Hi Wolfgang, ich habe hier auch einen kleinen Lehrgang zum f355F1 gemacht, allerdings eher hydraulischer Art, vielleicht könnten wir uns mal zwecks einem Brainstormig zusammen telfonieren? [email protected] 0351-2066312 Liebe Grüsse nach München Carsten
Hi, Wolfgang72 Could you please give me advice. What voltage comes out of the TCU to solenoids EV1-EV5? My F355 won't engage in 4th gear. I checked all the wires and solenoids. As I understand it, I have a problem with the signal from the TCU to the solenoid EV2. Seems that is not enough voltageand it does not retract the shaft. If I swap the connector from EV1 to EV2. Then it easily engages 4th gear. I measured the voltage at the output from the TCU when shifting gears and it is about 4V on solenoids EV1 and EV2 and about 12V on the rest (EV3-EV5) Thank you!
EV2 to EV5 are On/Off solenoids. That's fine as they simply select the shift track. The control arm moves without any resistance here and so there is nothing to take care of. They operate on 12V (on) and 0V (off). EV1 and EV2 are PPV solenoids. When engaging gear, the TCU uses the control arm to move the shift collar into the direction of the target gear until the sync disc touches. Then it gradually increases force until the disc is up to speed. Finally, it engages gear (https://www.ferrarichat.com/forum/posts/148238381/). These solenoids are controlled by current, which is set by using a (12V) PWM. The 4V you see are likely a result of this PWM. You can test your solenoids by measuring their resistance. Simply compare the readings among the solenoids of the same type. In Theory, you can test a solenoid by briefly ("sub-second") applying 12V. But I do not recommend this, as there is the risk to misalign the shift linkage.
