light JAGUAR XJ6 1994 2.G Electrical Diagnostic Manual

E I ect r ica I
15.4.10 ELECTROCHROMATIC REAR VIEW MIRROR
15.4.10.1 Description
The function of the electrochromatic rearview mirror is to vary the reflectivity of the mirror glass. The mirror automati- cally varies its reflectivity to accommodate changes in traffic and light conditions to provide the driver with optimized
forward and rear vision.
The mirror contains an ambient sensor (forward facing) and
a glare sensor (rearward facing). Sensitivity control is
adjustable and at the lowest end of sensitivity control is system off. A reverse over-ride facility is incorporated; when
reverse gear is selected, the mirror operates in a high reflective state.
15.4.10.2 Test Procedure
The ambient and glare sensors and associated circuitry, the sensitivity control and reverse over-ride circuitry are all
contained within the mirror unit. Therefore only the inputs to the mirror unit can be interrogated, and if correct, the
mirror unit is defaulted.
. Measure voltage between mirror pin 1 and ground. Value should indicate battery voltage, i.e. 12V nominal.
. If an abnormally low or zero voltage is recorded, check fuse F14, RH 'A' post fuse-box, check wiring harness continu-
. Check the ground connection at the mirror unit pin 3.
Note: The mirror unit shares a common ground with the roof console and the sliding roof, therefore a fault within
the ground would effect all three systems.
. Check for 12V at mirror unit pin 2 when reverse gear selected, ignition ON; falling to OV on deselection of reverse.
/
ity between mirror unit pin 1 and fuse F14.
----- I +12VIGN ! I I I
I
L',
I I
I ,,J
F14 1. Mirror assembly
2. RH A post fuse-box
3. RearLCM
4. RH reverse lamp
5. Roof console (GND) 6. Sliding roof CM (GND)
J86-1864
Fig. 1 Electrochromatic Rear View Mirror Schematic
Issue 1 August 1994 15.4 - 36 X300 EDM