Honda Accord 2008 Manual page 1074

Automatic Transmission
System Description (cont'd)
Electronic Control System (cont'd)
C l u t c h P r e s s u r e C o n t r o l
T h e P C M a c t u a t e s A / T c l u t c h p r e s s u r e c o n t r o l s o l e n o i d v a l v e s A, B, a n d C t o c o n t r o l t h e c l u t c h p r e s s u r e . W h e n s h i f t i n g
b e t w e e n g e a r s , t h e c l u t c h p r e s s u r e r e g u l a t e d b y A / T c l u t c h p r e s s u r e c o n t r o l s o l e n o i d v a l v e s A , B, a n d C e n g a g e s a n d
d i s e n g a g e s t h e c l u t c h s m o o t h l y .
T h e P C M r e c e i v e s i n p u t s i g n a l s f r o m t h e v a r i o u s s e n s o r s a n d s w i t c h e s , p r o c e s s e s d a t a , a n d o u t p u t s c u r r e n t t o A / T
c l u t c h p r e s s u r e c o n t r o l s o l e n o i d v a l v e s A , B, a n d C.
input S h a f t
(Mainshaft)
S p e e d S e n s o r S i g n a l
O u t p u t S h a f t
(Countershaft)
S p e e d S e n s o r S i g n a l
Throttle Position
S e n s o r Signal
Manifold Absolute
Pressure Sensor Signal
Engine RPM Signal
B a r o m e t r i c P r e s s u r e
S e n s o r S i g n a l
2nd Clutch
Transmission Fluid
Pressure Switch Signal
3rd Clutch
Transmission Fluid
Pressure Switch Signal
4th Clutch
Transmission Fluid
Pressure Switch Signal
Engine Coolant
Temperature
S e n s o r Signal
A T F Temperature
S e n s o r Signal
P C M
Actual
Driving
Shift
Position
Decision of
Shifting Mode
Master Target of
Controlling Current
Correction of Data
Current
Feedback
Current
Feedback
Current
Feedback
Correction for
Engine Torque
Signal Data
C o r r e c t i o n for
Hydraulic P r e s s u r e
A p p l i c a t i o n
T i m i n g
C o r r e c t i o n for
E n g i n e C o o l a n t
T e m p e r a t u r e
S e n s o r S i g n a l Data
Correction for A T F
Temperature
Sensor Data
A / T Clutch Pressure
Control Solenoid
Valves A, B, and C
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