AutoCodes – Generic – B1391

B1391 Code - Oil Level Switch Circuit Failure

Quick Answer

The Powertrain Control Module (PCM) monitors the Oil Level Switch. Common causes include Faulty Oil Level Switch, Oil Level Switch harness is open or shorted, Oil Level 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: B1391 indicates Oil Level Switch Circuit Failure.
Common causes: Common causes include Faulty Oil Level Switch, Oil Level Switch harness is open or shorted, Oil Level 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.

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Code Popularity 4,945

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 20, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1391 Description

The Powertrain Control Module (PCM) monitors the Oil Level Switch. The PCM sets the OBDII code when the Oil Level Switch is not to factory specifications.

OBDII Code B1391 - Oil Level Switch Circuit Failure - AutoCodes.com — B1391 Code - Oil Level Switch Circuit Failure

What does this mean?

What are the Possible Causes of the DTC B1391?

Faulty Oil Level Switch
Oil Level Switch harness is open or shorted
Oil Level Switch circuit poor electrical connection
Faulty Powertrain Control Module (PCM)

How to Fix the DTC B1391?

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 B1391 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 B1391 code?

Need more information on how to fix the B1391 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1391 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B1391 Hyundai — Passenger Seat Track Position Sensor Short Or Short To Battery
B1391 KIA — Passenger Seat Track Position Sensor Short Or Short To Battery

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 B1391 Code

1. What are the common symptoms of OBDII code B1391 (Oil Level Switch Circuit Failure)?

- Common symptoms include an illuminated oil pressure warning light on the dashboard, inaccurate oil level readings, or no oil level reading at all.

2. What are some possible causes of OBDII code B1391?

- The code B1391 can be triggered by a faulty oil level switch, damaged wiring or connectors in the oil level switch circuit, or low engine oil level.

3. How can I diagnose the cause of OBDII code B1391?

- To diagnose the issue, you can start by visually inspecting the oil level switch and its wiring for any signs of damage. You can also use a multimeter to test the continuity of the circuit.

4. Can driving with OBDII code B1391 cause any serious damage to my vehicle?

- Driving with code B1391 may lead to inaccurate oil level readings, which can potentially cause engine damage due to insufficient lubrication. It is recommended to address the issue promptly.

5. What are some repair tips for fixing OBDII code B1391?

- Repair options include replacing the faulty oil level switch, repairing damaged wiring or connectors, and ensuring the engine oil level is at the appropriate level. Clearing the code with an OBDII scanner is also recommended after repairs.

6. Is it safe to continue driving my vehicle with OBDII code B1391 unresolved?

- It is not recommended to drive the vehicle with code B1391 unresolved, as it can lead to potential engine damage or inaccurate oil level readings. It's best to address the issue as soon as possible.

7. How much does it typically cost to repair OBDII code B1391?

- The cost of repairing code B1391 can vary depending on the cause of the issue and the labor rates of the repair shop. In general, the cost may range from $100 to $300, including parts and labor.

8. Can I reset OBDII code B1391 without fixing the underlying issue?

- While you can clear the code temporarily with an OBDII scanner, it is important to address the root cause of the issue to prevent further problems with the oil level monitoring system.

9. Are there any preventive maintenance steps to avoid OBDII code B1391 in the future?

- Regularly checking and maintaining the engine oil level, as well as inspecting the oil level switch and its wiring during routine maintenance, can help prevent issues that trigger code B1391.

10. How long does it typically take to repair OBDII code B1391?

- The repair time for code B1391 can vary based on the specific cause of the issue and the expertise of the technician. In general, it may take 1-2 hours to diagnose and repair the problem.