ADV7390 H/V sync outputs while generating internal test signals

I am using ADV7390 to generate SD color bars, and using CVBS output.  Everything is working fine in both NTSC and PAL.  However, while generating test signals, no /HSYNC and /VSYNC signals appear at the respective pins.  I have configured these two pins as outputs, following information in Tables 54, 55, and 56 in the datasheet Rev. J.  Specifically:

Subaddress 0x02, bit 6 = 1

Subaddress 0x02, bit 7 = 0

There is no signal output.  Does the ADV7390 not output sync signals while using its own internal test signal generator?

Thanks!