F35899 — TM: Unknown fault

F35899 “TM: Unknown fault” is raised when a Terminal Module (TM) signals a fault that the firmware on the Control Unit cannot interpret. The manual explains that this happens when the firmware on the Terminal Module is more recent than the firmware on the Control Unit, so the Control Unit has no description for the incoming fault. Every manual that lists the code gives the same text for the Terminal Module component, so one description covers all families. The same condition can also be issued as an alarm (A) or as a message with no reaction (N); the drive's configuration decides. The fault itself triggers no automatic drive response (NONE), and the message can be acknowledged immediately.

• A fault has occurred on the Terminal Module that cannot be interpreted by the Control Unit firmware.
• The firmware on the Terminal Module is more recent than the firmware on the Control Unit, so the Control Unit cannot interpret the fault the Terminal Module reports.

1. Read the fault value in r0949, interpreting it as a decimal number: it contains the fault number of the new fault from the Terminal Module.
2. If required, read about the significance of this new fault in a more recent description of the Control Unit, as the manual's note recommends.
3. Replace the firmware on the Terminal Module by an older firmware version; the manual names r0158 in this step.
4. Alternatively, upgrade the firmware on the Control Unit so that it can interpret the Terminal Module's fault; the manual names r0018 in this step.

• The message value line reads “New message: %1”; the manual gives no further decoding of the placeholder.
• Fault value (r0949, interpret decimal): fault number — the number of the new fault the Terminal Module has reported.

• r0949 (fault value) — read it interpreting decimal to obtain the fault number of the new Terminal Module fault.
• r0158 (VSM FW version) — the parameter the manual names when the Terminal Module firmware is to be replaced by an older version.
• r0018 (CU FW version) — the parameter the manual names when the Control Unit firmware is to be upgraded.

The message can be acknowledged immediately; a POWER ON also removes it. When the drive issues the same condition as an alarm (A) or with no reaction (N), neither a reaction nor an acknowledgement applies (NONE).