Bendix

TESTING PROCEDURE:

NOTE: While trouble shooting, always check the wiring, fuses and connectors for good condition and routing. Use the wiring diagrams found in CHASSIS ELECTRICAL DIAGRAMS to supplement your testing efforts.

Color Code Legend:

Checking Oxygen Sensor (Lambda Sond) Pre-Heater Resistance:

1. Disconnect connector at right A-post.
2. Connect a voltmeter between ground and #8 connection in 25 terminal connector.
a. With sensor cold (68°F or 20°C):

Reading: approx. 3 ohms

b. With sensor hot (over 660°F or 350°C which is the temperature of the sensor when the engine is hot during idle):

Reading: approx. 13 ohms

3. If reading is correct, heating element is O.K., proceed with step 4.
If reading is incorrect, check wiring and connectors to and from sensor. Repair as necessary. If no fault is found in wiring, replace and retest with new oxygen sensor.

Connecting CO Meter:

4. Connect a CO-meter to the test port in the exhaust system. Use VOLVO tool #5410 or equivalent to access the test port.
5. Run engine to operating temperature.
6. Check CO content at idle.

CO should be: 0.4 - 0.8%

Disconnecting Oxygen Sensor Lead:

7. Separate the oxygen sensor (lambda sond) connector.
a. If the CO level drops below 0.4%, check intake system for air leaks and repair as necessary.
b. If the CO level rises above 0.8%, check fuel injectors for fuel leaks and check fuel system pressure (see FUEL SYSTEMS), repair as necessary.

Checking ECU:

8. Ground lead to ECU.
a. The CO content should now rise, indicating correct operation of the ECU and wiring.
b. If the CO content does not rise, fault lies in the wiring or the ECU. Check wiring and repair as needed.

Checking Oxygen Sensor:

9. Connect a voltmeter to the wire from the sensor.

The voltmeter needle should average: 0.5 volts with correct CO content (0.4 - 0.8%)

This will show that the oxygen sensor is operating correctly.
If oxygen sensor fails this test, replace and retest with new sensor.
10. Reconnect the oxygen sensor connector. Let engine run for three (3) minutes and recheck the CO content.

CO should be: 0.4 - 0.8%

11. If vehicle passes all tests and CO is not within specifications (0.4 - 0.8%), retest with new fuel injection ECU.
12. Disconnect the test equipment, remount all panels and the glove compartment.