Possible cause

• Connector terminal disconnection, poor contact, damage, deformation, corrosion
• Open circuit in wiring harness between connector C-64 and connector C-14
• Open circuit in wiring harness between connector C-14 and connector C-71
• Open circuit in wiring harness between connector C-71 and rear body control module (RBCM)
• Connector C-64 malfunction
• Connector C-14 malfunction
• Connector C-71 malfunction
• CAN circuit in rear body control module (RBCM) malfunction

System wiring diagram

Fig 1: Climate Control Unit Communication Diagram

Courtesy of MAZDA MOTORS CORP.