Narrative:

Doing ILS approach runway xx at ZZZ at night at minimums conditions overcast at 200 ft. And 5 sm visibility between 600 and 400 feet the nose of the plane pushing down rapidly and we got 'terrain terrain' and pull up egpws warning.also at arriving at our diverted airport ZZZ1 at the moment to capture the ILS runway xy the localizer couldn't keep the needle centered; chasing left and right. We had to disconnect autopilot and fly aircraft manually. Weather was overcast at 600 ft.autopilot system malfunctioned.at ZZZ approach we have to execute an escape maneuver and go around and divert to alternate airport ZZZ1.as I mentioned above during both approaches we encounter autopilot; localizer and glide slope indication malfunctions; which is not safe under the weather conditions.

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Original NASA ASRS Text

Title: ERJ145 First Officer reported autopilot and navigation malfunctions during approach that resulted in a diversion.

Narrative: Doing ILS approach Runway XX at ZZZ at night at minimums conditions overcast at 200 ft. and 5 sm visibility between 600 and 400 feet the nose of the plane pushing down rapidly and we got 'Terrain Terrain' and Pull up EGPWS warning.Also at arriving at our diverted airport ZZZ1 at the moment to capture the ILS Runway XY the localizer couldn't keep the needle centered; chasing left and right. We had to disconnect autopilot and fly aircraft manually. Weather was overcast at 600 ft.Autopilot system malfunctioned.At ZZZ approach we have to execute an escape maneuver and go around and divert to alternate airport ZZZ1.As I mentioned above during both approaches we encounter autopilot; localizer and glide slope indication malfunctions; which is not safe under the weather conditions.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.