Component Tests and General Diagnostics
SCAN TOOL DIAGNOSTICSVerify that the CHECK ENGINE lamp is not lit. If the lamp is lit, check for DTCs first before diagnosing cruise control problems. Four DTCs could impact cruise control operation. These DTCs are the following:
^ P0505 - Idle Signal.
^ P0758 - Shift solenoid 2 signal.
^ P0120 - Throttle position sensor (TPS).
^ P0500 - Vehicle speed sensor (VSS).
^ P1780 - Park/Neutral Position (PNP) switch.
Scan Tool diagnostics are not available for the Prizm cruise control system.
FLASH DTC DIAGNOSTICS
Flash DTC diagnostics read current DTCs. You can enable FLASH DTC diagnostics by locating the Data Link Connector (DLC) which is in the LH rear of the engine compartment, mounted to the strut tower. Connect a jumper to terminal 11 (Tc) and terminal 3 (E1) with the ignition switch set to the ON position. This action pulls the cruise control module (CCM) terminal 5 to ground and signals the CCM to enter the FLASH DTC diagnostic display mode.
The CCM displays the DTCs by flashing the cruise control indicator lamp. Each DTC that is displayed consists of the following:
1. A series of flashes which represent the tens (first) DTC digit
2. A 2.5 second pause
3. A series of flashes which represent the ones (second) DTC digit
For example, a FLASH DTC of 32 would be displayed as: three flashes, a 2.5 second pause, and two more flashes. Each DTC is flashed once before moving on to the next DTC. After all the DTCs are displayed, the entire DTC sequence is continually repeated until you remove the jumper from the DLC.
If there are no DTCs present, the CCM will flash the CRUISE indicator lamp lamp continuously. This indicates that FLASH DTC diagnostics have been enabled. The SDM will continue to flash the Cruise indicator lamp until the jumper wire is removed from the DLC.
Diagnostic Chart:
FLASH CODE DTC TABLE
DIAGNOSTIC AIDS
Check for the following:
^ Open ECU-IG fuse.
^ Open ECU-B fuse.
^ Open STOP fuse.
^ Clean, tight G203.
In the case of an intermittent malfunction, inspect the wiring harness or component connectors for any of the following conditions:
^ Backed out terminals.
^ Improper mating of terminals.
^ Broken electrical connectors locks.
^ Improperly formed or damaged terminals
^ Faulty terminal to wire connections.
^ Physical damage to the wiring harness.
^ A broken wire inside the insulation.
^ Corrosion of electrical connections, splices, or terminals.
Repair any electrical circuit faults that were found. Refer to Wiring Repairs in Wiring Systems.
Cruise Control System Check (Part 1 Of 5):
Cruise Control System Check (Part 2 Of 5):
Cruise Control System Check (Part 3 Of 5):
Cruise Control System Check (Part 4 Of 5):
Cruise Control System Check (Part 5 Of 5):
TEST DESCRIPTION
Number(s) below refer to the step number(s) on the Diagnostic Table.
3. This step commands the cruise control module to enter the diagnostic mode and tests the cruise control switch in the SET/COAST position.
4. Steps 4-5 test the cruise control switch in the RES/ACC position.
6. This step tests the brake pedal stop lamp switch.
8. This step tests the PNP switch.
9. This step tests the clutch pedal position (CPP) interrupt switch.
10. This step tests the vehicle speed sensor (VSS).
11. This step tests for any flash code DTCs.
12. This step tests for either a short between the CCM and the Instrument cluster assembly or a faulty CCM.
16. This step tests the ability of the cruise control module to delay overdrive (OD) upshift when holding set speed under vehicle load.