GM Service Manual Online
For 1990-2009 cars only

Object Number: 155143  Size: MF
Engine Controls Components
Cell 20: Cruise Control Module
OBD II Symbol Description Notice
ESD Notice

Circuit Description

This diagnostic test indicates that cruise control and traction control are active at the same time. It is a protective measure to disable the cruise control for example, when traveling on icy roads and traction control requests a maximum torque of less than 1 percent. Under these conditions DTC P1570 is set and the cruise control will be disengaged. The driver should be advised why the cruise disengaged. Clear the DTC and road test vehicle to verify normal operation.

Conditions for Running the DTC

Cruise control engaged.

Conditions for Setting the DTC

Traction control desired maximum torque less than 1% for 3 seconds.

Action Taken When the DTC Sets

PCM disables cruise control.

    •  The Malfunction Indicator Lamp (MIL) will not illuminate.
    •  No message will be displayed.

Conditions for Clearing the DTC

    •  A History DTC will clear after forty consecutive warm-up cycles with no failures of any non-emission related diagnostic test.
    •  A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.
    • Use a scan tool to clear DTCs.
    • Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation.

Diagnostic Aids

Reviewing the Failure Rec. may help diagnose an intermittent failure by showing how long ago and under what conditions the DTC set.

Clear the DTC and operate the vehicle under the conditions in which the DTC set if a fault condition is suspected.

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Using a scan tool check for traction control DTCs.

Are any traction control DTCs set?

--

Go to DTCs that are set

Go to Step 3

3

Since most occurrences of DTC P1570 are caused by wheelspin due to icy, wet or slippery conditions, check with the customer to verify the conditions under which the DTC set.

Did the road conditions cause this DTC to set?

--

Go to Step 4

Fault not present. Refer to Diagnostic Aids

4

Explain system operation to the customer and clear this DTC.

Is the repair complete?

--

System OK

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