6643jasper

Just recently acquired a 2000 civic ex with an auto. Got it cheap due to the d4 light flashing. Now I did some research online and seemed like a simple fix. Let me say it is not. I have swapped the linear shift solenoid out with a known good part. Ohmed the wiring and found it to be out of spec so ran new wires. Checked for voltage coming into PCM and verified 12 volts. Ohmed the PCM ground which are good. I have swapped PCM for a know good part. And nothing works. As soon as I turn the key on d4 light flashes. Car doesn't even have to be running. If you do drive it the trans shifts hard and seems to be taking off in od. If you manually shift it seems fine. What I have noticed is there is no reference voltage at the shift solenoid. Does anyone have any suggestions??? I think I have told you guys everything.

TIMMY4TOES

Did you check the oil to make sure it is nice and pink? Also, have you tried to reset code and then see if car works fine momentarily?


If it acts like a duck and talk like a duck, your tranny is more than likely done.


GLWFix

TIMMY4TOES

how many miles are on car as well?

6643jasper

Car has 177000 miles. The previous owner give me a receipt for the transmission purchased in the last couple thousand miles. It was bought at a honda dealer and put in on the side by a honda tech. Failed to mention sorry about that.

If I clear the code it comes back immediately without even driving the car.

6643jasper

Update.

I have found that the pcm doesn't give the reference voltage to the linear solenoid of 1 volt as it should. I borrowed a friends 99 civic and his car references 1 volt and drops to a half volt. The car I'm working on just goes straight to half volt. Where could I be losing that input voltage.