Code 21 - Idle (Vacuum) Switch & Map Sensor

NOTE: If Codes 21 and 23 exist, start with Code 23.

Fig 1: Code No. 21 Schematic, Idle (Vacuum) Switch & MAP Sensor

Courtesy of ISUZU MOTOR CO.

Fig 2: Code No. 21 Flow Chart, Idle (Vacuum) Switch & MAP Sensor

Courtesy of ISUZU MOTOR CO.