Backup Power Supply Inspection
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.
- Disconnect the negative battery terminal.
- Remove the backup power supply. (See BACKUP POWER SUPPLY REMOVAL/INSTALLATION (US) .)
- Connect the backup power supply connector.
- Connect the negative battery terminal.
- Verify that the voltages of each of the terminals are as indicated in the terminal voltage table (reference).
- If the voltage is not as specified in the terminal voltage table (reference), inspect the parts under Inspection item(s) and related wiring harnesses.
- If the system does not operate normally even though the inspection items are normal, replace the backup power supply. (See BACKUP POWER SUPPLY REMOVAL/INSTALLATION (US) .)
- If the voltage is not as specified in the terminal voltage table (reference), inspect the parts under Inspection item(s) and related wiring harnesses.
Terminal Voltage Table (Reference)
| Terminal | Signal name | Connected to | Test condition | Voltage (V) | Inspection item |
|---|---|---|---|---|---|
| A | Power supply | Electrical supply unit (ESU) | Under any condition | B+ |
|
| B | Power supply | Electrical supply unit (ESU) | Under any condition | B+ |
|
| C | Power supply (IG1) | F48 7.5A fuse | Ignition switched ON (engine off or on) | B+ |
|
| Ignition switched OFF (LOCK) | 1.0 or less | ||||
| D | 78 | - | - | - | - |
| E | - | - | - | - | - |
| F | - | - | - | - | - |
| G | - | - | - | - | - |
| H | - | - | - | - | - |
| I | GND | Body ground | Under any condition | Approx. 0 |
|
| J | Power supply | Electrical supply unit (ESU) | Under any condition | B+ |
|