Mitsubishi: ODBII and ABS

Normally OBDII is only in the central computer on any vehicle. By that
I mean that you talk to the central ECU (ETAC), and it talks to the
other ECU's. Under most conditions you can not talk directly to , for
example, the ECU computer module for the ABS.
All the scan tools talk to the main ECU (ETAC) and only the main ECU,
and through that you talk to the other units.

The main ECU should provide you with all the error codes for the ABS
module.

In Mitsubishi's world, of late, the various ECU's are tired together,
and talk to each other over what is call "SWS" or simplified wire
system. One wire is designated as a communication line, common to all
ECU modules.

Each ECU can talk to another ECU, but usually only to the ETAC (server) ECU.

Mitsubishi does have a device similar to a scan tool, that plugs into
the SWS system (separate connector under the dash) and allows trouble
shooting over the communication wire. This tool allows the user to
control the other functions of the other ECU's.

If your into electronics, think of it as a "sniffer". A device that
monitors network communications.

To date I have found nothing outside of Mitsu., that supports
communication on this data link.

New cars soon will have standardized on the, "CAN" network. Thats,
Control Area Network.
You can thank (or curse) the US government, for forcing all vehicle
manufacturers to standardize on a single network, for vehicle
communications.

There are currently "sniffers" available for the "CAN" network, but
other than Mitsu's version, nothing for the current, or even your,
version of the Eclipse.

Mitsu uses their version of a "scan tool" (MB991502) for monitoring the
ABS codes. These are present at the standard OBDII connector. They
also use a tool (MB991529) for checking ABS codes. This tool appears to
do nothing more than ground pin one of the OBDII connector, so that you
can read the ABS codes from the flashing "ABS warning light".

The manually says "Use special tool MB991529 to ground number 1 terminal
of the data link connector".
It goes on to say, "Read out a diagnostic trouble code by observing how
the warning light flashes".

I've left out a few steps, so it won't work if you try it, this post is
already getting to long.

Error codes go from "11" to "63"
The manual also says " Tool not necessary if scan tool is available".

Good Luck




John A wrote: