Code No.P0578: Cruise Control Switch Stuck
Code No.P0579: Cruise Control Switch Range
Code No.P0580: Cruise Control Switch Low
Code No.P0581: Cruise Control Switch High
Code No.P0591, P0592, P0593: Cruise Control Component Driver Key Signal 2










OPERATION




  • When all switches are OFF: 4.7 - 5.0 volts
  • When the "ON/OFF" switch is ON: 0 - 0.5 volt
  • When the "CANCEL" switch is ON: 1.0 - 1.8 volts
  • When the "COAST/SET" switch is ON: 2.3 - 3.0 volts
  • When the "ACC/RES" switch is ON: 3.5 - 4.2 volts

DIAGNOSIS CODE SET CONDITIONS




POSSIBLE CAUSES



  • Damaged harness or connector.
  • Malfunction of the cruise control switch.
  • Malfunction of the clock spring.
  • Malfunction of the engine-ECU.

DIAGNOSIS

STEP 1. Check the data list.
Using M.U.T.-III, check the data list.

  • Item 285: Cruise control switch
(Refer to data list reference table ) <BSY>.

Q. Is the check result normal?
Go to Step 18.
Go to Step 2.

STEP 2. Measure the voltage at cruise control switch connector C-201.
(1)Remove the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ].
(2)Remove the cruise control switch from the steering wheel with the cruise control switch connector connected (Refer to ).
(3)Connect the negative battery terminal that was disconnected when the driver’s air bag module was removed.
(4)Turn the ignition switch to the "ON" position, and do not operate the cruise control switch (all the switches of the cruise control switch are OFF).
(5)Measure the voltage between cruise control switch connector C-201 terminal No. 3 and earth with cruise control switch connector C-201 connected.
OK: 4.7 - 5.0 V
(6)Turn the ignition switch to the "LOCK" (OFF) position.
(7)Install the cruise control switch to the steering wheel (Refer to ).

Q. Is the check result normal?
Go to Step 9.
Go to Step 3.

STEP 3. Measure the terminal voltage at engine-ECU connector B-05.
(1)Remove the engine-ECU (Refer to GROUP 13A - Engine-ECU ).
(2)Connect special tool power plant ECU check harness (MB992044) between the engine-ECU and the body-side harness connector.
(3)Turn the ignition switch to the "ON" position, and do not operate the cruise control switch (all the switches of the cruise control switch are OFF).
(4)Measure the voltage between special tool 60-pin connector terminal No. 52 (engine-ECU connector B-05 terminal No. 52) and earth (Refer to ).
OK: 4.7 - 5.0 V
(5)Turn the ignition switch to the "LOCK" (OFF) position.
(6)Disconnect special tool (MB992044) between the engine-ECU and the body-side harness connector.
(7)Install the engine-ECU (Refer to GROUP 13A - Engine-ECU ).

Q. Is the check result normal?
Go to Step 6.
Go to Step 4.

STEP 4. Connector check: B-05 engine-ECU connector.

Q. Is the check result normal?
Go to Step 5.
Repair or replace the damaged connector. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 5. Check the harness between engine-ECU connector B-05 terminal No. 52 and the cruise control switch connector C-201 terminal No. 3.
(1)Disconnect engine-ECU connector B-05 and measure at the harness connector side.
(2)Measure the continuity between engine-ECU connector B-05 terminal No. 52 and earth.
(3)Connect engine-ECU connector B-05.

Q. Is the measured continuity open circuit?
Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 17.
Go to Step 6.

STEP 6. Connectors check: C-201 cruise control switch connector, C-202 and C-204 clock spring connectors.

Q. Is the check result normal?
Go to Step 7.
Repair or replace the damaged connectors. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 7. Check the clock spring.
Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring Inspection .

Q. Is the check result normal?
Go to Step 8.
Replace the clock spring and install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 8. Check the harness between engine-ECU connector B-05 terminal No. 52 and the cruise control switch connector C-201 terminal No. 3.

