* Faulty Seat Switch: The most common culprit. A malfunctioning switch can send a constant signal to the heating element, even when the switch is in the "off" position. This is often caused by a short circuit or a worn-out component within the switch itself.
* Wiring Issue: A short circuit or frayed wiring in the harness leading to the seat heater can also cause it to turn on unintentionally. This could be anywhere between the switch and the heating element. Moisture intrusion is a common cause of wiring problems.
* Faulty Heating Element: While less likely to cause *automatic* activation, a short in the heating element itself *could* potentially trigger the system to believe it's on, even when it's not.
* Body Control Module (BCM) Problem: The BCM is the brain of many electrical systems in your vehicle. A malfunctioning BCM could send incorrect signals to the heated seat system, causing it to turn on unexpectedly. This is less likely, but possible.
* Aftermarket Modifications: If you've had any aftermarket modifications done to your electrical system, they could be interfering with the heated seat circuitry.
What to do:
1. Check the Switches: Carefully examine the switches for any signs of damage, melting, or unusual wear. Try toggling them several times.
2. Inspect Wiring (if comfortable): If you're comfortable working with car wiring, visually inspect the wiring harness leading to the heated seats for any signs of damage, fraying, or corrosion. This requires some mechanical skill and caution to avoid causing further damage.
3. Have it Professionally Diagnosed: The best approach is to take your Tahoe to a qualified mechanic or an auto electrician. They have the tools and expertise to properly diagnose the problem and determine whether it's a faulty switch, wiring, heating element, or BCM issue. They can also safely access and repair the system.
Ignoring the problem could lead to further damage, potential fire hazards (due to short circuits), or even draining your battery. Getting it professionally diagnosed and repaired is recommended.
