise (Right → Left → Right).
Figure 7. Ambient-light color wheel, main rotary controller and the one-detent direction sequences for breathing modes.
4. Troubleshooting
Color cannot be adjusted
Check the coding for the vehicle's configuration and check the vent control module's DIP-switch setting against the matching configuration in Figure 8.
The original table displays four unnumbered columns, read left to right:
| Source configuration | Displayed sequence, left to right |
|---|---|
| Small-screen, 2013–2018 A/B/CLA/GLA (117/176/156/246) | OFF · ON · OFF · ON |
| Large-screen, 2013–2018 A/B/CLA/GLA (117/176/156/246) | OFF · ON · ON · ON |
The table does not identify physical switch numbers or a viewing orientation. Confirm these against the supplied module instructions before mapping the four columns to physical switches. The small-screen row also mentions GLE/GLS 166/292; that shared row does not expand the vehicle scope of this front-vent guide.
Figure 8. Control-module DIP-switch location and the unnumbered four-column configuration table, followed by small-screen and large-screen reference photographs.
One vent shows a different color
Select red, green and blue, one after another, and check the basic colors. The source states that if one of these three colors is missing at a particular vent, that vent's light unit is faulty and needs replacement.
One vent is dim, but its colors still synchronize
The source identifies a light-guide tube broken during installation as a possible cause. It instructs replacing the affected dim illuminated vent.
All installed illuminated vents remain off
Check whether the ambient-light connector coming from the vent module is loose and whether the module's adapter connector is fully seated.