Yes, but do you really need one.
My son has the exact same car, and we've been down this road.
Caution, follow these instructions at your own risk, they may damage your
car if you do it incorrectly.
You can get the codes out of the ECU by attaching a voltmeter to pin 1 of
the OBD output connector, and grounding pin 12 (ignition key in "RUN"
postion). The ECU then outputs a series of pulses, that indicate the error
code. The connector is located by the left kick panel, by the fuse block
(may have a black protective cover on it). As the connector pins face you,
with the keyway on the top row of pins, pin one is on the top row, extreme
right. Pin 12 is on the lower row, extreme left. Be aware that if the
output is a constant high signal, the manual says to replace the ECU. But
at this point you'd already guessed this, because the care won't run. And
that's a whole nother issue.
Under this condition, some (most) ECU's can be repaired (done it three times
already on three different ECU's).
You should be aware that ECU's of this vintage (in Mitsu world) are world
renowned for there failures. If yours is still working, I would suggest
that you get it upgraded ASAP. If you know your way around a soldering
iron, the repair will be less than $5.00,US, including parts
Any shop manual for this car will have the instructions and the codes listed
in it. If you don't have one (or can't borrow one) check with your local
library. Even with a scan tool, you'll need the manual to decode the
OBD for this vintage is not industry standard, and every manufacturer had a
different set of codes, and ways of getting at them.
By the way, what is your problem?
Oh and another thing, there are after market data loggers available for this
ECU, if your interested.
The problem is thatthe car has started without a problem since new and
the other day it would not start. I did some diagnostics on the fuel
delivery system, and I was able to manually power up the fuel pump,
but it would not pump via turning on the ignition key. So... I
checked the resistance on the EFI control relay (or whatever it is
called) and some of the readings were off a bit. I purchased a new
relay and it did not correct the problem. The car still cranks but
does not start.
As soon as it stops raining here, I plan to check out the coil and
spark generation and do more testing on the fuel pump. It just seemed
strange that the car would run fine one day and not start (but will
crank) the next. It seems as though it might be electrical. I do
have the service manual and I did find the codes (by pulse) so I plan
to go out and purchase an analog voltmeter to decipher these pulses.
If the ECU turns out to be bad, where may I ask, did you find info on
how to repair one?
Thanks for the info. Any suggestions would be appreciated.
Tonight I checked for spark at the plugs and there was none. I
checked out the coil and the primary, secondary, and insulation
resistance was fine. While I was in there, I went ahead and replaced
the cap and rotor because they were worn.
I then tried to start the car - it cranked but did not start or even
Then I went to the ECM to see if I could get any diagnostic codes from
it. I connected an analog voltmeter to pins 1 and 12 and turned the
ignition to on and I got no reading at all. I thought that maybe the
voltmeter might not be working so I tested it on a battery and it read
12.7 volts. I tried again, still nothing. I tried a digital
voltmeter on the lowest scale. I got a less than 1v reading with no
pulsing of any kind.
According to the book, when the ECM is bad it is supposed to remain at
12v. When the ECM is functioning properly, it should pulse evenly on
I then checked all fuse links and fuses under the hood and they all
Boy, your description of the problem sure points to the ECu. That is the
exact way my sons car went, twice.
I say twice, cuase we went to the auto wrecker, got a salvaged module,
didn't get it upgraded, and it failed the same way three months later.
After I bought the third module, I compared it to the failed modules, found
the problem, then repaired all three before installing one in my sons car.
The problem is the electrolytic capacitors. There are three or four of
them. They tend to fail and leak electrolyte onto the PCB. The fix (if
your module is still working), is to just replace them. If your module has
failed, usually just replacing the caps, and repairing any corroded traces,
is all that is needed. After the repair, wash the board, and reseal it with
a conformal coating (clear lacquer spray paint works OK)
I'll be damned if I can find that web site that gives the instructions on
how to do it. It was a good site, they even had pictures. Someone on this
news group could probably help here.
One of the modules my son had (the last one) had a black hole blown into the
PCB by the exploding cap. I cleaned out the carbon, replaced the traces
with wires then sealed the PCB with conformal coating, that was last year,
still no problems.
I will take it (the ECM) out in the morning and examine it. If anyone
knows of the web site please post the URL here. If I find it via a
search engine I will also post it.
On Sun, 06 Jun 2004 02:44:34 GMT, "Nirodac"