DTC 33

Code 33 - MAP Sensor (Signal Voltage High):

Wiring Diagram For Code 33 - MAP Sensor (Signal Voltage High):

CODE 33 - MAP SENSOR (SIGNAL VOLTAGE HIGH)



Circuit Description:

The Manifold Absolute Pressure (MAP) Sensor responds to changes in manifold pressure (vacuum). The ECM receives this information as a signal voltage that will vary from about 1 to 1.5 volts at idle to 4 - 4.5 volts at wide open throttle.

If the MAP sensor fails, the ECM will substitute a calculated MAP value based on the Throttle Position Sensor (TPS) and engine speed (RPM) to control fuel delivery.

Code 33 will set if all conditions below are met:

^ Signal is too high for a time greater than 5 seconds
^ TPS voltage indicates throttle is closed.
^ Vehicle speed is "0" MPH.

Engine misfire or a low unstable idle may set Code 33. Disconnect MAP sensor and system will go into backup mode. If the misfire or idle condition remains.


Test Description:

1. Confirms Code 33 and that fault is present.

2. If the ECM recognizes and sets Code 34, low MAP signal, the ECM and wiring are OK.