MFI #25, EZ #8 Load Signal Absent

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TQ. MFI#25, EZ#8 Load Signal Absent

Fault Message Conditions:

The fault message is logged if voltage is below 2.5 V for 400 ms.

The measurement is not carried out if fuel shut-off requirements are met - engine speed has been over 2200 rpm and then not dropped below 1100 rpm and the idle switch is on.

Causes of fault:




Break or grounding in the wiring between MFI#25 and DI#8.

Fault symptoms:

None apparent.

TQ1

Volvo ST, Test Box




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

-Connect the test box to 1CM and check the GND point in accordance with P3-P4.

-Continue with Checking the load signal to ICM TQ2.

TQ2

Checking The Load Signal To Ignition Control Module (1CM)

-Connect the control module to the test box.

-Install the fuse.




-Ignition on.

Connect a voltmeter between DI#8 and DI#20 (GND).

The voltmeter should read 200-500 mV.

If this value Is OK

Intermittent fault.

-Check the connections for loose contacts and intermittent grounding in accordance with NA3. Checking the Wiring

If the reading is approx. 7 V

-Check the wiring between the control modules for breaks.

If the reading is approx. 0 V

-Check the wiring's resistance to GND TQ3.

TQ3

Checking The Wiring's Resistance To GND




-Ignition off.

- Remove the fuse from the battery (in engine compartment (-90) or no.6 (91-).

-Disconnect both control modules.

Connect an ohmmeter between DI#8 and DI#20 (GND).

The ohmmeter should read infinite resistance.

If this value Is OK

-Try using a new control module.

If the reading is Incorrect

-Check the wiring between the control modules for grounding.