AutoCodes – Buick – B1970 Buick

B1970 Buick Code - Exterior Ligth Power Fault

Quick Answer

The Body Control Module (BCM) commands exterior lights on by energizing Low Beam and Parking Light Relays. Common causes include Faulty Low Beam and Parking Light Relay, Low Beam and Parking Light Relay harness is open or shorted, Low Beam and Parking Light Relay 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: B1970 Buick indicates Exterior Ligth Power Fault.
Common causes: Common causes include Faulty Low Beam and Parking Light Relay, Low Beam and Parking Light Relay harness is open or shorted, Low Beam and Parking Light Relay 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.

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Code Popularity 556

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 Aug 01, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1970 Buick Description

The Body Control Module (BCM) commands exterior lights on by energizing Low Beam and Parking Light Relays. The Diagnostic Trouble Code (DTC) B1970 will set when exterior lights have been commanded on and BCM detects low voltage (short to ground) in the wire between BCM and relays. When DTC B1970 is set, BCM will command exterior lights off, and then attempt to turn exterior lights on until lights are no longer requested. DTC B1970 will clear when conditions for fault no longer exist or when scan tool is used. A history DTC will clear after 50 consecutive ignition cycles if conditions for fault no longer exist.

OBDII Code B1970 Buick - Exterior Ligth Power Fault - AutoCodes.com — B1970 Buick Code - Exterior Ligth Power Fault

What does this mean?

What are the Possible Causes of the DTC B1970 Buick?

Faulty Low Beam and Parking Light Relay
Low Beam and Parking Light Relay harness is open or shorted
Low Beam and Parking Light Relay circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B1970 Buick?

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 B1970 Buick 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.

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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 B1970 Buick Code

1. What are common symptoms of OBDII code B1970 in a Buick related to an Exterior Light Power Fault?

- Common symptoms include non-functioning exterior lights such as headlights, taillights, or turn signals, and potential dashboard warning lights related to exterior lighting issues.

2. What are the possible causes of OBDII code B1970 in a Buick indicating an Exterior Light Power Fault?

- The code may be triggered by a faulty exterior light switch, a wiring issue in the lighting system, a blown fuse, or a malfunctioning lighting control module.

3. How can I troubleshoot OBDII code B1970 in my Buick for an Exterior Light Power Fault?

- Start by checking the exterior light bulbs, fuses, and the wiring harness for any visible damage or corrosion. Test the light switch and lighting control module for proper functionality.

4. Can a DIY enthusiast repair OBDII code B1970 related to an Exterior Light Power Fault in a Buick?

- Depending on the specific cause, DIY repairs may be possible, such as replacing a blown fuse or a faulty light bulb. However, more complex issues like wiring problems may require professional assistance.

5. Is it safe to drive my Buick with OBDII code B1970 related to an Exterior Light Power Fault illuminated?

- It is not recommended to drive the vehicle with exterior lights not functioning properly, as it can compromise safety, reduce visibility, and potentially lead to accidents.

6. How much does it typically cost to repair OBDII code B1970 in a Buick due to an Exterior Light Power Fault?

- The cost of repair can vary depending on the specific cause of the issue. Simple fixes like replacing a light bulb may be inexpensive, while more complex repairs involving wiring or control modules can be more costly.

7. Can resetting the OBDII system clear the B1970 code related to an Exterior Light Power Fault in a Buick?

- Resetting the OBDII system may temporarily clear the code, but if the underlying issue causing the Exterior Light Power Fault is not addressed, the code is likely to reappear.

8. Are there any preventive maintenance tips to avoid triggering OBDII code B1970 in a Buick for an Exterior Light Power Fault?

- Regularly inspecting the exterior lights for proper functioning, keeping the wiring harness clean and free of corrosion, and promptly addressing any lighting issues can help prevent this fault code.

9. Will OBDII code B1970 in a Buick related to an Exterior Light Power Fault affect the vehicle's overall performance?

- While the code itself may not directly impact the performance of the vehicle, the underlying lighting issue can compromise safety and visibility, making it important to address promptly.

10. Can extreme weather conditions contribute to triggering OBDII code B1970 in a Buick for an Exterior Light Power Fault?

- Yes, extreme weather conditions like heavy rain, snow, or temperature fluctuations can potentially damage the exterior lighting components or wiring, leading to the fault code. Regular maintenance and inspection can help mitigate these risks.