Part 2
DIAGNOSTIC ITEM 27: Short to power supply or ground in both CAN_H and CAN_L lines.
STEP 18. Check the wiring harness between joint connector (CAN1) C-06 and radio and CD player connector C-104 for a short to power supply. Measure the voltage at joint connector (CAN1) C-06.
CAUTION:
A digital multimeter should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
CAUTION:
The test wiring harness should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
(1)Disconnect joint connector (CAN1), and measure the voltage at the wiring harness side of joint connector (CAN1).
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between joint connector (CAN1) terminal 6 and body ground.
OK: 4.7 V or less
(4)Measure the voltage between joint connector (CAN1) terminal 17 and body ground.
OK: 4.7 V or less
Q. Do all the voltages measure 4.7 V or less?
YES [vehicles without satellite radio] : Go to Step 21.
YES [vehicles with satellite radio] : Go to Step 20.
NO : Go to Step 28.
STEP 19. Check the wiring harness between joint connector (CAN1) C-06 and CAN box unit connector C-108 for a short to power supply. Measure the voltage at joint connector (CAN1) C-06.
CAUTION:
A digital multimeter should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
CAUTION:
The test wiring harness should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
(1)Disconnect joint connector (CAN1), and measure the voltage at the wiring harness side of joint connector (CAN1).
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between joint connector (CAN1) terminal 6 and body ground.
OK: 4.7 V or less
(4)Measure the voltage between joint connector (CAN1) terminal 17 and body ground.
OK: 4.7 V or less
Q. Do all the voltages measure 4.7 V or less?
YES [vehicles without satellite radio] : Go to Step 21.
YES [vehicles with satellite radio] : Go to Step 20.
NO : Go to Step 29.
STEP 20. Check the wiring harness between joint connector (CAN1) C-06 and satellite radio tuner connector C-17 for a short to power supply. Measure the voltage at joint connector (CAN1) C-06.
CAUTION:
A digital multimeter should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
CAUTION:
The test wiring harness should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
(1)Disconnect joint connector (CAN1), and measure the voltage at the wiring harness side of joint connector (CAN1).
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between joint connector (CAN1) terminal 3 and body ground.
OK: 4.7 V or less
(4)Measure the voltage between joint connector (CAN1) terminal 14 and body ground.
OK: 4.7 V or less
Q. Do all the voltages measure 4.7 V or less?
YES Go to Step 21.
NO Go to Step 30.
STEP 21. Check the wiring harness between joint connector (CAN1) C-06 and ETACS-ECU connector C-301 for a short to power supply. Measure the voltage at joint connector (CAN1) C-06.
CAUTION:
A digital multimeter should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
CAUTION:
The test wiring harness should be used. For details refer to Precautions When CAN Bus Line(s) are Repaired.
(1)Disconnect joint connector (CAN1), and measure the voltage at the wiring harness side of joint connector (CAN1).
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between joint connector (CAN1) terminal 11 and body ground.
OK: 4.7 V or less
(4)Measure the voltage between joint connector (CAN1) terminal 22 and body ground.
OK: 4.7 V or less
Q. Do all the voltages measure 4.7 V or less?
YES Go to Step 31.
NO Repair the wiring harness between joint connector (CAN1) C-06 and ETACS-ECU connector C-301.
STEP 22. Using scan tool MB991958, diagnose the CAN bus line. (checking the combination meter for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect combination meter connector C-04.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and combination meter connector C-04.
NO Check combination meter connector C-04, and repair if necessary. If the combination meter connector is in good condition, replace the combination meter.
STEP 23. Using scan tool MB991958, diagnose the CAN bus line. (checking the KOS-ECU for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect KOS-ECU connector C-31.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and KOS-ECU connector C-31.
NO Check KOS-ECU connector C-31, and repair if necessary. If the KOS-ECU connector is in good condition, replace the KOS-ECU.
STEP 24. Using scan tool MB991958, diagnose the CAN bus line. (checking the WCM for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect WCM connector C-09.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and WCM connector C-09.
NO Check WCM connector C-09, and repair if necessary. If the WCM connector is in good condition, replace the WCM.
STEP 25. Using scan tool MB991958, diagnose the CAN bus line. (checking the SRS-ECU for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect SRS-ECU connector C-122.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and SRS-ECU connector C-122.
NO Check SRS-ECU connector C-122, and repair if necessary. If the SRS-ECU connector is in good condition, replace the SRS-ECU.
STEP 26. Using scan tool MB991958, diagnose the CAN bus line. (checking the occupant classification-ECU for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect occupant classification-ECU connector D-35-2.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and occupant classification-ECU connector D-35-2.
NO Check occupant classification-ECU connector D-35-2, and repair if necessary. If the occupant classification-ECU connector is in good condition, replace the occupant classification-ECU.
STEP 27. Using scan tool MB991958, diagnose the CAN bus line. (checking the A/C-ECU [vehicles with A/C] or heater control unit [vehicles without A/C]
for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect A/C-ECU connector C-20 [vehicles with A/C] or heater control unit connector C-48 [vehicles without A/C].
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and A/C-ECU connector C-20 [vehicles with A/C] or heater control unit connector C-48 [vehicles without A/C].
NO Check A/C-ECU connector C-20 [vehicles with A/C] or heater control unit connector C-48 [vehicles without A/C], and repair if necessary. If the A/C-ECU [vehicles with A/C] or heater control unit connector [vehicles without A/C] connector is in good condition, replace the A/C-ECU [vehicles with A/C] or heater control unit [vehicles without A/C].
STEP 28. Using scan tool MB991958, diagnose the CAN bus line. (checking the radio and CD player for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect radio and CD player connector C-104.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and radio and CD player connector C-104.
NO Check radio and CD player connector C-104, and repair if necessary. If the radio and CD player connector is in good condition, replace the radio and CD player.
STEP 29. Using scan tool MB991958, diagnose the CAN bus line. (checking the CAN box unit for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect CAN box unit connector C-108.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and CAN box unit connector C-108.
NO Check CAN box unit connector C-108, and repair if necessary. If the CAN box unit connector is in good condition, replace the CAN box unit.
STEP 30. Using scan tool MB991958, diagnose the CAN bus line. (checking the satellite radio tuner for internal failure)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Disconnect satellite radio tuner connector C-17.
(2)Connect scan tool MB991958 to the data link connector.
(3)Turn the ignition switch to the "ON" position.
(4)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES Repair the wiring harness between joint connector (CAN1) C-06 and satellite radio tuner connector C-17.
NO Check satellite radio tuner connector C-17, and repair if necessary. If the satellite radio tuner connector is in good condition, replace the satellite radio tuner.
STEP 31. Using scan tool MB991958, diagnose the CAN bus line. (trouble symptom check)
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
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.
(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the figure.
OK: The display of the scan tool MB991958 is as shown in the figure.
Q. Does scan tool MB991958 screen correspond to the illustration?
YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
NO Check the ETACS-ECU connector C-301, and repair if necessary. If the ETACS-ECU connector is in good condition, replace the ETACS-ECU.