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MFI# 35 No Power From the Ignition Switch



TS. MFI #35

MFI#35 No power supply from the ignition switch

Fault Message Conditions:

If the 1CM and the power stage are connected to the ST the fault message will be logged if the voltages to DI#6, power stage #4 and MFI#35 differ.

Causes of fault:




Break in the wiring between MFI#35 and the ignition switch.

Fault symptoms:

The engine will not start.

No symptoms if the break is intermittent.

TS1

Volvo ST, Test Box




-Disconnect the ST in accordance with QA2. Connecting The Volvo Scan Tool (ST)

-Connect the test box to MFI and check GND points.

-Continue with Checking the power supply TS2.

TS2

Checking The Power Supply




-Connect the control module to the test box.

-Install the fuse.

-Ignition on.

Connect a voltmeter between MFI#35 and MFI#5 (GND).

The voltmeter should read battery voltage.




-Check that the voltmeter reads battery voltage when the starter motor and the engine are running.

If both values are OK

Intermittent fault.

-Check the connections between MFI#35 and the ignition switch for loose contacts.

If the reading is Incorrect

-Check the wiring between MFI#35 and the ignition switch for breaks in accordance with NA2. Checking the Wiring