How To Test The Headlight Switch (1994-1997 2.2L Chevy S10)

TEST 2: Bypassing The Headlight Switch

In this test section, we're gonna' use a jumper wire to bypass the headlight and park-lights switches.

For the park-lights, we're gonna' jumper the wires labeled A and E of the headlight switch connector (see photo above).

For the headlights, we're gonna' jumper the wires labeled C and D of the headlight switch connector (see photo above).

If all is OK, you should see the park-lamps or the headlights turning on when the indicated wires are jumpered together.

OK, these are the test steps:

1. 1

   Disconnect and remove the headlight switch.

2. 2

   Check that wires C and E have battery power.
   
   If battery power is NOT present, stop here and find out why power is missing and restore it before continuing to the next steps.

3. 3

   Jumper wires A and E of the headlight switch connector.
   
   Your Chevy S10 or GMC Sonoma's park-lights should come on.

4. 4

   Jumper wires C and D of the headlight switch connector.
   
   Your Chevy S10 or GMC Sonoma's headlights should come on.

Let's take a look at your test results:

CASE 1: The park-lamps and headlights turned on when the indicated wires were jumpered together and the headlight switch passed TEST 1. This is the correct test result and you can conclude that the headlight switch is defective.

CASE 2: The park-lamps or the headlights DID NOT turn on when the indicated wires were jumpered together but the headlight switch passed TEST 1. This test result usually points to a problem in the wiring between the headlight switch connector and the headlights/park-lamps.

CASE 3: The park-lamps or the headlights DID NOT turn on when the indicated wires were jumpered together and the headlight switch DID NOT pass TEST 1. This test result usually points to a problem in the wiring between the headlight switch and/or the headlights/park-lamps and a bad headlight switch.

More 2.2L GM Tutorials

You can find a complete list of 2.2L Chevy S10 (GMC Sonoma) tutorials in this index:

• GM 2.2L Index Of Articles.

Here's a small sample of the tutorials you'll find in the index:

• How To Test The Throttle Position Sensor (1998-2003 2.2L S10 and Sonoma).
• How To Test The Throttle Position Sensor (1995-1997 2.2L S10 and Sonoma).
• Oxygen Sensor Heater Test -P0141 (2.2L Chevy S10 - GMC Sonoma).
• How To Test the MAP Sensor (GM 2.2L) (at troubleshootmyvehicle.com).