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Home >> Mazda >> 2012 >> 5 L4-2.5L >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> U Code Charts >> U0001 >> Multiplex Communication System
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Multiplex Communication System





DTC U0001:88, U0073, U0073:00 [MULTIPLEX COMMUNICATION SYSTEM]

CAUTION:
- First perform the following malfunction diagnosis according to the Initial Inspection and Diagnostic Overview troubleshooting procedure.

Detection condition

- CAN system related wiring harness malfunction
- CAN system-related module malfunction

Possible cause

- Connector malfunction
- Open or short circuit in wiring harness
- PCM malfunction
- TCM malfunction (ATX)
- EHPAS control module malfunction
- DSC HU / CU malfunction
- BCM malfunction
- SAS control module malfunction
- Instrument cluster malfunction

System wiring diagram





Diagnostic Procedure

CAUTION:
- When disconnecting the connector, verify that there is no looseness, damage, deformation, corrosion, or poor connection of the connector terminals.
- When inspecting the DLC-2, touch it with a paper clip or similar thin pin without directly inserting a tester into the terminals.









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