GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2005 🢒 Park Avenue 🢒 Restraints 🢒 SIR 🢒 DTC P1554

Circuit Description

The powertrain control module (PCM) inhibits cruise control operation when certain conditions are detected.

The PCM removes the ground for the cruise control inhibit signal circuit in order to disengage cruise control operation. The cruise control module monitors the cruise control inhibit signal circuit in order to determine when to inhibit cruise. When the cruise control module (CCM) activates cruise control operation, the CCM provides a ground for the cruise control engaged signal circuit. The PCM monitors the cruise control engaged signal circuit in order to determine that the cruise control is engaged.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P1554 Cruise Control Feedback Circuit

Conditions for Running the DTC

The PCM inhibits cruise control operation by removing the ground for the cruise control inhibit signal circuit.

Conditions for Setting the DTC

The PCM detects a voltage on the cruise engaged signal circuit when the PCM inhibits cruise control operation.

Action Taken When the DTC Sets

The PCM stores the conditions present when the DTC set as Failure Records data only.

Conditions for Clearing the DTC
    • The history DTC clears after 40 malfunction free warm-up cycles.
    • The PCM receives a clear code command from the scan tool.

Step

Action

Yes

No

Schematic Reference: Cruise Control Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step  2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Install a scan tool.
  2. Turn the ignition ON, with the engine OFF.
  3. With a scan tool, observe the Cruise Control Active parameter in the powertrain control module (PCM) Engine Data 1 data list.

Does the Cruise Control Active parameter display Yes?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

  1. Turn the ignition OFF.
  2. Disconnect the cruise control module.
  3. Turn the ignition ON, with the engine OFF.
  4. Using the scan tool, observe the Cruise Control Active parameter.

Does the Cruise Control Active parameter display YES?

Go to Step 4

Go to Step 5

4
  1. Turn the ignition OFF.
  2. Test the cruise control engaged signal circuit for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 6

5

Inspect for poor connections at the harness connector of the cruise control module (CCM). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connection at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the CCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 9

--

8

Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 9

--

9
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK