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Exception: In a dangerous situation, towing without
separation of the drive train is permitted until the
vehicle has left the danger area (e.g. intersection,
tunnel, etc.).
In such a case the following conditions apply:
• Push-button range selector in Neutral position.
• Max. towing time 10 minutes.
• Max. towing speed: 15 km/h
NOTE
At an ambient temperature below -15°C, the
maximally permitted towing speed is 5 km/h.
(12) Temperature Monitoring
Transmission temperature monitoring is performed
by the electronic control unit. Oil sump temperature
and the oil temperature on the retarder output are
sent to the vehicle computer via CAN. Depending on
the vehicle application,
alert signals will be issued when the permissible
temperature limit values are exceeded.
Consult the vehicle operating instructions for more
details.
When the permissible temperature limit values are
approached during retarder operation, retarder
performance will be reduced by the electronic
control unit.
Action to be taken in the event of a temperature
alert:
• Drive in partial-load range
• Using the “Retarder ON/OFF” switch:
Deactivate the retarder.
If this does NOT cause the oil temperature to drop:
• Stop the vehicle.
• Put push-button range selector in Neutral position.
• Run engine at raised idle speed.
NOTE
If, after a few seconds, the temperature does not
decrease to the permitted range, this may be due to:
• Oil level too low or too high.
• Contaminated vehicle heat exchanger.
• Defective cooling circuit.
• Transmission damage
Inform ZF Service Center!
(13) Status Monitoring / Warning Lamps
The diagnostics system of the electronic control unit
monitors the transmission status every time the
vehicle system voltage is switched on and
continuously while the vehicle is in motion.
Warning lamps
Faults are indicated by warning lamps lighting up (red
or yellow) and/or by warning messages which appear
on the driver’s display panel (consult the vehicle
operating Instructions).
If a selected driving range is not accepted by the
ECU, the push button depressed on the push-button
speed range selector will flash.
(14) Transmission Response to a Malfunction
To protect the transmission in the event of a
malfunction, the following responses are provided:
Shift into Neutral:
In the event of serious malfunctions in the power
supply to the transmission, e.g. short circuit.
Engagement of emergency operation mode:
If there is an interruption of CAN communication or a
loss of speed information.
DANGER !
The following applies in the event of a malfunction of
the transmission system:
• Serious risk of transmission damage
• Limited system monitoring RISK OF ACCIDENT!
• Continuation of the trip is only allowed if the utmost
care is practiced by driving as slowly and foresighted
as possible.
Emergency Operation
Depending on the fault prevailing, the following
limitations may occur during emergency operation:
• Retarder function limited or not available.
• Automatic Idle Shift (AIS) function not available.
• No activation of the engine brake.
• Torque converter lockup clutch (WK) open.
• Limitation of engine torque for transmission
protection (no engine control).
• Poorer shifting quality or no gearchanges.