Diagnostic Procedure

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC B1A89:2B (CONNECTIVITY MASTER UNIT) DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	VERIFY OTHER CONNECTIVITY MASTER UNIT (CMU) DTCs Clear the DTC recorded in the memory. (Refer to the [CLEARING DTC] in the appropriate service information) Perform the DTC inspection for the connectivity master unit (CMU). (Refer to the [DTC INSPECTION] in the appropriate service information) Are any of the following DTCs displayed? U0186:02 U0186:08 U2145:02 U2145:08	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [CONNECTIVITY MASTER UNIT (US)] .)
1		No	Go to the next step.
2	VERIFY IF Sirius XM SATELLITE RADIO CAN BE RECEIVED Switch the ignition ON (engine off or on) and display the Sirius SM satellite radio screen on the center display. Can the Sirius XM satellite radio be received?	Yes	Verify that the repairs have been completed.
2		No	Go to the next step.
3	VERIFY SIGNAL STRENGTH OF Sirius XM SATELLITE RADIO Display the [SiriusXM Authentication] using the diagnostic assist function. (See DIAGNOSTIC ASSIST FUNCTION [CONNECTIVITY MASTER UNIT (US)] .) Does the signal display indicate [NO SIGNAL]?	Yes	Go to the next step.
3		No	Verify that the repairs have been completed.
4	INSPECT Sirius XM SATELLITE RADIO ANTENNA AMPLIFIER 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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT REMOTE TUNER (RT) 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.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT Sirius XM SATELLITE RADIO ANTENNA AMPLIFIER SIGNAL CIRCUIT FOR SHORT TO GROUND 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.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification. (Refer to the [ANTENNA FEEDER NO. 1 REMOVAL/INSTALLATION] in the appropriate service information) (4SD) (Refer to the [ANTENNA FEEDER NO. 2 REMOVAL/INSTALLATION] in the appropriate service information) (5HB/WGN)
7	INSPECT Sirius XM SATELLITE RADIO ANTENNA AMPLIFIER SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 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.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification. (Refer to the [ANTENNA FEEDER NO. 1 REMOVAL/INSTALLATION] in the appropriate service information) (4SD) (Refer to the [ANTENNA FEEDER NO. 2 REMOVAL/INSTALLATION] in the appropriate service information) (5HB/WGN)
8	DETERMINE MALFUNCTIONING LOCATION NOTE: If there is no response, move the vehicle outside (in environment where radio signal is not interrupted or obstructed) and verify the display again. Replace the Sirius XM satellite radio antenna amplifier. (Refer to the [ANTENNA FEEDER NO. 1 REMOVAL/INSTALLATION] in the appropriate service information) (4SD) (Refer to the [ANTENNA FEEDER NO. 2 REMOVAL/INSTALLATION] in the appropriate service information) (5HB/WGN) Display the [SiriusXM Authentication] using the diagnostic assist function. (See DIAGNOSTIC ASSIST FUNCTION [CONNECTIVITY MASTER UNIT (US)] .) Does the signal display indicate [GOOD] or [MARGINAL]?	Yes	Verify that the repairs have been completed.
8		No	Put back the Sirius XM satellite radio antenna amplifier that was replaced, replace the remote tuner (RT), and perform the repair completion verification. (Refer to the [ANTENNA FEEDER NO. 1 REMOVAL/INSTALLATION] in the appropriate service information) (4SD) (Refer to the [ANTENNA FEEDER NO. 2 REMOVAL/INSTALLATION] in the appropriate service information) (5HB/WGN) (Refer to the [REMOTE TUNER (RT) REMOVAL/INSTALLATION] in the appropriate service information)
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 connectivity master unit (CMU). (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. If the malfunction recurs, replace the remote tuner (RT), then go to the next step. (Refer to the [REMOTE TUNER (RT) REMOVAL/INSTALLATION] in the appropriate service information)
Repair completion verification 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.
Repair completion verification 2		No	DTC troubleshooting completed.