charging

Sorry, I do not know anything about the Mobilette.

Error 17 - Capacitor bank charging to slow - some things for you to check.

• Check that S10 on D7 is switched off.
• If the error appears after working on the capacitor
bank, check the cabling and the connections
to the cap bank.
• Check fuse U8 on D8 and fuse U1 on D7.
• Check the capacitance in the capacitor bank,
refer to “P03 - Capacitor bank and charging test”.
• Internal short-circuiting in a capacitor or in the
capacitor bank, refer to “Battery circuit and power
transmission unit”.

 Error 17, like John D. posted, is capacitor bank charging error. Be VERY careful about checking the U101 fuse and the fuses in the capacitor banks. If you find an open fuse, you'll need to manually discharge that part of the cap bank. Even with S10 in 'Discharge' position, if a capacitor bank has a blown fuse, any voltage on that part of the bank will NOT get discharged.

 Hopefully, you have the service manual for Mobilett II. Read it, heed it, understand it. Those capacitor banks can be very dangerous.