Circuit Description
WARNING: This page is about a different car, the 2003 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
MAF sensor uses a platinum hot wire maintained at a constant temperature. Airflow past sensor affects temperature and current flow through sensor. See Fig 1. If DTC P0100 is set, ECM will operate in fail-safe mode, keeping ignition timing and injection volume constant. DTC P0100 is set when ECM detects an open or short circuit with engine speed at 4000 RPM or less for more than 3 seconds. Possible causes are:
- Open or short in MAF circuit.
- Faulty MAF sensor.
- Faulty ECM.