The source lists model years 2019–2024 for these vehicles. The illustrated installation uses an A-Class with factory ambient lighting. The parts photograph is labelled 2019–2022 A-Class W177, so it does not demonstrate fitment for every model/year in the broader source description. Confirm the actual vent assembly, vehicle equipment and lighting-kit version before installation.
The source describes colour synchronization, multicolour and breathing effects, and installation without programming for a matching product. It also specifies different connections for factory lighting, certain imported AMG vehicles and aftermarket lighting. Identify which system is installed before selecting a harness or lamp head.
1. Parts overview
The photograph shows two rear vents, two chrome trim rings and a vent-lighting harness. A visible tag on the pictured harness includes “205”; the photograph alone does not confirm the harness version for the listed vehicles. Use the version confirmed for the vehicle's lighting system. The three-wire and four-wire versions are distinguished later in this guide.
2. Illustrated installation: A-Class with factory ambient lighting
Read the photographs from top to bottom:
- Open the centre-armrest storage compartment shown, then use a trim tool to release the rear vent panel assembly at the illustrated edge. This is the storage compartment beside the rear console panel, rather than the dashboard glovebox.
- Release the marked concealed clips at the front of the original vent mounting arrangement.
- Release the marked concealed clips at its sides and remove the original rear vents.
- Remove the original outer trim rings.
- Fit the illuminated replacement vents, aligning the side locating pins marked in the photograph.
- Fit the replacement trim rings, aligning their locating features with the vents as shown.
- Locate the ambient footwell light beneath the seat shown.
- Disconnect that light's original connector.
- Connect the matching adapter plugs as illustrated. The final source caption instructs trimming the marked plastic locating/keying projection on the white connector. This refers to the plastic housing feature, not an electrical terminal. Confirm that this precise connector modification is specified for the actual kit and vehicle before altering the housing; a plug that can be made to fit is not proof of electrical compatibility.
The photographs do not show a complete rear-to-front harness route, securing clearances, panel refitting or final function checks. They also do not establish a common trim-release direction for all five listed vehicle models.
3. Troubleshooting and lighting-system selection
No light: check the product version
If the rear vent lights do not illuminate, the source's first check is whether the product matches the vehicle model and ambient-light configuration.
The left harness in this photograph is labelled for factory ambient lighting. It has dedicated footwell-light adapter connectors and three-wire lamp-head connectors with a factory-protocol chip, according to the source label. The right harness is labelled for aftermarket ambient lighting, with standard ambient-light adapter connectors and ordinary four-wire RGB lamp-head connectors. The source's “RBG” lettering is a channel-order typo; its subsequent table identifies red, green and blue channels.
These labels distinguish the illustrated product versions. Wire count or connector colour alone does not identify the actual protocol or prove that a particular harness is compatible.
White light only: check the doors and cabin-light setting
Close all four doors, or switch off the cabin/roof-light control shown, and check whether the ambient colour operation returns. If the rear vent light remains white with the doors closed, the source identifies a mismatched lamp-head program as a possible product-version issue and instructs replacing it with a matching lamp head.
The picture shows the roof control used for this check. Its caption refers to white-only seat/footwell ambient lighting, which is the lighting source used in the illustrated factory installation. It does not show a rear-vent fault test. Confirm the wiring and matching lamp-head version before treating white-only light as a conclusive diagnosis.
Factory ambient-light version
For the product matched to factory ambient lighting, the source specifies connection to the footwell ambient-light circuit beneath the seat serving the rear seating area. It explicitly says not to connect this version at other locations. This is the factory-lighting example; the imported-AMG and aftermarket branches below use different arrangements.
Imported AMG exception
For imported A35, A45 and GLB AMG examples, the source specifies a module connected at a door and ordinary lamp heads because it describes a different factory lighting protocol. The following photo identifies the front-right door and connector No. 3 on its door control module.
- Identify the illustrated front-right door control module and its connector No. 3.
- Use the matching module adapter connection shown at that connector. “No. 3” identifies the connector, not terminal cavity 3.
- Insulate/wrap the reserved unused plug identified in the photograph.
This illustration does not supply the adapter module model, connector pinout, complete door-to-rear-console wire route or a confirmed market/year compatibility list. Do not assume that every AMG vehicle uses this connection.
Aftermarket ambient-light version
The source specifies joining the rear-vent lighting harness to the front-vent lighting harness for synchronized colours. The following access photographs show the front vent panel:
- Remove the two T20 screws marked below the climate-control panel.
- Use two small flathead screwdrivers at the marked positions to release the concealed clips, as shown.
- Release and remove the front vent panel with a trim tool.
The source does not illustrate the full aftermarket splice/adapter connection or harness route. Confirm the actual front/rear lamp-head channel assignments before connecting them.
Example wire-colour mapping for differing aftermarket harnesses
The source gives the following mapping for the particular CKCP and other-brand harnesses illustrated. It is an example from this tutorial, rather than a universal wiring standard for all products or vehicles.
| CKCP lamp-head wire/function in the source | Other-brand harness wire in the example |
|---|---|
| Yellow — positive | Yellow |
| Red — red light channel | Green |
| Green — green light channel | White |
| Blue — blue light channel | Red |
The photograph labels the two sides “Ours” and “Others.” The text identifies yellow as positive but gives no rated voltage, ground/common-return definition, connector cavity numbers or joining method. Confirm those electrical details for the actual lighting system; do not infer them from colour or transfer this four-wire RGB example to the three-wire factory-protocol version.
The source does not provide a complete refitting, diagnostic or final acceptance procedure. Colour synchronization, multicolour and breathing effects are described capabilities; their operation on the actual vehicle still needs to be checked after the correct product and connections have been confirmed.