Replace Back Up Fog Light Bulb Mercedes-Benz 2014–2020 X156
Is the rear fog light and reverse light not working on your Mercedes-Benz GLA250? Learn how to fix the problem by replacing your vehicle’s light bulbs. This guide provides a step-by-step procedure for replacing the rear fog light and reverse (backup) light on the Mercedes-Benz GLA-Class. This tutorial is based on the 2017 GLA250 X156 chassis.
What you will need
- Prying tool
- 1235 light bulb
- 921 light bulb
Procedure
- Remove the trunk door panel. Click on this link to see the step-by-step procedure for removing and installing the trunk panel.

- Locate the rear and reverse fog light socket behind the inner tail light assembly.
- Remove the sockets by turning and pulling them out from the tail light assembly.
Removing the rear fog light socket. 
- Remove the rear fog light bulb from the socket by twisting it counterclockwise and pulling it out.

- Line up the new rear fog light bulb to the socket and twist it clockwise to lock it in place.

- Remove the reverse light from the socket by pulling it out. Then, line up the new reverse light to the socket and push it in to lock it into place.
- Reinstall the sockets back to the tail light assembly by pushing them in their original position.
- Reinstall the trunk panel. For more help with this step, see this guide.

We hope you find the Replace Back Up Fog Light Bulb Mercedes-Benz 2014–2020 X156 guide helpful. Check these troubleshooting and repair guides for more help on your Mercedes-Benz.
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Removing the rear fog light socket. 


