DTC 33

Code 33 Chart:

Code 33 Wiring Diagram:

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.


NOTE: Because of all the possible color code combinations used on electrical wiring diagrams, always refer to ECM CONNECTOR IDENTIFICATION under ELECTRICAL AND ELECTRONIC WIRING DIAGRAMS for correct color code identification of circuit.


TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. Code 33 will set when:

^ Engine Running.
^ Manifold pressure greater than 75.3 kPa (A/C "OFF") 81.2 kPa (A/C "ON").
^ Throttle angle less than 2% Conditions met for 2 seconds.

2. With the MAP sensor disconnect the ECM; should see a low voltage if the ECM and wiring is OK.


DIAGNOSTIC AIDS:



An open in circuit 455 or the connection will result in a Code 33. Ignition "ON" engine "OFF" voltages should be within the table on the chart above. Also, CHART C-1D can be used to test the MAP sensor.

Refer to TESTING PROCEDURES/DIAGNOSIS BY SYMPTOM/INTERMITTENTS.