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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1997 🢒 GMC P52 RV/Van Chassis 🢒 Body and Accessories 🢒 Cruise Control 🢒 Cruise Control Inoperative

Cruise Control Inoperative P72 When Switch is On

P72 Cruise Control Inoperative When Switch Is "ON"

Step

Action

Value(s)

Yes

No

1

Is the 20A ALT fuse blown?

--

Go to Step 2

Go to Step 3

2

Check for a short circuit. Repair if necessary and replace the fuse.

Is the repair complete?

--

System OK

--

3
  1. Ignition switch in RUN.
  2. Cruise control switch ON.
  3. Probe the PNK/BLK (39) wire at the cruise control switch connector with a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 4

4

Locate and repair the open PNK/BLK (39) wire.

Is the repair complete?

--

System OK

--

5
  1. Ignition ON.
  2. Cruise control switch ON.
  3. Probe the GRA (397) wire at the cruise control switch connector with a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 8

6

Replace the cruise control switch.

Is the repair complete?

--

System OK

--

7
  1. Ignition ON.
  2. Cruise control switch ON.
  3. Probe the GRA (397) wire at the powertrain control module (PCM) using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Does Not Operate with "Set" Switch Depressed

Go to Step 8

8

Locate and repair the open GRA (397) wire between the PCM and the cruise control switch.

Is the repair complete?

--

System OK

--

Cruise Control Inoperative P72With Set Switch Depressed

P72 Cruise Control Inoperative With Set Switch Depressed

Step

Action

Value(s)

Yes

No

1

Refer to Cruise Control Inoperative When Switch Is "ON" before using this table.

Is the other table completed?

--

Go to Step 2

Go to other table first

2
  1. Ignition switch in RUN.
  2. Cruise control switch ON.
  3. Probe the PNK/BLK (39) wire at the cruise control switch connector using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 3

3

Locate and repair the open in the PNK/BLK (39) wire.

Is the repair complete?

--

System OK

--

4
  1. Ignition ON.
  2. Cruise control switch ON.
  3. "SET" switch depressed.
  4. Use a grounded test lamp to probe the DK BLU (84) wire at the cruise control switch connector.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 5

5

Replace the cruise control switch.

Is the repair complete?

--

System OK

--

6
  1. Ignition ON.
  2. Cruise control switch ON.
  3. "SET" switch depressed.
  4. Probe the DK BLU (84) wire at the powertrain control module (PCM) using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 8

Go to Step 7

7

Locate and repair the open DK BLU (84) wire between the cruise control switch and the PCM.

Is the repair complete?

--

System OK

--

8

Replace the PCM.

Is the repair complete?

--

System OK

--

Cruise Control Inoperative P92 When Switch is On

P92 Cruise Control Inoperative When the Switch Is "On"

Step

Action

Value(s)

Yes

No

1
  1. Ignition switch in RUN.
  2. Cruise control switch ON.
  3. Probe the RED (274) wire at the cruise control switch connector with a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 3

Go to Step 2

2

Locate and repair the open RED (274) wire.

Is the repair complete?

--

System OK

--

3
  1. Ignition ON.
  2. Cruise control switch ON.
  3. Probe the GRN (276) wire at the cruise control switch connector using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 4

4

Replace the cruise control switch.

Is the repair complete?

--

System OK

--

5
  1. Ignition ON.
  2. Cruise control switch ON.
  3. Probe the GRN (276) wire at the powertrain control module (PCM) using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Does Not Operate with Set/Accel Switch Depressed

Go to Step 6

6

Locate and repair the open GRN (276) wire between the PCM and the cruise control switch.

Is the repair complete?

--

System OK

--