Are you sure you have D1?

D1 : TRAC KO
This alarm signals that the (M11) Master traction logic unit is not comunicating.
Check:
- The supplying: 48V must be present in the connector JT1 pin A1 cable M
- The can-bus connections
If the supplying is ok, but it do not permits the truck working, replace the Master traction logic unit.

1D : left encoder lock

Interrupted or disconnected left motor encoder.
The alarm appears after 10 seconds approximately with the accelerator pedal pressed.
The machine works at reduced speed and at maximum current.
Encoder basic electric diagram.
In picture it is shown only a signal (A).
The encoders generate two same signals, but out
of phase of 90°(A-B).
1. Connect the positive tip of the tester (red) to
the positive one of the encoder.
2. Connect the COM tip of the tester (black) to
the encoder signal (A).
In base of the motor position, it will show the
following values:
* low signal: 0,5 - 1,5 Volt
* hight signal: 10,5 - 11,5 Volt
It is not possible to read intermediate values with
the motor stopped.
If the motor is working, the multemeter will
automatically read the Mv (medium value)
Mv= 5,5 - 6,5 Volt
Carrying out this test directly on the logic
connectors it is possible to determine if the
signals are good (see upper description) or if the
channels are opened or in shour circuit. If the
signals are good, the problem could be on the
electronic control