User manual

Poseidon MKVI User Manual
Chapter 4
Page 66
With the Oxygen Sensor removal tool snapped into the oxygen sensor base, press the plunger
button with the thumb (Figure 4.3) to lock it in. While continuing to press the button, pull the
tool away from the electronics module, and the oxygen sensor base (with oxygen sensor
attached) will slide out easily (Figure 4-4).
Whenever an oxygen sensor is changed, the serial number of the new sensor, and its position
(Primary or Secondary) should be logged. This should also be done whenever the positions of
the two oxygen sensors are reversed. Doing so allows the history of the sensor to be tracked
over time and correlated with the logged data associated with that sensor. Such information
can be extremely valuable for detecting when a sensor is nearing the end of its life. The serial
number of the sensor is printed on the sensor label, as shown in Figure 4-5.
Once the oxygen sensor base and sensor are removed from the electronics module, the elec-
trical connection can be unplugged from the back of the sensor. Detach the tool from the
sensor base by releasing the plunger button and pulling it off. The oxygen sensor can then be
removed from the sensor base by unscrewing it (Figure 4-5).
Attach the new oxygen sensor to the oxygen sensor base by screwing it into place. Make sure
the o-ring around the base of the threads on the oxygen sensor is clean and free of any
damage, and that it seals properly when the sensor is screwed down snugly.
Once the sensor is properly attached to the sensor base, the electrical connector on the elec-
tronics module should be attached to the sensor. The sensor has three electrical contact pins
in a straight row, parallel to a at plastic guide tab. Hold the connector so that the three contact
holes line up with the three pins on the sensor, and the two plastic pins on the connector
straddle the at guide tab. Carefully push the connector without bending any of the pins, until
it is completely seated.
Figure 4-5. The oxygen sensor is attached to the
sensor base by threads, sealing by an o-ring.
Oxygen sensor base
Oxygen sensor
Electrical connector
Oxygen sensor serial number