Usually when the D4 light flashes it means there is a tranny problem.
Transmission error
It means the car needs servicing.
The D4 light on a Honda Accord is the symbol for the 'check transmission' light. This light appears when the computer senses something wrong in the drivetrain. The computer should be diagnosed at a proper repair shop in order to source out what exactly is causing the problem.
A flashing D4 light on Honda Accords is commonly the result of a bad speed sensor. The speed sensor is located on the transmission and sends a signal to the speedometer and a signal telling the transmission when to shift.
There are lots of ways you could do it. The formula in A1 could be any of these: =D4*0.9 =D4*90% =D4-(D4*10%) =D4-(D4*0.1)
There is a problem with the A/T. Seek professional help.
There is a problem with the transmission and you need to get it to either honda or a mechanic.
It's the transmission computer.you need to replace it.
it means your motor is about too shut down and or is overheating.
Replace your AT Control Unit (Automatic Transmission Computer)
transmission trouble for sure