Camshaft Position Actuator Solenoid Test (2002-2009 4.2L Chevrolet TrailBlazer, GMC Envoy)

TEST 2: Making Sure That The Solenoid Is Getting Power

If you find that the solenoid's spool valve moves when you apply battery power and Ground to it, then the next step is to make sure that the fuel injection computer is supplying it with power.

Power is in the form of 12 Volts and is provided by the brown (BRN) wire of the camshaft position actuator solenoid's electrical connector.

IMPORTANT: Be careful not to damage the female terminal of the solenoid's electrical connector with your multimeter test lead. Use the appropriate tool to connect your multimeter test lead to the terminal or wire.

These are the test steps:

1. 1

   Disconnect the camshaft position actuator solenoid from its electrical connector.

2. 2

   Place your multimeter in Volts DC mode.

3. 3

   Connect the red multimeter test lead to the brown (BRN) wire of the camshaft position actuator solenoid's electrical connector.

4. 4

   Connect the black multimeter test lead to the battery negative (-) terminal.

5. 5

   Turn the key ON but don't crank or start the engine.

6. 6

   You should see a reading of 10 to 12 Volts DC.

Let's examine your test results:

CASE 1: 10 to 12 Volts present. This is the correct and expected test result and lets you know that the camshaft position actuator solenoid is being supplied with power from your TrailBlazer or Envoy's fuel injection computer.

For more suggestions on troubleshooting the camshaft position actuator trouble code see: The Camshaft Position Actuator Solenoid Trouble Code Does Not Go Away.

CASE 2: 10 to 12 Volts ARE NOT present. Without power the camshaft position actuator solenoid will not work.

The most likely cause of this missing voltage is an open-circuit problem in the wire between the solenoid's connector and the PCM's connector.

The Camshaft Position Actuator Solenoid Trouble Code Does Not Go Away

The most common failure you'll encounter with the camshaft position actuator solenoid is that its internal spool valve does not move anymore. And as you learned in the previous page, testing this particular condition isn't difficult.

There are also quite a few other things can cause the computer on your 4.2L Chevrolet TrailBlazer or GMC Envoy to think that the camshaft position actuator solenoid is defective when it isn't.

Some of the things that can cause this to happen are:

• The engine does not have enough oil.
• The engine oil pump is not supplying enough oil pressure.
• The wrong grade of oil was used.
• Defective or damaged camshaft position sensor.
• The timing chain has too much slack. Either because it has streteched or one of its tensioners is worn out.
• The copper wire inside the wire's insulation has broken right before it enters the solenoid's electrical connector.
• The two wires have shorted together at the point right before they enter the electrical connector. This is usually due to the wires insulation peeling off and exposing the copper wires.

More GM 4.2L Test Tutorials

I've written quite a few tutorials for the 4.2L Chevrolet TrailBlazer And GMC Envoy. You can find them here: GM 4.2L Index Of Articles.

Here's a sample of the tutorials you'll find there:

• How To Test For A Blown Head Gasket (2002-2009 4.2L Chevrolet TrailBlazer).
• How To Test The MAP Sensor (2002-2007 4.2L Chevrolet Trailblazer).
• How Often Should I Replace The Spark Plugs? (2002-2009 4.2L Chevrolet TrailBlazer).
• How To Test Engine Compression (2002-2009 4.2L Chevrolet TrailBlazer).
• Electronic Throttle Body Tests (2002-2007 4.2L Chevrolet TrailBlazer).