| CAUTION | If ECM replacement is instructed in following testing, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair as necessary and repeat testing to confirm ECM malfunction. |
Circuit Description
MAF sensor uses a platinum hot wire maintained at a constant temperature. Airflow past sensor affects temperature and current flow through sensor. DTC is set when ECM detects an open or short circuit with engine speed at 4000 RPM or less. ECM will operate in fail-safe mode if DTC P0100 is set. Possible causes are
- MAF circuit open or shorted.
- MAF sensor.
- ECM.