Output Control

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Output Control
WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Backup Lamps

The scan tool displays the commanded state of the BCM which directly supplies battery positive voltage to the backup lamps. The scan tool displays On when the BCM activates the backup lamps upon receiving a backup lamp request signal from the backup lamp switch.

Dimming Level

The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the interior lighting circuits. The scan tool displays 0 percent when the interior lamps illumination is OFF. The scan tool displays 100 percent when the interior lamp illumination is at full intensity.

High Beams

The scan tool displays the commanded state of the high beam relay. The scan tool displays On when the BCM allows the high beam relay to go to ground activating the high beam headlamps.

Inadvertent Power Relay

The scan tool displays the state of the inadvertent power battery rundown protection feature of the BCM. The scan tool displays Off when all inadvertent power circuits are functioning normally.

Low Beam Duty Cycle

The scan tool displays the commanded state of the headlamp driver module. The BCM displays 100 percent for the low beam headlamps in low beam headlamp mode at full intensity or 81 percent in the DRL mode resulting with a reduced intensity.

Park Lamp Relay

The scan tool displays the commanded state of the park lamp relay. The scan tool displays On when the BCM allows the park lamp relay to go to ground to activate the park lamps.

RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.