H2 OEM Off Road Lights

[SummitUp]

Wrong again! Let me set this straight. The gray things that are on the end of the blue plugs are temperature sensors. The outboard one (the one on the left in the photo) sends the data signal for the outside ambient air temperature to the temp display on the interior rear view mirror.

You can prove this for yourself by disconnecting the gray sensor from the outboard plug, and you will see the temp display on the rear view mirror no longer displays the temp, but displays an error message "OC" instead.

If you then take the gray sensor from the other plug (the one on the right), and plug it into the plug on the left (swap them in other words), the temp display on the rear view mirror is working again. Therefore they are both identical temp sensors.

The inboard one (on the right in the photo) is there so the HVAC PCM knows what the ambient air temperature is, i.e. for the heating and air conditioning. I've verified this in the factory service manual (page 1-151). So... there it is.