B2124: Seat/Mirror Memory Reset Switch Circuit Low
The passenger door module (PDM) or body control module (BCM) has detected a continuous low voltage signal on the seat/mirror memory reset switch circuit. This indicates the switch is stuck in the activated position (closed) or there is a short to ground in the signal wiring, preventing the memory system from operating normally.
1. Commonly Affected Makes
2. Most Common Causes
- Memory reset switch stuck closed or internally damaged
- Short to ground in the switch signal circuit
- Corroded or damaged terminals in the PDM connector
- Internal failure of the passenger door module (PDM)
3. Symptoms You Will Notice
- Seat and mirror memory settings not saving or recalling
- Memory reset function inoperative or constantly active
4. Step-by-Step Diagnosis
Scan for additional codes and verify B2124 is current
Inspect the memory reset switch for mechanical sticking or damage
Check the switch signal circuit for short to ground using a multimeter
Examine the PDM connector for corrosion, bent or broken pins
If all else is normal, suspect a faulty PDM and perform module testing
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, the vehicle is generally safe to drive, but the memory functions for the seat and mirrors will not work properly. Have it diagnosed soon to avoid further electrical issues.
How much does it cost to fix?▼
Depending on the cause, repair costs typically range from $100 to $400. A simple switch replacement may be under $150, while a PDM replacement could be $300–$400 including labor.