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Check Code Inspection

CHECK CODE 01 INSPECTION REFERENCE

Check code 01	CAN system
INSPECTION CONDITION	DISPLAY	ACTION
Select the check code 01	Courtesy of MAZDA MOTORS CORP.	CAN system of information display is normal.
Select the check code 01	Courtesy of MAZDA MOTORS CORP.	CAN system communication error. (DTC U2516) (See DTC TABLE[MULTIPLEX COMMUNICATION SYSTEM] )

CHECK CODE 02 INSPECTION REFERENCE

Check code 02	Communication status to audio unit Communication status to climate control unit Communication status to instrument cluster
INSPECTION CONDITION	DISPLAY		ACTION
Select the check code 02. (The diagnostic results will be displayed once each in the order of audio unit, heater control unit, and instrument cluster.)	Courtesy of MAZDA MOTORS CORP.		All communications are normal.
	Audio unit	Courtesy of MAZDA MOTORS CORP.	Communication to audio unit is normal.
		Courtesy of MAZDA MOTORS CORP.	Communication error to audio unit. (DTC U0184) (See DTC TABLE[MULTIPLEX COMMUNICATION SYSTEM] )
		Courtesy of MAZDA MOTORS CORP.	Vehicle without audio unit.
	Climate control unit	Courtesy of MAZDA MOTORS CORP.	Communication to climate control unit is normal.
		Courtesy of MAZDA MOTORS CORP.	Communication error to climate control unit. (DTC U0166) (See DTC TABLE[MULTIPLEX COMMUNICATION SYSTEM] )
		Courtesy of MAZDA MOTORS CORP.	Vehicle without climate control unit.
	Instrument cluster	Courtesy of MAZDA MOTORS CORP.	Communication to instrument cluster is normal.
	Instrument cluster	Courtesy of MAZDA MOTORS CORP.	Communication error to instrument cluster. (DTC U0181) (See DTC TABLE[MULTIPLEX COMMUNICATION SYSTEM] )

CHECK CODE 04 INSPECTION REFERENCE

Check code 04	TNS relay ON/OFF signal
STEP	INSPECTION CONDITION	DISPLAY	ACTION
1	Turn the headlight switch to the TNS position. (TNS relay ON)	Courtesy of MAZDA MOTORS CORP.	Go to the next step.
1		Courtesy of MAZDA MOTORS CORP.	Verify that the voltage of information display terminal C is B+ . If the voltage is as specified, replace the information display. If the voltage is not as specified, inspect the following parts: TNS relay Wiring harness (Battery-TNS relay-information display)
2	Turn the headlight switch off. (TNS relay OFF)	Courtesy of MAZDA MOTORS CORP.	Verify that the voltage of the information display terminal C is 1.0 V or less . If the voltage is as specified, replace the information display. If the voltage is not as specified, inspect the following parts: TNS relay Wiring harness (TNS relay-information display)
2	Turn the headlight switch off. (TNS relay OFF)	Courtesy of MAZDA MOTORS CORP.	Input signal to the information display is normal.

LCD REFERENCE

Check code -	LCD
DISPLAY	ACTION
Courtesy of MAZDA MOTORS CORP.	All segments and dots illuminated.	LCD is normal.
Courtesy of MAZDA MOTORS CORP.	Except above	Replace the information display.