According to Le Ferrovie Coloniali Italiane, there were four types of passenger cars.  One of Saloncino de Governatore (ST^V_Z) was built in 1914.  I have no pictures of it.  Six mixed 1st class and 2nd class (ABT^V_Z) were built. They held 12 first class and 36 second class passengers.  Six 3rd class (CT^V_Z) were built.  They held 44 passengers.  There were four (DT^V_Z) baggage cars built.  The last three were built in 1913.  All were 11.924 meters long.  This gives a total of seventeen.  The "Short Description of the System" shows 19 passenger cars.

Photo courtesy Italian Institute of Agronomy.
This picture shows a consist of DT^V_Z,  ABT^V_Z, and CT^V_Z.  I don't know if the Eritrean Railway carried on the Italian designation after 1941.  Also, I do not know the source of the extra two passenger cars.

Eric Lafforgue's picture shows one of the Baggage cars have been rebuilt.  Frederick C. Gamst shows a train with a Baggage Car, a Mixed Class Car and three Passenger Cars at Ela Bared.
 

Photo courtesy of Rick Baxter

Far Wheels says that there was little difference between the 2nd and 3rd class coaches on the inside.  I don't know which this is
.
Photo courtesy of Rick Baxter

Photo courtesy of Rick Baxter

The only way I know how to tell is the markings on the outside end.  One wonders what the class of the top coach is.  It does not have the plate.  Here one can see the Logo on the side of the car.  There is a third item that, as of yet, I have not been able to identify.  It looks like it may be a stylized 'V'.  The first character is clearly a Ge'ez character, which may be the first character in Eritrea.  The last character looks like a stylized 'Ry.'  I don't remember it on a list of Ge'ez characters.   For those not in the know, Ge'ez was the ancient language of this area.  It is the written language of Amharic, Tigranya, and others.

Photo courtesy of Rick Baxter

Jane Baxter is with one of the flat cars which have been converted for passenger use.

Photo courtesy of Rick Baxter
Riding on a passenger train with manual breaking must be a thrilling experience.  When it runs on some of the steepest mainline grades in the world, it must be breath taking.  When the brakeman is in his 70s and looks like a wind would blow him away, it must be heart stopping.  I am surprised Rick made it back!