AutoCodes – Generic – B1846

B1846 Code - Ignition Tamper Circuit Open

Quick Answer

The Body Control Module (BCM) monitors the Ignition Switch. Common causes include Faulty Ignition Switch, Ignition Switch harness is open or shorted, Ignition 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: B1846 indicates Ignition Tamper Circuit Open.
Common causes: Common causes include Faulty Ignition Switch, Ignition Switch harness is open or shorted, Ignition 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 5,017

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 Jul 02, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1846 Description

The Body Control Module (BCM) monitors the Ignition Switch. The BCM sets the OBDII code when the Ignition Switch is not to factory specifications.

OBDII Code B1846 - Ignition Tamper Circuit Open - AutoCodes.com — B1846 Code - Ignition Tamper Circuit Open

What does this mean?

What are the Possible Causes of the DTC B1846?

Faulty Ignition Switch
Ignition Switch harness is open or shorted
Ignition Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B1846?

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 B1846 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 B1846 code?

Need more information on how to fix the B1846 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1846 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B1846 Lexus — Open In Curtain Shield Squib Left 2nd Step Circuit
B1846 Scion — Open In Curtain Shield Squib Left 2nd Step Circuit
B1846 Toyota — Open In Curtain Shield Squib Left 2nd Step Circuit

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 B1846 Code

1. What are some common symptoms of OBDII code B1846 (Ignition Tamper Circuit Open)?

- Common symptoms include difficulty starting the vehicle, intermittent stalling, and the ignition system not functioning properly.

2. What can cause the OBDII code B1846 (Ignition Tamper Circuit Open) to trigger?

- The code may be triggered by a loose or damaged wiring connection in the ignition tamper circuit, a faulty ignition tamper module, or issues with the ignition switch.

3. How can I diagnose the cause of OBDII code B1846 (Ignition Tamper Circuit Open)?

- To diagnose the issue, you can use a diagnostic scanner to retrieve the specific trouble code and then inspect the wiring, connectors, and components related to the ignition tamper circuit.

4. What are some repair tips for fixing OBDII code B1846 (Ignition Tamper Circuit Open)?

- Repair tips include checking and repairing any loose or damaged wiring connections, replacing the ignition tamper module if necessary, and ensuring the ignition switch is functioning correctly.

5. Can OBDII code B1846 (Ignition Tamper Circuit Open) be fixed by resetting the vehicle's computer?

- Resetting the vehicle's computer may temporarily clear the code, but if the underlying issue causing the code to trigger is not addressed, the code is likely to return.

6. Is it safe to continue driving with OBDII code B1846 (Ignition Tamper Circuit Open) present?

- It is not recommended to continue driving with this code present, as it can lead to potential starting and ignition system issues that may affect the vehicle's performance and safety.

7. How much does it typically cost to repair OBDII code B1846 (Ignition Tamper Circuit Open)?

- The cost of repairing this code can vary depending on the underlying cause and the specific components that need to be replaced, but it may range from $100 to $300 or more.

8. Can I fix OBDII code B1846 (Ignition Tamper Circuit Open) myself, or should I take it to a mechanic?

- If you have experience with automotive electrical systems and diagnostics, you may be able to address the issue yourself. Otherwise, it is recommended to take your vehicle to a qualified mechanic for proper diagnosis and repair.

9. Will OBDII code B1846 (Ignition Tamper Circuit Open) cause my vehicle to fail an emissions test?

- Yes, this code can cause your vehicle to fail an emissions test, as it indicates a malfunction in the ignition tamper circuit that can impact the vehicle's emissions control system.

10. How long does it typically take to repair OBDII code B1846 (Ignition Tamper Circuit Open)?

- The repair time can vary depending on the complexity of the issue and the availability of parts, but it may take anywhere from 1 to 3 hours to diagnose and fix the problem.