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Home >> Volvo >> 1994 >> 850 L5-2.4L VIN 55 B5254S >> Repair and Diagnosis >> Heating and Air Conditioning >> Testing and Inspection >> Component Tests and General Diagnostics >> Test Modes >> Test Mode 1
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Test Mode 1



Test Mode 1







Test mode 1 is used to read off stored DTCs for faults detected by the control unit diagnostic system.

- Ignition on.
- Press button, and keep it pressed for about 1 second.
- Read off LED flashes.

If LED does not light up when pressing button, perform fault tracing for communication with the control module.

If display reads 1-1-1, no DTC's are stored. If display shows a code other than 1-1-1:

- Display DTC's.
- Press button as above again to see if there is more than one DTC.
- Display all DTC's.

When the first DTC reappears, this means all DTC's have been displayed.

The delete the DTC's.

Perform fault tracing for the DTC's read off.
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