GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2006 🢒 CTS 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Cruise Control Inoperative/Malfunctioning

Diagnostic Aids

Perform the following in order to avoid misdiagnosis:

    • Ensure that the following cruise control switches are not stuck in the engaged position:
       - On/Off switch
       - Set/Coast switch
       - Resume/Accel switch
    • Inspect for proper operation of the stop lamps. Refer to Exterior Lighting Systems Description and Operation .
    • Electromagnetic interference (EMI) on the speed sensor signal circuit may cause erratic cruise control operation.
    • Inspect for proper operation of the clutch pedal position (CPP) sensor and that DTC P0833 is not set as current or history. Refer to DTC P0833 if this DTC is set as current or history.
    • For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections .

Step

Action

Yes

No

Schematic Reference: Cruise Control Schematics

Connector End View Reference: Engine Control Module Connector End Views for the 2.8L engine or Engine Control Module Connector End Views for the 3.6L engine or Engine Control Module Connector End Views for the 6.0L engine

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Turn the cruise control On/Off switch OFF.
  4. With the scan tool, observe the following cruise control parameters in the Cruise/Traction Data list:
    5. • Cruise Resume/Accel Switch
    • Cruise Set/Coast Switch

Do any of the parameters listed above display ON?

Go to Step 5

Go to Step 3

3
  1. Turn the cruise control switch ON.
  2. With the scan tool, observe the Cruise Set/Coast Switch parameter.
  3. Press and hold the set/coast switch.

Does the Cruise Set/Coast Switch parameter display On?

Go to Step 4

Go to Step 6

4
  1. With the scan tool, observe the Cruise Resume/Accel Switch parameter.
  2. Press and hold the resume/accel switch.

Does the Cruise Resume/Accel Switch parameter display On?

Go to Diagnostic Aids

Go to Step 9

5
  1. Turn OFF the ignition.
  2. Disconnect C4 of the multifunction switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With the scan tool, observe the following cruise control parameters:
    5. • Cruise Resume/Accel Switch
    • Cruise Set/Coast Switch

Do any of the parameters listed above display On?

Go to Step 7

Go to Step 9

6
  1. Turn OFF the ignition.
  2. Disconnect C4 of the multifunction switch.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the ignition 1 voltage circuit and a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 11

7

Test the cruise control set/coast and resume/accel switch signal circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs .

Did you find and correct the condition?

Go to Step 14

Go to Step 10

8

Test the cruise control set/coast and resume/accel switch signal circuit for the following conditions:

    • An open
    • A short to ground
    • A short to voltage
    • High resistance

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 14

Go to Step 9

9

Inspect for poor connections at C4 the multifunction switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 14

Go to Step 12

10

Inspect for poor connections at the harness connector of the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 14

Go to Step 13

11

Repair an open, a short to ground, or a high resistance in the ignition 1 voltage circuit. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 14

--

12

Replace the cruise control switch. Refer to Turn Signal Multifunction Switch Replacement .

Did you complete the replacement?

Go to Step 14

--

13

Replace the ECM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 14

--

14

Operate the cruise control system in order to verify the repair.

Does the cruise control system operate properly?

System OK

Go to Step 2