Circuit Description
The powertrain control module (PCM) inhibits cruise control operation when certain conditions are not appropriate for cruise control operation. The PCM removes the ground from the cruise control inhibit signal circuit in order to disengage cruise control operation.
Conditions for Running the DTC
The PCM is commanding the stepper motor cruise control (SMCC) module to inhibit cruise control operation. The cruise inhibit circuit is not grounded.
Conditions for Setting the DTC
| • | The cruise status circuit signal indicates that the cruise control is engaged. |
| • | The above conditions are present for more than 1 second. |
Action Taken When the DTC Sets
The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.
Conditions for Clearing the MIL/DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction free warm-up cycles. |
| • | The PCM receives a clear code command from the scan tool. |
Diagnostic Aids
Check for the following conditions:
| • | A faulty connection at the PCM. Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connections. Use a corresponding mating terminal to test for proper terminal tension. |
| • | Inspect the wiring harness for damage. If the harness appears to be OK, observe the Cruise Status display on the scan tool while moving the connectors and wiring harnesses related to the SMCC module. A change in the display will indicate the location of the malfunction. |
If DTC P1554 cannot be duplicated, the information included in the Failure Records data can be useful in determining how many ignition cycles have passed since the DTC was last set.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Was the Powertrain On Board Diagnostic (OBD) System Check performed? | -- | ||
2 |
Is the voltage approximately equal to the specified value? | B+ | ||
3 |
Does the test lamp illuminate? | -- | ||
4 |
Does the test lamp illuminate? | -- | ||
5 | Replace the cruise control module. Refer to Cruise Control Module Replacement in Cruise Control. Did you complete the repair? | -- | -- | |
|
Important:: The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the repair? | -- | -- | ||
7 | Locate and repair a short to ground in the cruise engaged status circuit. Refer to Wiring Repairs in Wiring Systems . Did you complete the repair? | -- | -- | |
8 |
Did DTC P1554 set? | -- | System OK |
