Cruise Control System: Overview Chevrolet TrailBlazer I

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Description

The Cruise Control Diagnostic System Check is an organized approach to identifying a condition created by an electronic control system failure. The Diagnostic System Check directs the service technician to the next logical step in diagnosing the concern.

Understanding the system, the table, and using it correctly reduces diagnostic time and prevents misdiagnosis. For a review of the cruise control system, refer to CRUISE CONTROL DESCRIPTION AND OPERATION (4.2L) or CRUISE CONTROL DESCRIPTION AND OPERATION (5.3L) .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 2. Lack of communication may be due to a malfunction in the class 2 serial data circuit. The specified procedure will determine the particular condition.
2. 5. The presence of DTCs which begin with "U" indicates that some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

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The numbers below refer to the step numbers on the diagnostic table.

1. 2. This step determines if condition is present.
2. 3. This step determines if the switch is at fault.

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The numbers below refer to the step numbers on the diagnostic table.

1. 3. This step determines if condition is present.

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The number below refers to the step number on the diagnostic table.

1. 2. This step determines if condition is present.

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The number below refers to the step number on the diagnostic table.

1. 3. This step determines if condition is present.

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The numbers below refer to the step numbers on the diagnostic table.

1. 8. This step tests the cruise control set/coast switch signal circuit for an open or for a high resistance.
2. 9. This step tests the cruise control resume/accel switch signal circuit for an open or for a high resistance.
3. 10. This step tests the ignition 3 voltage circuit for an open, for a short to ground or for a high resistance.
4. 28. DTCs will set in the PCM when you perform this table.

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Cruise Control Description and Operation (4.2L)

Cruise control is a speed control system that maintains a desired vehicle speed under normal driving conditions at vehicle speeds above 40 km/h (25 mph). Steep grades may cause variations in the selected vehicle speeds.

The following are the main components of the cruise control system

1. The powertrain control module (PCM)
2. The On/Off switch
3. The Resume/Accel switch
4. The Set/Coast switch
5. The TCC brake switch
6. The stop lamp switch
7. The throttle actuator control (TAC) motor
8. The vehicle speed sensor

Cruise Control Description and Operation (5.3L)

Cruise control is a speed control system that maintains a desired vehicle speed under normal driving conditions at vehicle speeds above 40 km/h (25 mph). Steep grades may cause variations in the selected vehicle speeds.

The following are the main components of the cruise control system

1. The powertrain control module (PCM)
2. The On/Off switch
3. The Resume/Accel switch
4. The Set/Coast switch
5. The TCC/brake switch
6. The stop lamp switch
7. The throttle actuator control (TAC) module
8. The vehicle speed sensor