Br 101 Expert Multi Loco Power Output

I found that locomotives on IC 1279 in Kassel - Würzburg route was a push-pull(as known as sandwich config). The MTD display shows the line voltage and master circiut breaker status max up to 4 locos.

So I tried to put 4 locos together, 1(Lead driving)-2-3-4 and follow steps:
1. As soon as all locos connect together, shut down all locos completely, includes the battery and set the multiple control selector to "ZMS". (I choose ZMS because this article: http://www.moebahn.de/t9363f123-Wendezugsteuerung-Wer-kann-mit-wem.html)
2. Turn on battery of loco #4, wait for sys self test complete. Put reverser to N, raise the pantograph, close the master circuit breaker. Put reverser to 0(or X/OFF shows on game overlay).
3. Repeat step 2 on loco #3, #2 and #1.
4. 4 locos BR101 multiple unit complete.

When I finish step 2 on loco #1, it does shows all 4 locos on MTD. And then continue finish all other settings. I give full power, but only the front 3 locos have tractions. And when I set full elec brake, all locos output max of 150kN brake effort. Elec brakes are normal, a loco max can supply 150kN braking. But why forward traction only output on 3 locos, what was limited that?

And seems "ZDS BR120" mode can only support 2 locos wheather all put them together or separately?

 

Correct ZDS BR120 is for Push Pull so maximum of 2 locs in lead and behind with coaches in between or Sandwich and it im right ZMS is for double/triple traction so 2/3/4 locos behind each other but more than 2 locos never used in IC/EC traffic maybe in a special situations but not in normal service. And ZWS "Zeitmultiplexe Wendezugsteuerung" is for IC coaches or with the 143/146 with Dosto coaches. And also an older system KWS is for n-wagen with locos with TB0

cwf.green Can you correct me if im wrong Please?