Sun Sensor
Multi zone Auto Climate Control systems. Left and right outlet temperatures do not
match when system is in "sync" . Occupants will experience being cold ( winter
time), on either passenger or driver side, even though the temperature setting is the
same. Root cause: Suspect sun senors ( PN 55111274AA and 55111275AA).
THERE WILL BE NO DTC FOR THE SUN SENSOR active or stored. The issue is
diagnosed by using an INCANDESCENT (not LED) shop lamp. Shine the shop
lamp on the left side of the sensor, then on the right side of the sensor, while
monitoring sensor output with STARSCAN. The reading should change from 0 (or
near zero) to about 20 to 40. The important thing is that the left and right readings
are the same, and that they change when the lamp is shone on it.
