Determination 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.

CAUTION:

When disconnecting the connector, verify that there is no looseness, damage, deformation, corrosion, or poor connection of the connector terminals.
When inspecting the connector, touch it with a paper clip or similar thin pin without directly inserting a tester probe into the terminal.
Disconnect the negative battery cable before performing any work that requires handling of connectors.

DETERMINING SHORT TO POWER SUPPLY LOCATION (CAN-BUS No. 5, US) - DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	INSPECT CAN LINE BETWEEN BODY CONTROL MODULE (BCM) AND CONNECTOR C-06 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-06. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to Step 3.
1		No	Go to the next step.
2	INSPECT BODY CONTROL MODULE (BCM) FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector 2 which has body control module (BCM) terminals 2E and 2G. Connect the connector C-06. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G (wiring harness side). Is the voltage between 1.5-3.5 V?	Yes	Replace the body control module (BCM) because there is a short to the power supply in the body control module (BCM). (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION (US) .)
2		No	Repair or replace the wiring harness between the body control module (BCM) and connector C-06 because the wiring harness is shorted to the power supply.
3	INSPECT CAN LINE BETWEEN CONNECTOR C-47 AND CONNECTOR C-06 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-47. Connect the connector C-06. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to the next step.
3		No	Repair or replace the wiring harness between the connector C-47 and connector C-06 because the wiring harness is shorted to the power supply.
4	INSPECT CAN LINE BETWEEN PARKING ASSIST UNIT (OPTICAL)/360° VIEW MONITORING CAMERA UNIT AND CONNECTOR C-47 FOR SHORT TO POWER SUPPLY Measure the voltage at parking assist unit (optical)/360° view monitoring camera unit terminals 1C and 1A. Is the voltage between 1.5-3.5 V?	Yes	Go to Step 6.
4		No	Go to the next step.
5	INSPECT PARKING ASSIST UNIT (OPTICAL)/360° VIEW MONITORING CAMERA UNIT FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the parking assist unit (optical)/360° view monitoring camera unit connector. Connect the connector C-47. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Replace the parking assist unit (optical)/360° view monitoring camera unit because there is a short to the power supply in the parking assist unit (optical)/360° view monitoring camera unit. (See 360DEGREES VIEW MONITOR CONTROL MODULE REMOVAL/INSTALLATION (US) (See PARKING ASSIST UNIT (OPTICAL) REMOVAL/INSTALLATION (US) .)
5		No	Repair or replace the wiring harness between the parking assist unit (optical)/360° view monitoring camera unit and connector C-47 because the wiring harness is shorted to the power supply.
6	INSPECT JB No. 1 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-46. Connect the connector C-47. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to the next step.
6		No	Replace the JB No. 1 because there is a short to the power supply in the JB No. 1.
7	INSPECT CAN LINE BETWEEN CONNECTOR C-13 AND CONNECTOR C-46 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-13. Connect the connector C-46. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to the next step. (with driver monitoring (DM)) Go to Step 12. (without driver monitoring (DM))
7		No	Repair or replace the wiring harness between the connector C-13 and connector C-46 because the wiring harness is shorted to the power supply.
8	INSPECT CAN LINE BETWEEN CONNECTOR C-39 AND CONNECTOR C-13 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-39. Connect the connector C-13. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to the next step.
8		No	Repair or replace the wiring harness between the connector C-39 and connector C-13 because the wiring harness is shorted to the power supply.
9	INSPECT CAN LINE BETWEEN DRIVER MONITORING CAMERA UNIT AND CONNECTOR C-39 FOR SHORT TO POWER SUPPLY Measure the voltage at driver monitoring camera unit terminals 1F and 1E. Is the voltage between 1.5-3.5 V?	Yes	Go to Step 11.
9		No	Go to the next step.
10	INSPECT DRIVER MONITORING CAMERA UNIT FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the driver monitoring camera unit connector. Connect the connector C-39. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Replace the driver monitoring camera unit because there is a short to the power supply in the driver monitoring camera unit. (See DRIVER MONITORING CAMERA UNIT REMOVAL/INSTALLATION (US) .)
10		No	Repair or replace the wiring harness between the driver monitoring camera unit and connector C-39 because the wiring harness is shorted to the power supply.
11	INSPECT CAN LINE BETWEEN CONNECTOR C-16 AND CONNECTOR C-39 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-16. Connect the connector C-39. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to Step 13.
11		No	Repair or replace the wiring harness between the connector C-16 and connector C-39 because the wiring harness is shorted to the power supply.
12	INSPECT CAN LINE BETWEEN CONNECTOR C-16 AND CONNECTOR C-13 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-16. Connect the connector C-13. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to the next step.
12		No	Repair or replace the wiring harness between the connector C-16 and connector C-13 because the wiring harness is shorted to the power supply.
13	INSPECT CAN LINE BETWEEN CONNECTOR C-27 AND CONNECTOR C-16 FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector C-27. Connect the connector C-16. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Go to the next step.
13		No	Repair or replace the wiring harness between the connector C-27 and connector C-16 because the wiring harness is shorted to the power supply.
14	INSPECT DRIVER FORWARD SENSING CAMERA (FSC) FOR SHORT TO POWER SUPPLY Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the forward sensing camera (FSC) connector. Connect the connector C-27. Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off). Measure the voltage at body control module (BCM) terminals 2E and 2G. Is the voltage between 1.5-3.5 V?	Yes	Replace the forward sensing camera (FSC) because there is a short to the power supply in the forward sensing camera (FSC). (See FORWARD SENSING CAMERA (FSC) REMOVAL/INSTALLATION .)
14		No	Repair or replace the wiring harness between the forward sensing camera (FSC) and connector C-27 because the wiring harness is shorted to the power supply.