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You didn't give any details on what car your talking about but in general terms a blinking "D" light indicates that there is a problem with the transmission. This may be something mechanical such as a shift solenoid or possibly some electrical such as a transmission speed sensor. This may also indicate that the transmission fluid may be low as well.
You didn't give any details on what car your talking about but in general terms a blinking "D" light indicates that there is a problem with the transmission. This may be something mechanical such as a shift solenoid or possibly some electrical such as a transmission speed sensor. This may also indicate that the transmission fluid may be low as well.