Tachometer Malfunction: Description
WARNING: This page is about a different car, the 2009 Lexus IS 350 and 2009 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.
- The meter CPU receives engine speed signals from the ECM in this circuit.
- The ECM transmits engine speed signals as pulses to the meter CPU.
- The meter CPU calculates the engine speed converting 3 pulses to 1 revolution.