Yes, there are several potential reasons why the parking brake light on your 2009 Chevy Express 3500 V8 stays on constantly. Here are some steps you can take to diagnose and potentially fix the issue:

1. **Check the Parking Brake**:
- Ensure that the parking brake is fully released. Sometimes the handle or pedal might not fully disengage, causing the light to remain on.
- Check the parking brake mechanism for any signs of damage or sticking parts.

2. **Inspect the Brake Fluid Level**:
- A low brake fluid level in the master cylinder reservoir can trigger the parking brake light. Locate the brake fluid reservoir under the hood and check the fluid level. If it’s low, add the appropriate type of brake fluid to reach the recommended level.
- Check for any leaks around the master cylinder, brake lines, or at the brake calipers/wheel cylinders that might be causing the fluid loss.

3. **Brake Fluid Sensor**:
- The parking brake light can also be activated by a faulty brake fluid level sensor. If the fluid levels are correct and the light remains on, the sensor itself might need to be inspected or replaced.

4. **Parking Brake Switch**:
- The parking brake system usually has a switch that detects whether the brake is engaged or not. This switch can become faulty or misaligned. Locate the switch (often found near the parking brake pedal or handle) and inspect it for proper operation. It might need adjustment or replacement.

5. **Electrical Issues**:
- Inspect the wiring and connections related to the parking brake system. Look for frayed wires, loose connections, or corrosion that might be causing an electrical short or open circuit.

6. **ABS (Anti-lock Braking System) Issues**:
- Sometimes, an ABS problem can also trigger the parking brake light. Use an OBD-II scanner to check for any error codes related to the ABS system. If any codes are present, further diagnosis may be needed to resolve these issues.

7. **Dashboard Light Circuit**:
- It’s possible that the issue lies within the dashboard circuit itself. If all other components are working correctly and the light still stays on, there might be a short or issue within the instrument cluster.

Here’s a step-by-step troubleshooting outline:
- Fully disengage the parking brake and check the light.
- Check brake fluid levels and top off if necessary.
- Inspect the brake fluid sensor and replace if necessary.
- Examine the parking brake switch and its alignment.
- Inspect associated wiring for any damage.
- Use an OBD-II scanner to detect any code linked to the braking system.
- If everything else checks out, consider inspecting the instrument cluster.

If, after following these steps, the issue persists, it might indicate a more complex problem with the vehicle's braking or electrical systems. In such cases, getting a detailed diagnosis from a brake specialist or professional mechanic is usually the best course of action.