I have recently replaced the radiator, head gasket, distributor cap, rotor and plugs also the VSS about 6mo. ago. Now the D4 light flashes (check engine light doesn't come on) but it only flashes early in the morning as soon as its started then drive it about 6 miles to work. After I let it sit for about 3 hours it doesn't do it anymore for the rest of the day. Any ideas would be helpful. Thanks, Mike

 

D4 light flashing means the transmission control unit (TCU) is storing a fault code. See procedure in DIY forum for extracting codes and use this procedure, however codes will be flashed by D4 light instead of Check Engine Light.

Post back your code for help.

good luck

 

The D4 light has a steady continuous blink, gave up counting the blinks at 40. This morning when I first started it the light came on again and I drove it for about 1 mile then I turned it off let it sit a minute then started it right back up and the D4 light didn't flash anymore. It also feels like it shifts hard between 1st & 2nd gear when the light is flashing. It also has a slight miss, when first started the rpm's are at about 2000 then drop to about 750 after a couple of minutes. Could this be condensation on a connection somewhere from sitting overnight since the only time the light comes on is in the morning and if so where? Thanks for your time, Mike

 

You have to put the TCU in code output mode before the blinks can be read. The blinks that occur while driving w/ TCU in normal mode only serve as an indicator that a code has been stored and don't flash the code. Placing TCU in code output mode is done by shorting the service check connector under the glove box. It's a blue 2-wire connector and may be plugged into a plastic holder.

Do you understand the code blink sequence? Some blinks are long (1-2 secs) and some short (< 1sec). There are long pauses (2-3 secs) between successive different codes or a repeat of same sequence of codes. Code 14 is one long blink, short pause, and 4 short blinkes.

If you have TCU in code output mode and only continuous blinking w/ no pauses, the TCU is likely faulty. However, I would try a ECU/TCU reset. Pull BackUp fuse (7.5A) in underhood fuse box for 20 secs.

good luck

 

I'm getting a 7 on the D4 light (Shift Solenoid 'A' circuit open or shorted) and now the check engine light came on also and did 7 blinks (Throttle position sensor). The check engine light never came on before. Could it be coming on because of the D4 light and can you tell me where the Shift Solenoid 'A' circuit is? Thanks Again, Mike

 

You will need a shop manual to guide diagnostics. Suggest downloading the 94-97 Accord manual from Online Manuals links in DiY forum. These will guide your tests, but to summarize:

1) Check Solenoid A for correct resistance, open, or short. If it fails a new solenoid should be installed.
2) If solenoid A checks OK, then connectors, wiring, or ECU could be source of fault.

good luck

 

Thanks for all your help TexasHonda