Relay circuit

The relay is not engaging.I swap Q5 and 6 from a next board but no change.If I ground pin 1 of Q5 it will engage.

Any suggestions?


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Are you sure that you're grounding the base of Q5 to get the relay to engage?

The base of Q5 has to go high for the relay to engage. I think it's Q4 that pulls it high.

If there is a really high value resistor near Q3 at the top of the board, check it. It will likely have to be removed to confirm it's within tolerance.