Chery A21 2005, Service Manual, Page: 276 / 475

The 30th power line sup ply power to the fro nt ISU via the fuse FB 29, and then via the fuse
F10 and output from the C14 pin of ISU to supply power to key hole illumination lamp 、 glove box
lamp 、 ma ke up mirror 、 front roof lamp 、 rear roo f lamp.
The B14 of fro nt ISU is the F/L contact switc h; the B30 of front ISU is the F/R contac t switch.
When the indoor illumination lamp switch is at the left side or right side (door control
position), the front I SU computer will control the inner illum ination lamp (roof lamp work).
When the igni tion powe r is off, if o ne of the 4 doors is open, the inner illum ination lamp will
light on; while afte r 15 min, the inn er illumination lamp will be off automatically to save
The parts that controlled by the front ISU have the f ollowing functions:
（ 1 ） Inner lamp control and steering lamp
、 he adlamp high/low beam;
（ 2 ） Central con trol lock function
（ 3 ） Button-typ e electric window operation function
（ 4 ） Intermission time control of window wip er
（ 5 ） Delay the cl ose time of electric window when the ignition sw itch is off
（ 6 ） Rear view mirror heating control fuction (the adjustment of the motor is
Con trolled by switch )
（ 7 ） Key not pull out warning
（ 8 ） Warning and anti-theft
（ 9 ） CAN-BUS data transfer(with i nstrument
、 engine 、 ABS computer)
Front Ground/
Left 2 /8 Front Gr ound/
R ight /5 Front
Rear Windshield
Warmer Switch
Front ISU
30
15
ACC1
ACC2
31
ILLUM
ON
O FF
O N
O FF
C14
A23
C6 B14 B30
F10
7.5A
FB29
80A
E
R R P/L
Instrument/FrontGround/G
Instrument/FrontGround/A2
9 9 10
O W
Keyhole Light
Clove Box Switch
Front Ceiling Light
Clove Box Switch
F igure14- 3 Vehicle inner illumination lamp circuit
2 ． Vehicle inner illumination lamp
1 ． Front ISU
Figure14-2 Front ISU
C wire plug 20
A wire plug 32
E power
D wire plug 12
F gr ound
B w ire plug 32
electricity.
When the ignition p ower is off, open one door, the inner illumination lamp will light on
until the door is c losed, and will continue to lig ht for 15s after the door closed.
When the ignition po wer on, the inner illumination lamp will light on only when the door is
open, a nd be off when the door is closed.
illumin ation
illumination
The A23 p in of front ISU is the key hole lamp signal output pin, when the
ignition power is off, the key lamp will light on if open the drive r 's door. Even if the
driver's door is closed, the lamp will continue to light on for 8s. Shown as figu re 14-3.
2 8
A5 has two vehicle body computer, one is front ISU shown as figure 14-2 ,
the other is rear ISU .
（