Passenger Seat Rear Switch Circuit High Voltage
The seat control module (SCM) or body control module (BCM) has detected an unexpected high voltage (short to battery) on the signal circuit of the passenger seat rear travel switch. This indicates that the signal wire is contacting a constant or switched 12V power source, preventing the module from reading the switch position correctly.
1. Commonly Affected Makes
2. Most Common Causes
- Signal circuit wiring shorted to B+ (positive battery voltage)
- Defective passenger seat adjuster switch (internal short to battery)
- Damaged seat control module (SCM/DSM)
- Corroded connectors or bent terminals bridging power and signal circuits
3. Symptoms You Will Notice
- Passenger seat rearward movement inoperative or erratic
- Seat position memory not working or incorrect
4. Step-by-Step Diagnosis
Check for technical service bulletins (TSBs) related to seat wiring or module issues.
Visually inspect the passenger seat wiring harness and connectors for damage, corrosion, or bent pins.
Disconnect the seat adjuster switch and measure voltage on the signal wire; it should be near 0V with the switch open. If battery voltage is present, trace and repair the short to B+.
Test the switch by measuring resistance between terminals; replace if shorted internally.
If wiring and switch are OK, suspect a faulty SCM/DSM and perform module self-test or replacement.
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, the vehicle is generally safe to drive, but the passenger seat may not adjust properly, which could be a comfort or convenience issue.
How much does it cost to fix?▼
Repair costs range from $100 to $400 depending on the cause: a wiring repair may cost $100-$200, a switch replacement $50-$150, and a seat control module replacement $200-$400 plus labor.