GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Astro - 2WD 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Daytime Running Lights (DRL) System Check

DRL Diagnostic System Check

Step

Action

Normal Result(s)

Abnormal Result(s)*

1
  1. Turn the headlamp switch to the ON position (headlamps on).
  2. Turn the headlamp dimmer switch to the LOW beam position.
  1. The low beam headlamps are ON.
  2. The high beam headlamps are OFF.
    • Headlamps Inoperative-Low Beam .
    • Headlamps Inoperative-Low and High Beams.
    • Headlamp Inoperative-One Lamp.

2
  1. Turn the headlamp dimmer switch to the HIGH beam position.
  2. Return the headlamp dimmer switch to the LOW beam position.
  1. The high beam headlamps are ON.
  2. The high beam indicator is ON.
  3. The low beam headlamps are OFF.
  4. Headlamps return to the low beam position.
    • Headlamps Inoperative-High Beams (and/or High Beam Indicator).
    • Headlamps Inoperative-Low and High Beams.
    • Headlamp Inoperative-One Lamp.

3
    • Turn the headlamp switch to the OFF position.
    • Turn the ignition switch to the ON position.

Front turn signal lamps illuminate for daytime running lamps (Domestic/Export).

DRL Headlamps Inoperative (Domestic/Export).

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.