GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The cruise control module uses the cruise engaged circuit to request cruise control. If improper conditions are present, the PCM will disable cruise control via the cruise inhibit control circuit. During cruise control, if the PCM detects a vehicle speed greater than the calibrated value, the PCM will inhibit the cruise control system, and set DTC P0574.

Conditions for Running the DTC

    • Cruise control is enabled.
    • Cruise control is engaged.

Conditions for Setting the DTC

The PCM detects a vehicle speed greater than 176 km/h (110 mph).

Action Taken When the DTC Sets

    • The PCM disables cruise control.
    • The PCM will not illuminate the malfunction indicator lamp (MIL).
    • The PCM will store conditions which were present when the DTC set as Fail Records data only.

Conditions for Clearing the DTC

    • The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC can be cleared by using the scan tool Clear DTC Information function.

Diagnostic Aids

If the condition is intermittent, refer to Intermittent Conditions in Symptoms.

This diagnostic trouble code (DTC) is an information DTC only. The DTC indicates the reason that the PCM disabled the cruise control system. Be sure to verify with the customer the conditions that set the DTC. Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may assist in diagnosing the condition. The information may help determine how often the condition that set the DTC occurs.

Step

Action

Yes

No

1

Did you perform the Cruise Control Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Cruise Control

2

Since most occurrences of DTC P0574 are caused by wheel spin due to icy, wet or slippery conditions, verify the conditions under which the DTC set with the customer.

Did the road conditions cause this DTC to set?

Go to Step 3

Go to Diagnostic Aids

3

Explain system operation to the customer and clear this DTC.

Is the action complete?

System OK

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