2014 to 2020 Mercedes Benz Side Turn Mirror Signal Replacement
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Is your Mercedes-Benz GLA-Class side mirror broken? This guide is a step-by-step instruction on how to replace the side mirror for a Mercedez-Benz GLA250. It can be applicable o other models because Mercedes-Benz uses the same turn signal (blinker) design.
At a Glance
- Vehicle: 2014 to 2020 Mercedes-Benz GLA (GLA250 shown); similar on many models
- Tools: Prying tool, T10 Torx screwdriver
- Key step: Pry the mirror glass off carefully and unplug the heater, blind spot and signal connectors
- Part: The LED turn signal is replaced as a unit
- Time: About 30 minutes
Mirror Turn Signal Problems
- Mirror signal dark but the front signal works: the LED unit in the mirror or its connector has failed. The LED strip is replaced as a unit.
- Fast flashing: the car has detected a failed bulb or LED on that side.
- Works intermittently: check the connector behind the mirror glass and the wiring where it passes into the door.
- Dash warning for a turn signal lamp: confirms an open circuit on that side.
A scan tool such as the YOUCANIC UCAN-II Pro can read door and lighting module codes on supported models to confirm which circuit has failed.
What you will need
- Prying Tool
- T10 Screwdriver
- Side Mirror for Mercedes-Benz
- A 156 810 29 00 (Driver Side)
Procedure
- Use a prying tool to detach the side mirror from the cover housing.
- Disconnect the electric connector for the blind spot sensor, heated mirror, and blinker.
Pull off the blind spot sensor connector.
- Once all the connectors are removed, you can now dismantle the housing cover.
- Remove the screws using a T10 screwdriver and push up the led blinker light bulb
- Put the new led bulb tab and snap it to the lower piece of the side mirror mount.
- Attach the lower housing piece and snap the front and back side tabs into place to hold it
- Snap all the removed connectors and screws to lock it. Do not forget to hook on the blue connector. Use the T10 screwdriver.
- Put back the side mirror shield, and make sure the blinker is connected.
- Install the side mirror glass by hooking the two connectors for the heated mirror and blind spot sensor; once mounted, snap it into place.
Replacing the mirror housing and turn signal on a Mercedes-Benz is easy and can be done at home. The cost to replace the mirror turn signal is $50 to $200, depending on where you purchase the replacement turn signal.
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Check these troubleshooting and repair guides for more help on your Mercedes-Benz.
Frequently Asked Questions
How do I replace the mirror turn signal on a Mercedes GLA?
Pry off the mirror glass, unplug its connectors, remove the housing cover, then remove the T10 screws and swap the LED turn signal unit.
Can I replace just the LED in the mirror signal?
No. The LED turn signal is replaced as a complete unit.
Why is my Mercedes turn signal flashing fast?
A failed bulb or LED on that side, including the mirror signal, makes the system flash faster.
Will removing the mirror glass damage it?
Not if you go slowly. Pry evenly from the edge and support the glass while unplugging the connectors.
Related Guides
- Replace Front Turn Signal Light Bulb Mercedes-Benz GLA-Class 2014 to 2019
- Replace Tail Light Assembly & Signal Light Mercedes-Benz 2014 to 2019 X156
- Mercedes-Benz How to Turn On Emergency Lights
- How to Mirror Phone Display to Mercedes COMAND Screen
