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DTC 15




DTC 15: Cruise Control Switch System

















CIRCUIT OPERATION

This circuit judges the signals of each switch ("ON/OFF", "CANCEL", "COAST/SET" and
"ACC/RES") of the cruise control switch. The ECM detects the state of the cruise control switch by sensing the voltages shown below.

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


DTC SET CONDITIONS

Check Condition

- The "CRUISE" indicator light illuminates.
Judgment Criteria

- This DTC is set when the ECM terminal voltage is different from the standard value.
- Or, this DTC is set when the "COAST/SET" switch or "ACC/RES" switch is stuck to ON.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)

- Damaged harness or connector.
- Malfunction of the cruise control switch.
- Malfunction of the clock spring.
- Malfunction of the ECM.

DIAGNOSTIC PROCEDURE

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
- MB991223: Harness Set
- MB992006: Extra Fine Probe
- MB992110: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check the data list item 75: Cancel switch, item 86: Main switch, item 91: Resume switch and item 92: Set switch.





(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK"
(OFF) position before connecting or disconnecting scan tool MB991958.

Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)

- Item 75: Cancel switch.
- When "CANCEL" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "CANCEL" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 86: Main switch.
- When "ON/OFF" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ON/OFF" switch is pressed again, the display on scan tool MB991958 should be "OFF".
- Item 91: Resume switch.
- When "ACC/RES" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ACC/RES" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 92: Set switch.
- When "COAST/SET" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "COAST/SET" switch is released, the display on scan tool MB991958 should be "OFF".

Q. Is the switch operating properly?

YES Go to Step 25.

NO Go to Step 2.

STEP 2. Measure the power supply voltage at cruise control switch connector C-201 by backprobing.

(1)Remove the cruise control switch from the steering wheel with the cruise control switch connector connected (Refer to Service and Repair.)

(2)Connect the negative (-) battery cable that was disconnected when the driver's air bag module was removed.

(3)Do not disconnect cruise control switch connector C-201.

(4)Turn the ignition switch to the "ON" position.

(5)Do not operate the cruise control switch.





(6)Measure the power supply voltage between cruise control switch connector C-201 terminal number 3 and body ground by backprobing.

Q. Is the measured voltage between 4.7 and 5.0 volts?

YES Go to Step 14.

NO Go to Step 3.

STEP 3. Measure the power supply voltage at ECM connector B-10.

(1)Remove the ECM [ Removal and Replacement.]





(2)Connect special tool MB992110 between the ECM and the body-side harness connector.
(3)Turn the ignition switch to the "ON" position.
(4)Do not operate the cruise control switch.





(5)Measure the power supply voltage between special tool 48-pin connector terminal number 107 (ECM connector B-10 terminal number 107) and body ground.

Q. Is the measured voltage between 4.7 and 5.0 volts?

YES Go to Step 10.

NO Go to Step 4.

STEP 4. Check ECM connector B-10 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Harness Connector Inspection.

Q. Is the connector and terminal in good condition?

YES Go to Step 5.
NO Repair or replace the damaged connector. Then go to Step 26.
STEP 5. Check the harness wire for short circuit to body ground between the ECM connector B-10 terminal number 107 and the cruise control switch connector C-201 terminal number 3.

(1)Disconnect ECM connector B-10 and measure at the harness connector side [ Removal and Replacement.]

(2)Turn the ignition switch to the "LOCK" (OFF) position.





(3)Measure the continuity between ECM connector B-10 terminal number 107 and body ground.

Q. Is the measured continuity open circuit?

YES Go to Step 24.

NO Go to Step 6.

STEP 6. Check intermediate connector C-131, cruise control switch connector C-201, and clock spring connectors C-202 and C-205, for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Harness Connector Inspection.

Q. Is the connector and terminal in good condition?

YES Go to Step 7.
NO Repair or replace the damaged connector. Then go to Step 26.
STEP 7. Check the harness wire between ECM connector B-10 terminal number 107 and clock spring connector C-205 terminal number 5, and between clock spring connector C-202 terminal number 2 and cruise control switch connector C-201 terminal number 3, for damage.

- Check harness wire for short circuit and damage.

Q. Is the harness wires in good condition?

YES Go to Step 8.
NO Repair or replace the damaged harness wire. Then go to Step 26.
STEP 8. Check the clock spring.

Testing and Inspection.