Q. Is the check result normal?
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ). Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ].
Repair the damaged harness wire. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 9. Measure the voltage at cruise control switch connector C-201.
(1)Remove the cruise control switch from the steering wheel with the cruise control switch connector connected (Refer to ).
(2)Turn the ignition switch to the "ON" position.
(3)Press the "ON/OFF" switch with cruise control switch connector C-201 connected, and measure the voltage between terminal No. 2 and earth.
OK: 0.3 V or less
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Install the cruise control switch to the steering wheel (Refer to ).

Q. Is the check result normal?
Go to Step 15.
Go to Step 10.

STEP 10. Measure the terminal voltage at engine-ECU connector B-06.
(1)Remove the engine-ECU (Refer to GROUP 13A - Engine-ECU ).
(2)Connect special tool power plant ECU check harness (MB992044) between the engine-ECU and the body-side harness connector.
(3)Turn the ignition switch to the "ON" position.
(4)Press the "ON/OFF" switch, and measure the voltage between special tool 94-pin connector terminal No. 68 (engine-ECU connector B-06 terminal No. 128) and earth (Refer to ).
OK: 0.3 V or less
(5)Turn the ignition switch to the "LOCK" (OFF) position.
(6)Disconnect special tool (MB992044) between the engine-ECU and the body-side harness connector.
(7)Install the engine-ECU (Refer to GROUP 13A - Engine-ECU ).

Q. Is the check result normal?
Go to Step 12.
Go to Step 11.

STEP 11. Connector check: B-06 engine-ECU connector.

Q. Is the check result normal?
Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 17.
Repair or replace the damaged connector. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 12. Connectors check: B-06 engine-ECU connector, C-201 cruise control switch connector, C-202 and C-204 clock spring connectors.

Q. Is the check result normal?
Go to Step 13.
Repair or replace the damaged connectors. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 13. Check the clock spring.
Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring Inspection .

Q. Is the check result normal?
Go to Step 14.
Replace the clock spring and install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 14. Check the harness between engine-ECU connector B-06 terminal No. 128 and the cruise control switch connector C-201 terminal No. 2.

Q. Is the check result normal?
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ). Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ].
Repair the damaged harness wire. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 15. Connector check: C-201 cruise control switch connector.

Q. Is the check result normal?
Go to Step 16.
Repair or replace the damaged connector. Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 16. Check the cruise control switch.
Refer to .

Q. Is the check result normal?
Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 17.
Replace the cruise control switch (Refer to ). Install the driver’s air bag module [Refer to GROUP 52B - Driver’s, Front Passenger’s Air Bag Module(s) and Clock Spring ]. Then go to Step 19.

STEP 17. Check the data list.
Using M.U.T.-III, check the data list.

  • Item 285: Cruise control switch
(Refer to data list reference table ) <BSY>.

Q. Is the check result normal?
Go to Step 18.
Replace the engine-ECU (Refer to GROUP 13A - Engine-ECU ). Then go to Step 19.

STEP 18. Read the diagnosis code.
Using M.U.T.-III, read the diagnosis code of the cruise control system (Refer to ).

Q. Is diagnosis code No. P0578, P0579, P0580, P0581, P0591, P0592 or P0593 set?
Replace the engine-ECU (Refer to GROUP 13A - Engine-ECU ). Then go to Step 19.
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ).

STEP 19. Check the data list.
Using M.U.T.-III, check the data list.

  • Item 285: Cruise control switch
(Refer to data list reference table ) <BSY>.

Q. Is the check result normal?
Go to Step 20.
Return to Step 2.

STEP 20. Read the diagnosis code.
Using M.U.T.-III, read the diagnosis code of the cruise control system (Refer to ).

Q. Is diagnosis code No. P0578, P0579, P0580, P0581, P0591, P0592 or P0593 set?
Return to Step 1.
The procedure is complete.