The reason the lamp went out is that the problem wasn't present during the
last three consecutive trip cycles. If the problem again returns for two
consecutive cycles, the lamp will come back on.
In fact, there's a reasonable likelihood the problem wasn't even present
when the technician did his testing. As much as good technicians don't
like it, repairing intermittent problems often requires experiential
knowledge. The language on the repair order is most likely necessary for
warranty regulations-- technically, the sensor isn't to be replaced unless
the technician can show it's defective. In most cases, this is much more
productive than the following: "The problem isn't present right now so
I've cleared the light and codes. Come back to the service department
when the lamp comes back on." Of course, if it turns out to be some sort
of oddball problem, it'll be very difficult to find.
In the scope of things, this is a minor issue. The main purpose of this
oxygen sensor is to monitor catalyst efficiency through comparison to the
B2/S1 oxygen sensor.
Message posted using http://www.talkaboutautos.com/group/alt.autos.hyundai /
More information at http://www.talkaboutautos.com/faq.html