Indirect Passenger/Truck

This system does not measure the tire pressure, but rather only its effects; therefore, it is not very accurate. It is based on wheel rotation and behavior, with respect to the other wheels. This system is typically found in passenger vehicles and not on heavy trucks.

 

Pros:

  • No batteries to replace. This system does not have any battery operated sensors

  • No RF Signals. This system does not utilize Radio Frequency transmitting

  • Mostly software based on only a few extra sensors or it’s using existing ABS sensors

 

Cons:

  • This system cannot detect underinflated tires if two tires are low on one axle or one side

  • All four underinflated. Since all tires naturally leaks air, this system will not pick up an under inflation if all four tires are low

  • Different tires. By replacing one tire, the thread height may be slightly off and the system will detect this as an under inflation on the other tire it is comparing to

  • Big PSI drop before warning. To avoid many false alarms, this system requires major under inflation before warning

  • Long drive before warning. This system normally needs about 10 minutes of driving before it realizes any under inflated tire.

  • Difficult to recalibrate. Resetting the system after changing tires with different thread wear is often time consuming and difficult