Chart C-17 Cruise Control System Check

Cruise Control System Diagnostic Chart:

Cruise Control System Diagnostic Chart (Part 2 Of 2):

Cruise Control System Circuit:

CIRCUIT DESCRIPTION
Cruise control operation is one of the functions which is Powertrain Control Module (PCM) controlled. The PCM receives input signals from the cruise control engagement switches, the Torque Converter Clutch (TCC) and cruise brake switches, the vehicle speed sensor, the Throttle Position (TP) sensor and the Servo Position Sensor (SPS). The PCM processes these inputs and sends output signals to the servo to open or close its vent and vacuum solenoid valves to control vehicle speed.

DIAGNOSTIC AIDS
An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation.
Check for:
^ Poor connection or damaged harness - Inspect PCM harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness.
^ If one or more of the following diagnostic trouble codes are stored, cruise control may be disabled. Repair any Diagnostic Trouble Codes (DTC)'s before diagnosing the cruise control system.
^ PO122 - TP Sensor Low.
^ PO123 - TP Sensor High.
^ PO5O1/PO5O2 - Vehicle Speed Sensor (VSS) Circuit.
^ PO7O3 - TCC Brake Switch Circuit Problem.
^ PO755 - Transaxle Shift B Solenoid Problem.
^ P1558 - Cruise System Problem (SPS indicated low).
^ P1561 - Cruise Vent Solenoid Circuit Problem.
^ P1562 - Cruise Vacuum Solenoid Circuit Problem.
^ P1565 - Cruise SPS Circuit Problem.
^ P1567 - Cruise Switch Problem.
^ P1568 - Cruise System Problem (SPS indicated high).
^ P163O - System Voltage High or Low.

Malfunction Indicator Lamp (MIL) is turned "ON" when this DTC is detected.