Q. Is the clock spring in good condition?

YES Go to Step 9.
NO Replace the clock spring Removal and Installation.) Then go to Step 26.
STEP 9. Check the cruise control switch.

Refer to Component Tests and General Diagnostics.

Q. Is the cruise control switch operating properly?

YES Go to Step 13.
NO Replace the cruise control switch (Refer to Service and Repair.) Then go to Step 26.
STEP 10. Check ECM connector B-10, intermediate connector C-131, cruise control switch connector C-201, and clock spring connectors C-202 and C-205, for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Harness Connector Inspection.

Q. Is the connector and terminal in good condition?

YES Go to Step 11.
NO Repair or replace the damaged connector. Then go to Step 26.
STEP 11. Check the harness wire between ECM connector B-10 terminal number 107 and clock spring connector C-205 terminal number 5, and between clock spring connector C-202 terminal number 2 and cruise control switch connector C-201 terminal number 3, for damage.

- Check harness wire for open circuit and damage.

Q. Is the harness wires in good condition?

YES Go to Step 12.
NO Repair or replace the damaged harness wire. Then go to Step 26.
STEP 12. Check the clock spring.

Testing and Inspection.

Q. Is the clock spring in good condition?

YES Go to Step 13.
NO Replace the clock spring Removal and Installation.) Then go to Step 26.
STEP 13. Using scan tool MB991958, check data list item 75: Cancel switch, item 86: Main switch, item 91: Resume switch and item 92: Set switch.

(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)

(2)Turn the ignition switch to the "ON" position.

(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)

- Item 75: Cancel switch.
- When "CANCEL" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "CANCEL" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 86: Main switch.
- When "ON/OFF" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ON/OFF" switch is pressed again, the display on scan tool MB991958 should be "OFF".
- Item 91: Resume switch.
- When "ACC/RES" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ACC/RES" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 92: Set switch.
- When "COAST/SET" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "COAST/SET" switch is released, the display on scan tool MB991958 should be "OFF".

Q. Is the switch operating properly?

YES Go to Step 25.
NO Go to Step 14.
STEP 14. Measure the ground voltage at cruise control switch connector C-201 by backprobing.

(1)Remove the cruise control switch from the steering wheel with the cruise control switch connector connected (Refer to Service and Repair.)

(2)Connect the negative (-) battery cable that was disconnected when the driver's air bag module was removed.

(3)Do not disconnect cruise control switch connector C-201.

(4)Turn the ignition switch to the "ON" position.





(5)Press and hold the "ON/OFF" switch, and measure the ground voltage between cruise control switch connector C-201 terminal number 2 and body ground by backprobing.

Q. Is the measured voltage 0.5 volt or less?

YES Go to Step 20.

NO Go to Step 15.

STEP 15. Measure the ground voltage at ECM connector B-10.

(1)Remove the ECM [ Removal and Replacement.]

(2)Connect special tool MB992110 between the ECM and the body-side harness connector.

(3)Turn the ignition switch to the "ON" position.





(4)Press and hold the "ON/OFF" switch, and measure the ground voltage between special tool 48-pin connector terminal number 95 (ECM connector B-10 terminal number 95) and body ground.

Q. Is the measured voltage 0.5 volt or less?

YES Go to Step 17.

NO Go to Step 16.

STEP 16. Check ECM connector B-10 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Harness Connector Inspection.

Q. Is the connector and terminal in good condition?

YES Go to Step 24.
NO Repair or replace the damaged connector. Then go to Step 26.
STEP 17. Check intermediate connector C-131, cruise control switch connector C-201, and clock spring connectors C-202 and C-205, for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Harness Connector Inspection.

Q. Is the connector and terminal in good condition?

YES Go to Step 18.
NO Repair or replace the damaged connector. Then go to Step 26.
STEP 18. Check the harness wire between cruise control switch connector C-201 terminal number 2 and clock spring connector C-202 terminal number 3, and between clock spring connector C-205 terminal number 4 and ECM connector B-10 terminal number 95, for damage.

- Check harness wire for open circuit and damage.

Q. Is the harness wires in good condition?

YES Go to Step 19.
NO Repair or replace the damaged harness wire. Then go to Step 26.
STEP 19. Check the clock spring.

Testing and Inspection.

