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Troubleshooting diagnostic procedure

U2142-00: (CMU) TROUBLESHOOTING AND POSSIBLE CAUSE (WITH EMERGENCY CALL SYSTEM)

Step Inspection Results Action
1 PURPOSE: VERIFY REPEATABILITY 
  • Switch the ignition ON (engine off or on)/main power ON (READY off or on).
  • Clear the DTC recorded in the memory. (See CLEARING DTC .)
  • Switch the ignition off/main power OFF, and then switch it ON (READY off or on) and wait for 30 s or more.
  • Perform the DTC inspection for the connectivity master unit (CMU). (See DTC INSPECTION .)
  • Is the same Pending DTC present?
 Yes Go to the next step.
No Go to repair completion verification 2.
2 PURPOSE: VERIFY EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT DTC 
  • Perform the DTC inspection for the emergency call unit/telematics communication unit. (See DTC INSPECTION .)
  • Are any DTCs displayed?
 Yes Repair or replace the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [TCU] .)
No Go to the next step.
3 PURPOSE: VERIFY VOLTAGE SUPPLIED TO EMERGENCY CALL SPEAKER/MICROPHONE 
  • Measure the voltage at emergency call speaker/microphone terminal B (wiring harness-side).
  • Is the voltage approx. 8.0 V?
 Yes Go to Step 5.
No Go to the next step.
4 PURPOSE: VERIFY VOLTAGE WHICH EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT IS SUPPLYING 
  • Measure the voltage at emergency call unit/telematics communication unit terminal 1E (wiring harness-side).
  • Is the voltage approx. 8.0 V?
 Yes Go to the next step.
No Replace the emergency call unit/telematics communication unit and perform the repair completion verification 1.
(Refer to [EMERGENCY CALL UNIT REMOVAL/INSTALLATION] in service information.)
(Refer to TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION in service information.)
5 PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN EMERGENCY CALL SPEAKER/MICROPHONE AND EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT FOR MALFUNCTION 
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
6 PURPOSE: VERIFY VOLTAGE SUPPLIED FROM EMERGENCY CALL SPEAKER/MICROPHONE CONTROL CIRCUIT 
  • Measure the voltage at emergency call speaker/microphone terminal D (wiring harness-side).
  • Is the voltage approx. 8.0 V?
 Yes Replace the emergency call speaker/microphone and perform the repair completion verification 1.
(Refer to EMERGENCY CALL SPEAKER/MICROPHONE REMOVAL/INSTALLATION in service information.)
No Go to the next step.
7 PURPOSE: VERIFY VOLTAGE SUPPLIED AT CONTROL CIRCUIT CONTROLLED BY EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT 
  • Measure the voltage at emergency call unit/telematics communication unit terminal 1Y (wiring harness-side).
  • Is the voltage approx. 8.0 V?
 Yes Go to the next step.
No Replace the emergency call unit/telematics communication unit and perform the repair completion verification 1.
(Refer to [EMERGENCY CALL UNIT REMOVAL/INSTALLATION] in service information.)
(Refer to TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION in service information.)
8 PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN EMERGENCY CALL SPEAKER/MICROPHONE AND EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT FOR MALFUNCTION 
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
9 PURPOSE: VERIFY VOLTAGE SUPPLIED FROM EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT CONTROL CIRCUIT 
  • Measure the voltage at emergency call unit/telematics communication unit terminal 1W (wiring harness-side).
  • Is the voltage approx. 5.43 V?
 Yes Replace the emergency call unit/telematics communication unit and perform the repair completion verification 1.
(Refer to [EMERGENCY CALL UNIT REMOVAL/INSTALLATION] in service information.)
(Refer to TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION in service information.)
No Go to the next step.
10 PURPOSE: VERIFY VOLTAGE SUPPLIED AT CONTROL CIRCUIT CONTROLLED BY CONNECTIVITY MASTER UNIT (CMU) 
  • Measure the voltage at connectivity master unit (CMU) terminal 1G (wiring harness-side).
  • Is the voltage approx. 5.43 V?
 Yes Go to the next step.
No Replace the connectivity master unit (CMU) and perform the repair completion verification 1.
(Refer to CONNECTIVITY MASTER UNIT (CMU) REMOVAL/INSTALLATION in service information.)
11 PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT AND CONNECTIVITY MASTER UNIT (CMU) FOR MALFUNCTION 
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
12 PURPOSE: INSPECT EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT FOR MALFUNCTION DEPENDING ON REPEATABILITY 
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Clear the DTC recorded in the memory. (See CLEARING DTC .)
  • Replicate the vehicle conditions at the time the DTC was detected using the following procedure.
  • Perform the DTC inspection for the connectivity master unit (CMU). (See DTC INSPECTION .)
  • Is the same Pending DTC present?
 Yes Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
(See MALFUNCTION DIAGNOSIS FLOW [CONTROLLER AREA NETWORK (CAN)] .)
If the CAN communication is normal, replace the emergency call unit/telematics communication unit and perform the repair completion verification 1.
(Refer to [EMERGENCY CALL UNIT REMOVAL/INSTALLATION] in service information.)
(Refer to TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION in service information.)
No Go to repair completion verification 2.
Repair completion verification 1 PURPOSE: VERIFY THAT VEHICLE IS REPAIRED 
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Clear the DTC recorded in the memory. (See CLEARING DTC .)
  • Replicate the vehicle conditions at the time the DTC was detected using the following procedure.
  • Perform the DTC inspection for the connectivity master unit (CMU). (See DTC INSPECTION .)
  • Is the same Pending DTC present?
 Yes Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
(See MALFUNCTION DIAGNOSIS FLOW [CONTROLLER AREA NETWORK (CAN)] .)
If the CAN communication is normal, perform the diagnosis from Step 1.
No Go to the next step.
Repair completion verification 2 PURPOSE: VERIFY IF OTHER DTCs DISPLAYED 
  • Perform the DTC inspection. (See DTC INSPECTION .)
  • Are any other DTCs displayed?
 Yes Repair or replace the malfunctioning location according to the applicable DTC troubleshooting.
No DTC troubleshooting completed.
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