Troubleshooting Diagnostic Procedure

U2145-02: (CMU) TROUBLESHOOTING DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	PURPOSE: VERIFY REMOTE TUNER (RT) OPERATION Output audio in the cabin using the audio amplifier. (Such as radio, navigation) Is audio output from the vehicle speakers?	Yes	Go to repair completion verification 1.
1		No	Go to the next step.
2	PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN BATTERY/LEAD-ACID BATTERY (WITH Mazda M Hybrid)/DC-DC CONVERTER (WITHOUT Mazda M Hybrid) AND REMOTE TUNER (RT) FOR MALFUNCTION Inspect the applicable circuit. (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Is the circuit normal?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
3	PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN REMOTE TUNER (RT) AND BODY GROUND FOR MALFUNCTION Inspect the applicable circuit. (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Is the circuit normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
4	PURPOSE: VERIFY MOST WAKE UP CIRCUIT VOLTAGE Measure the voltage at remote tuner (RT) terminal 1D (wiring harness-side). Is the voltage B+?	Yes	Go to Step 6.
4		No	Go to the next step.
5	PURPOSE: VERIFY OTHER CONNECTIVITY MASTER UNIT (CMU) DTCs Clear the DTC recorded in the memory. (See CLEARING DTC .) Perform the DTC inspection for the connectivity master unit (CMU). (See DTC INSPECTION .) Are any of the following DTCs displayed? U0186-02: U0186-08:	Yes	Repair or replace the malfunctioning location according to the applicable DTC troubleshooting. (See U0186-02: [CMU] .) (See U0186-08: [CMU] .)
5		No	Go to the next step.
6	PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN REMOTE TUNER (RT) AND AUDIO AMPLIFIER FOR MALFUNCTION Inspect the applicable circuit. (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Is the circuit normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
7	PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN REMOTE TUNER (RT) AND CONNECTIVITY MASTER UNIT (CMU) FOR MALFUNCTION Inspect the applicable circuit. (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Is the circuit normal?	Yes	Go to the next step.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
8	PURPOSE: INSPECT REMOTE TUNER (RT) FOR MALFUNCTION Inspect the applicable part. (Refer to REMOTE TUNER (RT) INSPECTION in service information.) Is the part normal?	Yes	Go to the next step.
8		No	Replace the remote tuner (RT) and perform the repair completion verification 1. (Refer to REMOTE TUNER (RT) REMOVAL/INSTALLATION in service information.)
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. Implement the repeatability verification procedure. (See REPEATABILITY VERIFICATION 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. If the malfunction recurs, replace the connectivity master unit (CMU), then go to the next step. (Refer to CONNECTIVITY MASTER UNIT (CMU) REMOVAL/INSTALLATION in service information.)
Repair completion verification 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.
Repair completion verification 2		No	DTC troubleshooting completed.