Wx Radar Display Question
Honeywell display on a commercial aircraft, R/T type unknown.
Does anyone here know exactly what weather radar malfunction is indicated when the radar, in the test mode, displays only the red bands (no yellow or green, but all 3 colors are shown in the sample panel on the lower left of the screen)? The radar seems a bit weak, but will display ground returns in WX and MAP mode. The auto-gain position (detent) displays nothing, but manual gain will produce a display of all 3 colors. No weather was available to test the unit.