"Roy and Rosa" <rbeaty@grandecom.net> wrote in message
news:10qq8g9qp1pdb0c@corp.supernews.com...
> Yes. I have 12 volts to ground on hot side of fuse and no volts on load
> side. ( with fuse pulled)
> volts on both sides with fuse in.
> I have checked all the simple stuff. I'm into the hard stuff now.
> thats why I need a diagram or pinout at ecu.
>
> should ecu flash anything on powerup ,or ignition on, even if ecu is
> good?
> see earlier post "89 civic HB, no spark, not main relay or ignitor"
> Roy
>
I don't have the pinout or wiring diagram, but I have a book on checking
codes for 1983-1995 import cars. (It was part of a $35 kit from Checker
Auto, which turns out to be a $30 book, a two dollar generic jumper tool and
a three dollar Toyota jumper tool.)

For the '89 Civic, it confirms you don't need a tool or to do anything
special to see the codes. It says: "Access ECU (located on passenger side
floorboard) by pulling back the carpet. Turn ignition on and observe LED on
ECU for codes. Codes blinked out by LED are separated by two second pause,
then repeated. For example, 2 blinks - two second pause - 2 blinks = code
2." The diagram shows the ECU at the passenger's toes, but it sounds like
you've already gotten that far. When you do get error codes, they are
cleared by removing fuse 30 for 10 seconds.

However, the chart doesn't list a code for "no problem - working okay." I
suppose you could unplug the crank angle sensor connector at the distributor
and you should see a code 8, but if you still don't what does that tell you?

The next thing might be to check each pin on the ECU connector for voltage
with the ignition off, and verify that it goes away when the fuse is pulled.
If you do have that, there should be at least one solid black wire on the
connector (the same connector if there is more than one) and it should ohm
to ground. It's really unusual for an ECU to fail like that unless it got
wet or voltage spiked somehow.

One more thing - are you sure that's the right fuse? 15 amps sounds like a
pretty hefty fuse for the ECU. In the '90-93 Accord it is a 7.5 amp fuse. (I
have a book for those models - in those models the power wire is a
white/yellow wire on pin D1; pin 1 of connector D.) The code book suggests
it is fuse #30 in yours.

Mike