Test Description

WARNING: This page is about a different car, the 1995 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Test numbers refer to numbers on diagnostic charts.

Determines if fault is a hard failure or an intermittent condition.
Checks for 5-volt reference from PCM.
Verifies both ignition voltage and a good ground circuit are available.

Fig 1: Code 48 Schematic (Corvette) Mass Airflow Sensor

Fig 2: Code 48 Diagnostic Flow Chart (Corvette) Mass Airflow Sensor