Code 34 - Map Sensor Signal Volt Lo
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 1-1.5 volts at idle to 4-4.5 volts at WOT. If the MAP sensor fails, the ECM will substitute a fixed MAP value and use the TPS to control fuel delivery. Code 34 will set when signal reading is too low and ignition is turned on.
NOTE:
The following step numbers refer to the numbers in the accompanying flow chart(s).
- This test confirms Code 34 and presence of fault.
- If the ECM recognizes and sets Code 33 (high MAP signal), the ECM and wiring are good.