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DTC 33

Code 33 - MAP Sensor:




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







CODE 33 - MAP SENSOR (SIGNAL VOLTAGE HIGH)



Circuit Description:

The Manifold Absolute Pressure Sensor (MAP) 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 fixed MAP value and use the Throttle Position Sensor (TPS) to control fuel delivery.

Code 33 will set if all conditions below are met:

^ Signal is too high for a time greater than 8 seconds.
^ TPS voltage indicates throttle is closed. 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. See Diagnosis By Symptoms - No Trouble Codes Stored.



Test Description:

1. Confirms Code 33 and that fault is still present.


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