B2659 Code - Courtesy Switch Fault
Quick Answer
For vehicles equipped with Keyless Entry System (RKE), the vehicle security module sends an interior lamps ON request to the Instrument Cluster Module (ICM) through UART Based Protocol (UBP) whenever a door has been opened, the unlock button has been pressed on the remote transmitter, or when an unlock request has been entered with the keyless keypad (if equipped). Common causes include Blown Courtesy Lamp Bulb, Faulty Door Ajar Switch, Faulty Interior Lamp Switch. 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
- B2659 indicates Courtesy Switch Fault.
- Common causes
- Common causes include Blown Courtesy Lamp Bulb, Faulty Door Ajar Switch, Faulty Interior Lamp Switch.
- 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 B2659 Description
For non-RKE vehicles, the ICM energizes the circuit when a door has been opened, which provides power to the interior lamps. The interior lamps can also be turned ON or OFF with the interior lamp switch. The interior lamps are grounded through the circuit, and will remain illuminated until the ICM removes voltage from the circuit.
What are the Possible Causes of the DTC B2659?
- Blown Courtesy Lamp Bulb
- Faulty Door Ajar Switch
- Faulty Interior Lamp Switch
- Interior Lamp Switch harness is open or shorted
- Interior Lamp Switch circuit poor electrical connection
- Faulty Instrument Cluster Module (ICM)
How to Fix the DTC B2659?
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 B2659 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
- B2659 Ford — Courtesy Switch Fault
- B2659 Lincoln — Courtesy Switch Fault
- B2659 Mercury — Courtesy Switch Fault
Frequently Asked Questions about B2659 Code
1. What does the OBDII code B2659 mean?
Code B2659 indicates a "Courtesy Switch Fault," which typically refers to a malfunction in the courtesy light circuit or associated switch.
2. What are the symptoms of a B2659 code?
Common symptoms include the courtesy lights not turning on or off properly, lights staying on continuously, or failure to illuminate when doors are opened.
3. What causes the B2659 code?
This code can be caused by a faulty courtesy light switch, damaged wiring, a blown fuse, or a problem with the body control module (BCM).
4. How can I diagnose the B2659 code?
Start by inspecting the courtesy light switch, wiring, and connectors for damage or corrosion. Check the fuse for the courtesy light circuit and scan for additional codes.
5. Can a blown fuse trigger the B2659 code?
Yes, a blown fuse in the courtesy light circuit can disrupt the electrical flow, leading to a B2659 fault code.
6. How do I fix the B2659 code?
Repair or replace the faulty courtesy light switch, fix damaged wiring, replace a blown fuse, or reprogram/replace the body control module if necessary.
7. Is the B2659 code serious?
It is not critical for vehicle performance but can cause inconvenience, such as lights staying on and draining the battery.
8. Can I drive with the B2659 code?
Yes, you can drive with this code, but you should address it promptly to avoid battery drainage or further electrical issues.
9. How much does it cost to repair a B2659 code?
The repair cost can vary depending on the issue, from $50 for a new switch to over $200 if a BCM replacement or reprogramming is required.
10. Can I reset the B2659 code without fixing the issue?
Clearing the code without addressing the root cause will likely result in the code returning, as the fault persists.
Discuss the causes and fixes for B2659 OBDII Code
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