User's Manual

11 | P a g e
4.3 Sensor Lock nuts and wrench
FOBO Ultra sensors and In-Car unit are tied to a FOBO account after
installation. They are not re-usable or transferable without the owner releasing
them from his/her FOBO account. This is a theft deterrent feature to
discourage theft.
As an additional anti-theft feature, all FOBO Ultra package comes with lock-
nuts and special wrench. FOBO Tire Plus‟s functionality is not affected if
you do not use the lock-nuts.
The lock nuts and wrench are made of custom engineering plastics that can
withstand road salts and common automotive chemicals (gasoline, engine oil,
wash shampoo, etc.).
In order to use the lock nuts, you must first install the lock nut to the tire valve
(with the bump facing tire rim). Screw in the lock nut all the way down and
ensure that there is still a minimum of 5 thread count on the tire valve for
the sensor unit to be screwed on. If there is insufficient thread for the tire
sensor, it may lead to air leakage. A solution for this would be to change the
tire valve to one with a longer thread. Next, screw in the tire sensor unit until
it is reasonably tight. Then use your finger to unscrew the lock nut outwards
(i.e. anti-clockwise) until it pushes against the bottom of the sensor unit. Use
the wrench to tighten the lock nut. The resultant friction force will make it
difficult to remove the sensor unit without loosening the lock nut. For rubber
valves, hold the valve stem with one hand and tighten the lock nut with the
wrench on another hand. This is to avoid the rubber valve from twisting
making it unable to tighten the lock nut.