DTC 34

Fig. 010 - Wiring Diagram for Code 34 MAF Sensor. VIN L:

CODE 34

MAF SENSOR

3.0L "N" SERIES

FUEL INJECTION (PORT)

The MAF Sensor measures the flow of air entering the engine. This information is used by the ECM for fuel control.
Code 34 is set when either of the following sets of conditions exists:
a. Engine running
b. MAF sensor disconnected
OR
c. Engine running over 1400 rpm.
d. TPS over 50% (2.5 volts DC)
e. Air Flow less than 10 grams per second (low frequency).

Fig. 009 - Chart - Code 34 Mass Air Flow Sensor (Signal Frequency Low):

1. A loose or damaged air duct can set code 34.
2. Checks to see if ECM recognizes a problem. A "SERVICE ENGINE SOON" light off at this point indicates an intermittent problem.
3. Checks to see if 5 volt reference signal from ECM is at MAF sensor harness connector. Less than 1 volt at this point indicates a faulty CKT 492, wiring connector, or ECM.
4. Checks continuity of electrical circuit.
5. Checks for open in ignition circuit.