E151 = No communication with drive motor frequency
converter on start-up.

Check the CAN cables - Weak point on the Reflex is the wiring where it exits the top of the upright cab piller the cables can rub where they enter the roof to the diagnostic port & cause short circuits that will upset the CAN system.

Burnt / overheated fuses can upset the CAN system to, even if the main system fuses check out fine with a multimeter if there is any heat damage to the fuse inside the glass window I would replace it.

Have a look at the A1 box under the armrest, there should be 2 identical boxes towards the right hand end of the armrest panel, you want to check the lefthand one of these boxes, look at the green led on the box & see if its ON, OFF or flashing.