Suzuki GRAND VITARA JB416, Service Manual

Page: 343 / 474

Automatic Transmission/Transaxle: 5A-24
DTC P1777: TCM Lost Communication with ECM (Reception Error)
S5JB0E5104042
Wiring Diagram
Refer to “DTC P1774: CAN Communication Bus Off: ”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC by using scan tool.
3) Start engine and run it for 1 min. or more.
4) Check DTC and pending DTC.
4 DTC check
1) Turn ignition switch to OFF position.
2) Connect connectors of disconnected control modules
communicating by means of CAN.
3) Disconnect connector of any one of control module other
than TCM.
4) Recheck DTC for TCM.
Is DTC P1774 detected?
Disconnect connectors
of control modules other
than the one whose
connector is
disconnected in Step 3)
one by one and check
that DTC P1774 is
detected by TCM each
time connector is
disconnected. When
DTC P1774 is not
detected by TCM while
checking in this way, go
to description under
“NO” below. If DTC
P1774 is detected by
TCM even when
connectors of all control
modules that use CAN
communication with
TCM are disconnected,
substitute a known-
good TCM and recheck. Check power and
ground circuit of control
module disconnected in
Step3). If circuit is OK,
substitute a known-
good control module
disconnected in Step 3)
and recheck.
Step Action Yes No
DTC Detecting Condition Trouble Area
Reception error of communication data for ECM is detected for
longer than specified time continuously.
(1 driving cycle detection logic) • ECM
• ABS/ESP
®
control module
• TCM
• CAN communication line circuit