Question

technician a says that direct reading tpms will use the wheel speed sensors to estimate the tire pressure
technician b says that indirect reading tpms will have a sensor inside the tire/wheel assembly which sends a pressure signal to the tpms module
who is right?
a. a only
b. b only
c. both a and b
d. neither a nor b

Explanation:

• Direct TPMS: Direct Tire - Pressure Monitoring Systems (TPMS) have sensors inside the tire/wheel assembly that directly measure and send pressure signals to the TPMS module.
• Indirect TPMS: Indirect TPMS uses wheel - speed sensors (from the Anti - lock Braking System, ABS) to estimate tire pressure by detecting differences in wheel rotation speeds (due to changes in tire radius caused by pressure changes).

Technician A is wrong as they confused the functions of direct and indirect TPMS. Technician B is wrong as they described the direct TPMS sensor location for what they called indirect TPMS.

Answer:

D. Neither A nor B