Q. Is the clock spring in good condition?

YES Go to Step 24.
NO Replace the clock spring Removal and Installation). Then go to Step 26.
STEP 20. Check ECM connector B-10, intermediate connector C-131, cruise control switch connector C-201, and clock spring connectors C-202 and C-205, for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Harness Connector Inspection.

Q. Is the connector and terminal in good condition?

YES Go to Step 21.
NO Repair or replace the damaged connector. Then go to Step 26.
STEP 21. Check the harness wire between cruise control switch connector C-201 terminal number 2 and clock spring connector C-202 terminal number 3, and between clock spring connector C-205 terminal number 4 and ECM connector B-10 terminal number 95, for damage.

- Check harness wire for short circuit and damage.

Q. Is the harness wires in good condition?

YES Go to Step 22.
NO Repair or replace the damaged harness wire. Then go to Step 26.
STEP 22. Check the clock spring.

Testing and Inspection.

Q. Is the clock spring in good condition?

YES Go to Step 23.
NO Replace the clock spring Removal and Installation.) Then go to Step 26.
STEP 23. Check the cruise control switch.

Refer to Component Tests and General Diagnostics.

Q. Is the cruise control switch operating properly?

YES Go to Step 24.
NO Replace the cruise control switch (Refer to Service and Repair.) Then go to Step 26.
STEP 24. Using scan tool MB991958, check data list item 75: Cancel switch, item 86: Main switch, item 91: Resume switch and item 92: Set switch.

(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)

(2)Turn the ignition switch to the "ON" position.

(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)

- Item 75: Cancel switch.
- When "CANCEL" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "CANCEL" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 86: Main switch.
- When "ON/OFF" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ON/OFF" switch is pressed again, the display on scan tool MB991958 should be "OFF".
- Item 91: Resume switch.
- When "ACC/RES" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ACC/RES" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 92: Set switch.
- When "COAST/SET" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "COAST/SET" switch is released, the display on scan tool MB991958 should be "OFF".

Q. Is the switch operating properly?

YES Go to Step 25.
NO Replace the ECM [ Removal and Replacement.] Then go to Step 26.
STEP 25. Read the cruise control system DTC.

(1)Disconnect the negative (-) battery terminal, to erase the DTC of the cruise control system.

(2)Connect the negative (-) battery terminal.

(3)Turn the ignition switch to the "ON" position, and press the "ON/OFF" switch to turn the cruise control system to ON (turn on the "CRUISE" indicator light.)

(4)After turning the cruise control system to ON, when 2 minutes or more has elapsed without operating the cruise control switches, read the DTC of the cruise control system (Refer to Reading and Clearing Diagnostic Trouble Codes.)

Q. Is DTC 15 set?

YES Replace the ECM [ Removal and Replacement.] Then go to Step 26.
NO It can be assumed that this malfunction is intermittent How to Cope With Intermittent Malfunctions.)
STEP 26. Using scan tool MB991958, check data list item 75: Cancel switch, item 86: Main switch, item 91: Resume switch and item 92: Set switch.

(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)

(2)Turn the ignition switch to the "ON" position.

(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)

- Item 75: Cancel switch.
- When "CANCEL" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "CANCEL" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 86: Main switch.
- When "ON/OFF" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ON/OFF" switch is pressed again, the display on scan tool MB991958 should be "OFF".
- Item 91: Resume switch.
- When "ACC/RES" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "ACC/RES" switch is released, the display on scan tool MB991958 should be "OFF".
- Item 92: Set switch.
- When "COAST/SET" switch is pressed, the display on scan tool MB991958 should be "ON".
- When "COAST/SET" switch is released, the display on scan tool MB991958 should be "OFF".

Q. Is the switch operating properly?

YES Go to Step 27.
NO Return to Step 2.
STEP 27. Read the cruise control system DTC.

(1)Disconnect the negative (-) battery terminal, to erase the DTC of the cruise control system.

(2)Connect the negative (-) battery terminal.

(3)Turn the ignition switch to the "ON" position, and press the "ON/OFF" switch to turn the cruise control system to ON (turn on the "CRUISE" indicator light.)

(4)After turning the cruise control system to ON, when 2 minutes or more has elapsed without operating the cruise control switches, read the DTC of the cruise control system (Refer to Reading and Clearing Diagnostic Trouble Codes.)

Q. Is DTC 15 set?

YES Return to Step 1.
NO The procedure is complete.