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.

DETERMINING SHORT TO GROUND LOCATION (CAN-BUS No. 8, US) - DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	INSPECT CAN LINE IN BODY CONTROL MODULE (BCM) FOR SHORT TO GROUND Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the connector 3 which has body control module (BCM) terminals 3V and 3U. Inspect for continuity at the following terminals: Between body control module (BCM) terminal 3V (wiring harness side) and body ground Between body control module (BCM) terminal 3U (wiring harness side) and body ground Is there continuity?	Yes	Go to the next step.
1		No	Replace the body control module (BCM) because there is a short to ground in the body control module (BCM). (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION (US) .)
2	INSPECT CAN LINE IN TELEMATICS COMMUNICATION UNIT FOR SHORT TO GROUND Disconnect the telematics communication unit connector. Inspect for continuity at the following terminals: Between telematics communication unit terminal 1Q (wiring harness side) and body ground Between telematics communication unit terminal 1S (wiring harness side) and body ground Is there continuity?	Yes	Repair or replace the wiring harness between the body control module (BCM) and telematics communication unit because the wiring harness is shorted to ground.
2		No	Replace the telematics communication unit because there is a short to ground in the telematics communication unit. (See TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION .)