Q: I replaced my DCM unit but problem is only solved with Car in on position

Diagnosing this issue requires the Factory Service Manual and the wiring diagram at minimum. If the turn signal circuit is not working when the vehicle is on, and it is wired through this DCM, that circuit is simple enough that tracing that might lead you to the global issue, that is the reason that none of the other DCM devices are working when the car is running. But, even tracing the turn signal circuit is going to require the wiring diagram. If you don’t want to obtain the wiring diagrams, please simply request an electrical component diagnostic and the responding certified mechanic will resolve this, right at your location. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.