AutoCodes – Mercury – B1349 Mercury

B1349 Mercury Code - Heated Backlite Relay Short to Battery

Quick Answer

When the rear defrosts switch on the climate control assembly is pressed, a ground signal is sent to the Smart Junction Box (SJB) on the circuit. Common causes include Faulty Heated Rear Window Relay, Faulty Heated Rear Window Switch, Faulty Heated Rear Window Grid. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B1349 Mercury indicates Heated Backlite Relay Short to Battery.
Common causes: Common causes include Faulty Heated Rear Window Relay, Faulty Heated Rear Window Switch, Faulty Heated Rear Window Grid.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 781

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 15, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B1349 Mercury Description

When the rear defrosts switch on the climate control assembly is pressed, a ground signal is sent to the Smart Junction Box (SJB) on the circuit. The SJB then grounds circuit. This energizes the heated rear window relay, allowing voltage to be supplied to the heated rear window grid through the circuit. The OBDII code sets when the Heated Backlite Input is not to factory specifications.

OBDII Code B1349 Mercury - Heated Backlite Relay Short to Battery - AutoCodes.com — B1349 Mercury Code - Heated Backlite Relay Short to Battery

What does this mean?

What are the Possible Causes of the DTC B1349 Mercury?

Faulty Heated Rear Window Relay
Faulty Heated Rear Window Switch
Faulty Heated Rear Window Grid
Faulty Smart Junction Box (SJB)

How to Fix the DTC B1349 Mercury?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1349 Mercury code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the B1349 Mercury code?

Need more information on how to fix the B1349 Mercury code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1349 Mercury code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B1349 Mercury Code

1. What are the common symptoms of OBDII code B1349 (Heated Backlite Relay Short to Battery) in a Mercury vehicle?

The common symptoms include the rear defroster not working, visible damage to the wiring or relay, and a blown fuse related to the heated backlite system.

2. What are the possible causes of OBDII code B1349 in a Mercury vehicle?

The typical causes of B1349 include a short circuit in the wiring, a malfunctioning relay, a damaged backlite grid, or a faulty control module.

3. How can I diagnose OBDII code B1349 in my Mercury vehicle?

You can diagnose B1349 by visually inspecting the backlite wiring, checking the relay for proper operation, testing the backlite grid for continuity, and using an OBDII scanner to retrieve the code.

4. What is the recommended repair for OBDII code B1349 in a Mercury vehicle?

The recommended repair for B1349 involves repairing any damaged wiring, replacing a faulty relay, repairing the backlite grid if damaged, or replacing a malfunctioning control module.

5. Can I drive my Mercury vehicle with OBDII code B1349 (Heated Backlite Relay Short to Battery) present?

It is not recommended to drive your vehicle with code B1349 present, as the rear defroster may not function properly, especially in cold or rainy conditions.

6. How much does it typically cost to repair OBDII code B1349 in a Mercury vehicle?

The cost of repairing B1349 can vary depending on the specific cause, but it may range from $100 to $300 for parts and labor.

7. Is OBDII code B1349 a serious issue in a Mercury vehicle?

While B1349 is not a critical safety issue, it can affect the functionality of the rear defroster, which is important for visibility in certain weather conditions.

8. Can I reset OBDII code B1349 in my Mercury vehicle by disconnecting the battery?

Disconnecting the battery may clear the code temporarily, but it is not a recommended long-term solution. It is best to diagnose and repair the underlying issue causing the code.

9. Will OBDII code B1349 cause my Mercury vehicle to fail an emissions test?

B1349 is not directly related to emissions, so it may not cause your vehicle to fail an emissions test. However, it is still important to address and repair the issue.

10. How can I prevent OBDII code B1349 from recurring in my Mercury vehicle?

To prevent B1349 from recurring, you should regularly inspect the wiring and components of the heated backlite system, address any issues promptly, and follow the manufacturer's maintenance recommendations.