B1840 Code - Driver Seat Lumbar Up Switch Circuit
Quick Answer
The Seat Memory Control Module supplies a reference voltage to each signal circuit of the Driver Seat Adjuster Switch. Common causes include Faulty Driver Seat Adjuster Switch, Driver Seat Adjuster Switch harness is open or shorted, Driver Seat Adjuster 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
- B1840 indicates Driver Seat Lumbar Up Switch Circuit.
- Common causes
- Common causes include Faulty Driver Seat Adjuster Switch, Driver Seat Adjuster Switch harness is open or shorted, Driver Seat Adjuster 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 B1840 Description
What are the Possible Causes of the DTC B1840?
- Faulty Driver Seat Adjuster Switch
- Driver Seat Adjuster Switch harness is open or shorted
- Driver Seat Adjuster Switch circuit poor electrical connection
- Faulty Seat Memory Control Module
How to Fix the DTC B1840?
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 B1840 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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Information for Specific Makes
- B1840 Buick — Driver Seat Lumbar Up Switch Circuit
- B1840 Cadillac — Driver Seat Lumbar Up Switch Circuit
- B1840 Chevrolet — Driver Seat Lumbar Up Switch Circuit
- B1840 GMC — Driver Seat Lumbar Up Switch Circuit
- B1840 Lexus — Short In Curtain Shield Squib Right 2nd Step Circuit
- B1840 Scion — Short In Curtain Shield Squib Right 2nd Step Circuit
- B1840 Toyota — Short In Curtain Shield Squib Right 2nd Step Circuit
Frequently Asked Questions about B1840 Code
1. What are the common symptoms of OBDII code B1840 (Driver Seat Lumbar Up Switch Circuit)?
The common symptoms include the driver seat lumbar up switch not functioning properly, the lumbar support not adjusting correctly, or the seat lumbar support being stuck in one position.
2. What can cause OBDII code B1840 to trigger?
The code B1840 can be triggered by a faulty driver seat lumbar up switch, damaged wiring or connectors in the circuit, or a malfunction in the seat control module.
3. How can I diagnose the cause of OBDII code B1840?
You can diagnose the cause of B1840 by inspecting the driver seat lumbar up switch for physical damage, checking the wiring and connectors for any signs of wear or corrosion, and using a scan tool to read the trouble codes stored in the seat control module.
4. Can I repair OBDII code B1840 on my own?
If you have experience with automotive electrical systems and access to the necessary tools, you may be able to repair B1840 on your own by replacing the faulty lumbar up switch, repairing damaged wiring or connectors, or resetting the seat control module.
5. Is it safe to continue driving with OBDII code B1840 active?
While the vehicle may still be operable with code B1840 present, it is recommended to address the issue promptly to avoid potential discomfort or inconvenience caused by the malfunctioning driver seat lumbar up switch.
6. Are there any temporary fixes for OBDII code B1840?
Temporary fixes such as resetting the seat control module or manually adjusting the lumbar support position may provide a temporary solution, but it is advisable to properly diagnose and repair the underlying issue to prevent further problems.
7. How much does it typically cost to repair OBDII code B1840?
The cost of repairing B1840 can vary depending on the root cause of the issue, labor rates in your area, and the cost of replacement parts. It is recommended to obtain quotes from local mechanics or repair shops for an accurate estimate.
8. Can OBDII code B1840 affect other functions of the driver seat?
While code B1840 specifically relates to the driver seat lumbar up switch circuit, electrical issues in the seat control module or related components may potentially impact other functions of the driver seat, such as reclining or adjusting the seat position.
9. Will resetting the OBDII code B1840 clear the issue permanently?
Resetting the code may temporarily clear the fault code, but if the underlying issue with the driver seat lumbar up switch circuit is not resolved, the code is likely to reappear. It is important to diagnose and address the root cause of the problem.
10. How can I prevent OBDII code B1840 from recurring in the future?
To prevent OBDII code B1840 from recurring, it is essential to ensure that the driver seat lumbar up switch is in good working condition, regularly inspect the wiring and connectors for any damage, and address any electrical issues promptly to maintain the functionality of the seat lumbar support system.
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