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For 1990-2009 cars only

Cruise Control Does Not Disengage with Brake Pedal Depressed, P72

P72 Cruise Control Does Not Disengage When Brake Pedal Is Depressed

Step

Action

Value(s)

Yes

No

1

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

Does the test lamp illuminate?

--

Go to Step 3

Go to Step 2

2

Locate and repair the open PNK/BLK (39) wire between the ALT fuse and the brake pedal connector.

Is the repair complete?

--

System OK

--

3

  1. Ignition ON.
  2. Cruise control switch ON.
  3. Depress the brake pedal.
  4. Probe the YEL (820) wire at the brake pedal switch connector using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 4

4

Replace the brake pedal switch.

Is the repair complete?

--

System OK

--

5

  1. Ignition ON.
  2. Cruise control switch ON.
  3. Depress the brake pedal.
  4. Probe the YEL (820) wire at the powertrain control module (PCM) using a grounded test lamp.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 6

6

Locate and repair the open YEL (820) wire between the brake pedal switch connector and the PCM.

Is the repair complete?

--

System OK

--

7

Replace the PCM.

Is the repair complete?

--

System OK

--

Cruise Control Does Not Disengage with Brake Pedal Depressed, P92

P92 Cruise Control Does Not Disengage When Brake Pedal Is Depressed

Step

Action

Value(s)

Yes

No

1

Check the brake switch.

Is the brake switch OK?

--

Go to Step 3

Go to Step 2

2

Replace the brake switch.

Is the repair complete?

--

System OK

--

3

  1. Ignition OFF.
  2. Check for continuity of the RED (27B) wire between the cruise control module and the interface panel using an ohmmeter>

Is the wire open?

--

Go to Step 4

Go to Step 5

4

Repair the open RED (27B) wire between the cruise control module and the interface panel.

Is the repair complete?

--

System OK

--

5

  1. Ignition OFF.
  2. Check for continuity of the RED (27B) wire between the interface panel and the brake switch using an ohmmeter.

Is the wire open?

--

Go to Step 6

Go to Step 7

6

Repair the open RED (27B) wire between the interface panel and the brake switch.

Is the repair complete?

--

System OK

--

7

Check the ground for the brake switch.

Is the ground bad?

--

Go to Step 8

Go to Diagnostic Aids

8

Repair the ground.

Is the repair complete?

--

System OK

--