Toyota Celica 2005 Repair Manual page 1273

DI−1072
Electronically Controlled Transmission Communication Circuit
CIRCUIT DESCRIPTION
When driving uphill under the cruise control and the shift−down occurred in the electronically controlled
transmission, the cruise control ECU sends a signal there to suspend the shift−up until the vehicle reaches
the top of the hill. This will provide smooth driving, and there is no need for ON−OFF overdrive operation.
Terminal ECT of the cruise control ECU detects the shift change signal (output to electronically controlled
transmission No. 2 solenoid) from ECM.
If the vehicle speeds down and when terminal ECT receives the shift−down signal, ECU sends a signal from
terminal OD to ECM to stop the overdrive until the end of the uphill slope, and the gear shift points in the
electronically controlled transmission are changed.
WIRING DIAGRAM
E1
ECT Solenoid
2005 CELICA (RM1131U)
DIAGNOSTICS
J2
Junction
Connector
Y
B
S2
B
10 B
B
Y
E5
20
S2
ECM
− CRUISE CONTROL SYSTEM (1ZZ−FE)
3
Y
Y
EA1
1
B
E3
OD1
1272
C18
Cruise Control ECU
8
Y
6
IE3 ECT
19
14
B
OD
IE3
DI08U−35
I26001