P1554

Refer to Engine Controls Schematics.

Diagnostic Chart:

CIRCUIT DESCRIPTION
The stepper motor cruise control module sends the cruise status input to the PCM to indicate when cruise control is engaged. The PCM monitors the cruise status signal while commanding cruise to be disengaged by grounding the cruise inhibit circuit. Any of the following conditions may cause the PCM to inhibit cruise control operation:
^ Engine is not running long enough for cruise control operation.
^ Transaxle range inputs indicate park, neutral, low, or reverse gear is selected.
^ Engine speed is too high or too low.
^ Vehicle speed is too high or too low.
^ TCS is active for longer than 2 seconds.
^ Vehicle acceleration or deceleration rate is too high.

CONDITIONS FOR RUNNING THE DTC
The PCM is commanding the cruise control module to not allow cruise control operation (cruise Inhibit circuit grounded).

CONDITIONS FOR SETTING THE DTC
^ The Cruise Status input to the PCM indicates that cruise control is still active.
^ The conditions is present for longer than 1 second.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using a scan tool.

DIAGNOSTIC AIDS
Inspect for the following conditions:

IMPORTANT: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

^ Poor terminal connection-Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Use a corresponding mating terminal to test for proper tension.
^ Damaged harness-Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault.
^ PCM and engine grounds for clean and secure connections

If the DTC is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
7. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.