Circuit Description

Powertrain Control Module (PCM) supplies a 5-volt reference signal and a ground circuit to Manifold Absolute Pressure (MAP) sensor. As manifold pressure changes, MAP sensor output voltage changes. MAP sensor output voltage should be 2 volts at idle and 4 volts at Wide Open Throttle (WOT).

Conditions required to test for DTC are:

• Idle speed does not vary more than 100 RPM.
• IAC does not vary more than 10 counts.
• TP sensor DTCs P0121-P0123, P1121 and P1122 are not present.
• TP sensor does not vary more than one percent.
• EGR is stable, changing less than 4 percent.
• No status change in brake switch, A/C clutch, TCC or power steering pressure switch.
• MAP value change is greater 10 kPa from expected MAP value, for a total of 10 seconds within a 20-second time sample.