DELPHI EFI 6. Check circuits (input, ground), from wire harness connector to sensor plug for continuity, damage, etc. Connect one ohmmeter lead to Black pin 14 in wire harness connector (as in step 4). Connect other lead to terminal #1 in sensor plug. Continuity should be indicated. Repeat test between Black pin 10 and terminal #2 in sensor plug. Cutaway Oxygen Sensor Components (O 2 ) Intake Air Temperature Sensor A nonserviceable component. Complete replacement is required if it is faulty. Sensor and wiring harness can be checked as follows. 1. Remove temperature sensor from throttle body. 2. Allow it to reach room temperature (20°C, 68°F). 3. Unplug Black connector from ECU. 4.
With sensor still connected, check temperature sensor circuit resistance between Black pin 10 and 8 SLQWHUPLQDOV9DOXHVKRXOGEHџ 5. Unplug sensor from wire harness and check sensor resistance separately across two pins. Resistance YDOXHVKRXOGDJDLQEHџ D ,IUHVLVWDQFHLVRXWRIVSHFLїFDWLRQVUHSODFH temperature sensor. E ,ILWLVZLWKLQVSHFLїFDWLRQVSURFHHGWR6WHS 6. Check circuits (input, ground), from main harness connector to sensor plug for continuity, damage, etc. Connect one ohmmeter lead to Black pin 8 in main harness connector (as in step 4). Connect other lead to terminal #1 in sensor plug. Continuity should be indicated. Repeat test between Black pin 10 and terminal #2 in sensor plug.
Temperature must be controlled very accurately and gas constituents measured to a high degree of accuracy for absolute sensor measurements. This requires laboratory HTXLSPHQWWRGHWHUPLQHDJRRGRUEDGVHQVRULQїHOG Furthermore, as with most devices, intermittent problems DUHGLIїFXOWWRGLDJQRVH6WLOOZLWKDJRRGXQGHUVWDQGLQJ of system and sensor, it is possible to diagnose many VHQVRUSUREOHPVLQїHOG Using diagnostic software connected to ECU is a useful technique for observing sensor performance. However, user must understand that such software reads a signal generated by ECU. If there is an ECU or wiring problem, readings could be misinterpreted as a sensor problem.
Digital nature of signal to software means that it is not reading continuous output of sensor. A voltmeter can also be used as an effective tool in diagnosing sensors. It is advisable to use an electronic meter such as a digital voltmeter. Simple mechanical meters may place a heavy electrical load on sensor and cause inaccurate readings. Since resistance of sensor is highest at low temperatures, such meters will cause largest inaccuracies when sensor is in a cool exhaust. Visual Inspection 1. Look for a damaged or disconnected sensorto engine harness connection. 2. Look for damage to sensor lead wire or associated HQJLQHZLULQJGXHWRFXWWLQJFKDIїQJRUPHOWLQJRQD hot surface. 3.
Disconnect sensor connector and look for corrosion in connector. 4. Try reconnecting sensor and observe if problem has cleared. 5. Correct any problems found during visual check. Oxygen Sensor (O 2 ) Components Pin A Pin D Pin B Pin C 32 KohlerEngines.com 24 690 01 Rev. D G D F E A C B A Protection Shie ld B Planar Element and Heater C Lower Insulat or D Stainless Steel Housing E Upper Insulat or F Terminal Connection to Element G High Temp Water Seal