B3820 Code - Left Rear Window Down Control Circuit
Quick Answer
The Body Control Module (BCM) grounds the control side of the left rear power window down relay upon receiving a class 2 message from the Driver Door Module (DDM). Common causes include Faulty Left Rear Power Window Switch, Left Rear Power Window Switch harness is open or shorted, Left Rear Power Window Switch circuit poor electrical connection. 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
- B3820 indicates Left Rear Window Down Control Circuit.
- Common causes
- Common causes include Faulty Left Rear Power Window Switch, Left Rear Power Window Switch harness is open or shorted, Left Rear Power Window Switch circuit poor electrical connection.
- 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.
Code B3820 Description
What are the Possible Causes of the DTC B3820?
- Faulty Left Rear Power Window Switch
- Left Rear Power Window Switch harness is open or shorted
- Left Rear Power Window Switch circuit poor electrical connection
- Faulty Body Control Module (BCM)
How to Fix the DTC B3820?
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 B3820 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 B3820 code?
Need more information on how to fix the B3820 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the B3820 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- B3820 Buick — Left Rear Window Down Control Circuit
- B3820 Cadillac — Left Rear Window Down Control Circuit
- B3820 Chevrolet — Left Rear Window Down Control Circuit
- B3820 GMC — Left Rear Window Down Control Circuit
Frequently Asked Questions about B3820 Code
1. What are common symptoms of OBDII code B3820 (Left Rear Window Down Control Circuit)?
- Common symptoms include the left rear window being stuck in the down position, the window not responding to the control switch, or the window moving intermittently.
2. What can cause OBDII code B3820 to trigger?
- The code B3820 can be triggered by issues such as a faulty window motor, damaged wiring or connectors in the left rear window circuit, or a malfunctioning control module.
3. How can I diagnose the cause of OBDII code B3820?
- To diagnose OBDII code B3820, you can perform a visual inspection of the wiring and connectors in the left rear window circuit, test the window motor for proper function, and use a scan tool to read live data and confirm the issue.
4. What is the typical repair process for OBDII code B3820?
- The typical repair process for code B3820 involves repairing or replacing any damaged wiring or connectors, testing and potentially replacing the window motor, and resetting the control module to clear the code.
5. Are there any quick tips for troubleshooting OBDII code B3820 at home?
- Quick tips for troubleshooting code B3820 at home include checking the fuse related to the left rear window, ensuring the window switch is functioning correctly, and listening for any unusual noises coming from the door panel.
6. Can OBDII code B3820 be safely ignored?
- Ignoring OBDII code B3820 may result in the left rear window being stuck in the down position, posing a security risk and potential safety hazard. It is recommended to address the issue promptly to ensure proper functionality.
7. Is it possible to reset OBDII code B3820 without making repairs?
- While clearing the code temporarily may be possible by disconnecting the battery or using a scan tool, the underlying issue causing code B3820 will persist until properly diagnosed and repaired.
8. How much does it typically cost to repair OBDII code B3820?
- The cost to repair OBDII code B3820 can vary depending on the specific cause of the issue, but it may involve expenses for parts such as a window motor, wiring repairs, and labor costs for diagnosis and repair.
9. Can extreme weather conditions contribute to triggering OBDII code B3820?
- Extreme weather conditions such as excessive heat, cold, or humidity can potentially exacerbate existing issues in the left rear window control circuit, leading to the triggering of OBDII code B3820.
10. Are there any preventative maintenance tips to avoid encountering OBDII code B3820 in the future?
- Regularly inspecting and maintaining the condition of the window components, wiring, and control module can help prevent issues that may trigger OBDII code B3820. Additionally, avoiding excessive force when operating the window can help prolong its lifespan.
Discuss the causes and fixes for B3820 OBDII Code
Code B3820 comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
