how do I fix the rear window defroster not working in my Toyota Corolla E170 (2013-2019)?

Toyota Corolla E170 (2013-2019)

Error Codes

1-2 hours

Time

medium

Difficulty

medium

Severity

3 min read

577 words

Problem Statement

Learn how to diagnose and fix the rear window defroster not working in Toyota Corolla E170 (2013-2019). Step-by-step guide with tools and parts required.

Affected Component

Electrical

Estimated Time

1-2 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical systems to prevent shock.
•Ensure the vehicle is turned off while inspecting any electrical components.

Symptoms

•Rear window defroster switch does not illuminate when activated
•No heat or defrosting effect on the rear windshield
•Possible blown fuse related to the defroster circuit
•Visible damage to defroster grid lines on the glass
•Intermittent operation or complete failure when activated

Diagnostic Steps

1
Inspect the rear window defroster switch for physical damage or wear.
2
Check for blown fuses in the fuse box related to the defroster circuit.
3
Use a multimeter to test the voltage at the defroster grid connectors.
4
Visually examine the defroster grid lines on the rear windshield for breaks or damage.
5
Verify the condition of the defroster relay by testing or swapping with a known working relay.
6
Inspect the wiring harness and connectors for corrosion or disconnection.

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

✓Test the affected component to ensure it functions correctly
✓Check for any error codes or warning lights
✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

•Follow the manufacturer's recommended maintenance schedule
•Address warning signs early before they develop into major issues
•Use quality parts and fluids recommended for your vehicle
•Keep detailed records of all repairs and maintenance

Tools & Equipment Required

•Multimeter
•Fuse puller or needle-nose pliers
•Defroster repair kit
•Alcohol wipes
•Cotton swabs

Parts Required

•Replacement fuse
•Replacement relay
•Defroster grid repair paint

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Inspect the rear window defroster switch for physical damage or wear.
2
Check for blown fuses in the fuse box related to the defroster circuit.
3
Use a multimeter to test the voltage at the defroster grid connectors.
4
Visually examine the defroster grid lines on the rear windshield for breaks or damage.
5
Verify the condition of the defroster relay by testing or swapping with a known working relay.
6
Inspect the wiring harness and connectors for corrosion or disconnection.

Solution

1. Preparation

Gather necessary tools and parts.
Ensure the vehicle is parked on a level surface and the ignition is off before starting any repairs.
Disconnect the negative battery terminal to prevent electrical shock.

2. Check and Replace Fuse

Tools Required: Fuse puller or needle-nose pliers
Locate the fuse box under the dashboard or in the engine compartment.
Identify the fuse linked to the rear window defroster (refer to the owner's manual for fuse location).
Remove the fuse and inspect it for continuity; if blown, replace it with a new fuse of the same amperage.

3. Inspect and Repair Defroster Grid

Tools Required: Defroster repair kit (if grid lines are damaged), alcohol wipes, and cotton swabs
Clean the area around the damaged grid lines with alcohol and cotton swabs.
If there are breaks in the grid lines, use the defroster repair kit to apply conductive paint or adhesive over the damaged areas according to the manufacturer’s instructions.
Allow adequate drying time as specified in the repair kit instructions.

4. Test and Replace Relay (if necessary)

Tools Required: Multimeter, replacement relay if needed
Locate the defroster relay in the fuse box.
Use a multimeter to check for continuity in the relay. If no continuity is found, replace the relay with a new one of the same specifications.

5. Reconnect Battery

Reattach the negative battery terminal securely.
Ensure all tools are removed from the engine compartment and the vehicle is safe for testing.