WABCO OptiTire System Description page 61

Operation
System failure
Battery warning
A system failure has occurred if display shows crossed-out "IVTM". OptiTire
does not signal warning messages for any wheel. The driver must check the tire
pressures manually on the wheel.
System error
Repair note
– Check the supply voltage of the ground line.
– Check the cable connections.
– Carry out a system diagnosis.
If the wheel sensor battery's end of life has been reached after around 9 years,
a battery warning is set around half a year beforehand. This is indicated in the
display by a flashing sensor and a corresponding battery symbol. No warning
lamp is indicated.
TM
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