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TC. MFI #4 No Power Supply From Battery



TC. MFI#4

MFI#4 No power supply from battery




Fault message conditions:
The fault message is posted if voltage is below 1 V.

Fault causes:
Break in the wiring between MFI#4 and the battery.

Fault symptoms:
The OBD system is not working. The engine will not start if the fault exists.

TC1




Volvo ST, Test box
- Disconnect the ST in accordance with QA2. QA. Connecting The Volvo Scan Tool (ST)
- Connect the test box to MFI and check the GND points in accordance with P1-P2. P. Test Box, Signal Description
^ Continue with Checking the power supply TC2.

TC2




Checking the power supply
- Connect the control module to the test box.
- Install the fuse.
- Ignition on.
Connect a voltmeter between MFI#4 and MFI#5.
The voltmeter should read battery voltage.

If this value is OK
Intermittent fault.
^ Check the wiring between MFI#4 and the battery for loose contacts in accordance with NA5. NA. Checking the Wiring

If the reading Is incorrect
^ check the wiring between MFI#4 and the battery for breaks in accordance with NA2. NA. Checking the Wiring