🚗 How to Install Fog Lights on a Toyota Yaris (Step-by-Step Guide)
Difficulty: ⭐⭐☆☆☆ Beginner–Intermediate
Estimated Time: 1–2 Hours
Vehicle: Toyota Yaris (Factory Pre-Wired)
Tools Required: Basic Hand Tools
Installing factory-style fog lights on your Toyota Yaris is a great upgrade that improves visibility in fog, rain, and at night while giving the front bumper a cleaner OEM appearance.
If your Yaris is already pre-wired for fog lights, this installation is much easier because most of the wiring is already in place.
📑 Table of Contents
- Tools You’ll Need
- Step 1 - Remove the Fog Light Blank
- Step 2 - Access the Inside of the Bumper
- Step 3 - Install the Fog Lights
- Step 4 - Connect the Factory Wiring
- Step 5 - Install the Fog Light Switch
- Step 6 - Test the Fog Lights
- Troubleshooting
🧰 Tools You’ll Need
- ✅ Screwdriver
- ✅ Socket wrench or ratchet
- ✅ Fog light kit
- ✅ Relay
- ✅ Fuse
- ✅ Wiring connectors (if required)
Step 1 - Remove the Fog Light Blank
Begin by removing the fog light blank, which is the plastic cover in the front bumper where the fog light will be installed.
Tip
Use a plastic trim removal tool if possible to avoid scratching the bumper.
Warning
Do not force the plastic clips. They can easily break.
Step 2 - Access the Inside of the Front Bumper
To reach the fog light mounting area:
- Remove the screws from the left and right sides of the underbody cover.
- Carefully pull the underbody cover toward one side.
- Move it just enough to access the inside of the bumper.
Tip
There’s no need to remove the entire splash shield.
Step 3 - Install the Fog Lights
Inside the bumper, you’ll find:
- Two mounting holes for the fog light.
- One locating hole for the plastic alignment tab.
Installation:
- Insert the plastic locating tab.
- Align the fog light.
- Tighten the mounting screws.
Repeat the same process on the opposite side.
Figure 1. Body Control Unit.
Step 4 - Connect the Factory Wiring
Each side of the bumper already has a factory connector.
Simply:
- Locate the pre-wired connector.
- Plug it into the fog light.
- Ensure the connector clicks into place.
Note
Check both connectors before reinstalling the under cover.
Figure 2. Fog light fuse location.
Step 5 - Install the Fog Light Switch
Move inside the driver’s seat.
- Remove the lower dashboard cover.
- Locate connector
D160. - Find pins
D3andD4. - Connect wires to
D3andD4. - Remove the dashboard switch blank.
- Route the wires to the switch opening.
- Install the relay and fuse (if your kit requires them).
- Connect the fog light switch.
Important
Verify your fog light kit includes the correct relay and fuse before installation.
Figure 3. Connector D160 and pins D3 / D4.
Step 6 - Test the Fog Lights
Before reinstalling all panels:
- Turn on the parking lights.
- Verify the fog light switch illuminates.
- Press the switch.
- Confirm both fog lights turn on.
If everything works correctly:
- Reinstall the underbody cover.
- Tighten all screws.
- Reinstall the dashboard trim.
Figure 4. Fog lights operating normally.
🔧 Troubleshooting
If the fog lights don’t work, check the following:
| Item | Check |
|---|---|
| Factory Connector | ✅ Fully connected |
| Fuse | ✅ Installed |
| Relay | ✅ Installed |
Pin D3 |
✅ Correct |
Pin D4 |
✅ Correct |
| Switch | ✅ Connected |
| Bulbs | ✅ Working |
Figure 5. Fog light indicator on the dashboard.
✅ Final Thoughts
Installing OEM-style fog lights on a Toyota Yaris is one of the easiest upgrades if your vehicle is already factory pre-wired.
Before putting everything back together, make sure to:
- ✅ Check every connector.
- ✅ Verify the relay and fuse.
- ✅ Test both fog lights.
- ✅ Confirm the dashboard indicator works correctly.
Enjoy your new fog lights and drive safely!