P1554

Diagnostic Chart:

Schematic:

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) has the ability to disable cruise control if conditions are detected which would make cruise control operation undesirable. The following conditions may cause cruise control to be inhibited by the PCM:
^ Engine not running long enough for cruise control operation.
^ Transaxle range switch indicates Park, Neutral, Low, or Reverse gear selected.
^ Engine speed is too high or too low.
^ Vehicle speed is too high or too low.
^ ABS is active for longer than 2 seconds.
^ Vehicle acceleration or deceleration rate is too high.

If any of these conditions are present, the PCM will interrupt the ground on the cruise inhibit circuit to request that cruise control be disengaged. If the cruise status signal indicates that cruise control is still engaged while the PCM is inhibiting cruise control operation, DTC P1554 will set.

CONDITIONS FOR SETTING THE DTC
^ The PCM is commanding the SMCC module to inhibit cruise control operation. Cruise Inhibit circuit not grounded.
^ The Cruise Status circuit signal indicates that cruise control is engaged.
^ The above conditions are 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.