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Diagnostic Procedure

DTC U2141:00 (AUDIO CONTROL UNIT (ACU)) DIAGNOSTIC PROCEDURE

Step Inspection Results Action
1 RELAUNCH AUDIO CONTROL UNIT (ACU) AND VERIFY REPEATABILITY 
  • Switch the ignition ON (engine off or on).
  • Perform the following operation to relaunch the audio control unit (ACU).
    • Switch the ignition OFF.
    • Remove all of the remote transmitters from the vehicle, lock all doors, and then wait for 10 min.
  • Switch the ignition ON (engine off or on).
  • Clear the DTC recorded in the memory. (Refer to the [CLEARING DTC ] in the appropriate service information)
  • Switch the ignition OFF, and then switch it ON (engine off or on) and wait for 30 s or more.
  • Perform the DTC inspection for the audio control unit (ACU). (Refer to the [DTC INSPECTION ] in the appropriate service information)
  • Is the same DTC displayed or does the same malfunction appear?
Yes Verify if the following DTCs are displayed at the same time.
  • U0162:00

    If U0162:00 is displayed 

  • Go to the next step.

    If they are not displayed 

  • Go to Step 7.
No Go to repair completion verification 2.
2 VERIFY CENTER DISPLAY POWER SUPPLY CIRCUIT (ACC) VOLTAGE 
  • Measure the voltage at the following terminals (vehicle wiring harness side).
    • Center display terminal 1G
  • Is the voltage B+?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC U0162:00 [AUDIO CONTROL UNIT (ACU)] .)
No Go to the next step.
3 INSPECT CENTER DISPLAY CONNECTOR FOR MALFUNCTION 
  • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION ] in the appropriate service information)
  • Are the connector and terminal normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
4 SHORT TO GROUND IN CENTER DISPLAY POWER SUPPLY CIRCUIT (ACC) 
  • Inspect the applicable circuit for a short to ground. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
5 SHORT TO POWER SUPPLY IN CENTER DISPLAY POWER SUPPLY CIRCUIT (ACC) 
  • Inspect the applicable circuit for a short to power supply. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
6 OPEN CIRCUIT IN CENTER DISPLAY POWER SUPPLY CIRCUIT (ACC) 
  • Inspect the applicable circuit for an open circuit. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
7 INSPECT COMMANDER SWITCH CONNECTOR FOR MALFUNCTION 
  • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION ] in the appropriate service information)
  • Are the connector and terminal normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
8 VERIFY COMMANDER SWITCH POWER SUPPLY CIRCUIT (B+) VOLTAGE 
  • Measure the voltage at the following terminals (vehicle wiring harness side).
    • Commander switch terminal A
  • Is the voltage B+?
Yes Go to Step 10.
No Go to the next step.
9 INSPECT COMMANDER SWITCH POWER SUPPLY CIRCUIT (B+) FOR SHORT TO GROUND AND OPEN CIRCUIT 
  • Inspect power supply circuit (B+) for short to ground and an open circuit. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Replace the commander switch and perform the repair completion verification. (Refer to the [COMMANDER SWITCH REMOVAL/INSTALLATION ] in the appropriate service information)
No Repair or replace the malfunctioning location and perform the repair completion verification.
10 INSPECT AUDIO CONTROL UNIT (ACU) CONNECTOR FOR MALFUNCTION 
  • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION ] in the appropriate service information)
  • Are the connector and terminal normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
11 VERIFY COMMANDER SWITCH POWER SUPPLY CIRCUIT (ACC) VOLTAGE 
  • Measure the voltage at the following terminals (vehicle wiring harness side).
    • Commander switch terminal D
  • Is the voltage B+?
Yes Go to Step 15.
No Go to the next step.
12 SHORT TO GROUND IN COMMANDER SWITCH POWER SUPPLY CIRCUIT (ACC) 
  • Inspect the applicable circuit for a short to ground. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
13 SHORT TO POWER SUPPLY IN COMMANDER SWITCH POWER SUPPLY CIRCUIT (ACC) 
  • Inspect the applicable circuit for a short to power supply. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
14 OPEN CIRCUIT IN COMMANDER SWITCH POWER SUPPLY CIRCUIT (ACC) 
  • Inspect the applicable circuit for an open circuit. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
15 SHORT TO GROUND IN COMMANDER SWITCH SIGNAL CIRCUIT 
  • Inspect the applicable circuit for a short to ground. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
16 SHORT TO POWER SUPPLY IN COMMANDER SWITCH SIGNAL CIRCUIT 
  • Inspect the applicable circuit for a short to power supply. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
17 OPEN CIRCUIT IN COMMANDER SWITCH SIGNAL CIRCUIT 
  • Inspect the applicable circuit for an open circuit. (Refer to the [CIRCUIT INSPECTION ] in the appropriate service information)
  • Is the circuit normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
18 INSPECT COMMANDER SWITCH FOR MALFUNCTION DEPENDING ON REPEATABILITY 
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Clear the DTC recorded in the memory. (Refer to the [CLEARING DTC ] in the appropriate service information)
  • Perform the DTC inspection for the audio control unit (ACU). (Refer to the [DTC INSPECTION ] in the appropriate service information)
  • Is the same Pending DTC present?
Yes Refer to the CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW to inspect for a CAN communication error.
(Refer to the [CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW ] in the appropriate service information)
If the CAN communication is normal, replace the commander switch and perform the repair completion verification.
(Refer to the [COMMANDER SWITCH REMOVAL/INSTALLATION ] in the appropriate service information)
No Go to repair completion verification 2.
Repair completion verification 1 VERIFY THAT VEHICLE IS REPAIRED 
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Clear the DTC recorded in the memory. (Refer to the [CLEARING DTC ] in the appropriate service information)
  • Perform the DTC inspection for the audio control unit (ACU). (Refer to the [DTC INSPECTION ] in the appropriate service information)
  • Is the same Pending DTC present?
Yes Refer to the CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW to inspect for a CAN communication error.
(Refer to the [CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW ] in the appropriate service information)
If the CAN communication is normal, perform the diagnosis from Step 1.
No Go to the next step.
Repair completion verification 2 VERIFY IF OTHER DTCs ARE DISPLAYED 
  • Perform the DTC inspection. (Refer to the [DTC INSPECTION ] in the appropriate service information)
  • Is a DTC displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
No DTC troubleshooting completed.