I just bought a used 2000 Civic EX last Monday. Drove almost 200 miles with it so far; however, this morning my check engine light came on and my D4 light started flashing.

I decoded the check engine light with the help of the ECU sticky and got a sequence of "!....!.!.!.!.!.!.!....!.!.!.!.!.!.!....!,etc) which is code 16 if I decoded it correctly.

I decoded the D4 light and got 15 and 41 codes. I am not sure if the D4 codes mean the same as the ECU ones from the check engine light, since they are coming from the tranny. Could anyone shed some light on the D4 flashing?

Thanks,
Sean

 

I dont know what a D4 light is because i run OBD1 but from your ecu codes it looks like your throwing 16 and 6

6 ECT - water temperature sensor

16 Fuel injectors


Code 15 and 41 are:

15 Ignition output signal

41 Primary oxygen sensor heater


Looks like the car has alot of problems, i would try to return it.

Edit: Your in Cali, take it to get smogged within 30 days of purchase and if you dont pass take it back to the previous owner because its there responciblity to make it pass smog so theyll have to fix everything.

 

Actually, I just checked again and it looks like its a code 7. I was interpreting the codes by checking the time between flashes since each flash lasted the same duration, and I counted the long pause between the 7 flashes as a value of 10; however, it was actually the pause between each ECU code. I assume each flash represented a one since they are only about half second flashes. I believe a '10' flash would be longer than that. In this case, it would mean throttle position sensor. Is this major?

The D4 light is the D4 shift indicater. I am still stumped on this since I havn't found much information on it on the internet. I read that on other Hondas, the D4 codes are coming straight from the tranny, but I havn't found what they would mean.

Sean

 

Is it possible that the D4 light could be flashing out extra data that relates to the ECU code? They both went off at the same time, as far as I could tell.

Sean

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by aglswapbuffers &raquo;</TD></TR><TR><TD CLASS="quote">
I decoded the D4 light and got 15 and 41 codes. </TD></TR></TABLE>
15=problem with the lock up clutch
41=problem with the shift control system
I've never seen either of these codes on a Civic.

 

When I was driving to work today, the D4 light actually stopped flashing; however, the CEL is still on.

I have an automatic transmission. Would those error codes still apply? Those errors don't seem too good. Should I worry about it providing the D4 light doesn't come back?