Dtc Detecting Condition - Suzuki GRAND VITARA JB416 Service Manual

1A-30 Engine General Information and Diagnosis:

DTC Detecting Condition

When ECM receives a trouble code from TCM, which indicates that some problem occurred in sensor circuits and its
calculated values used for operations such as idle speed control, engine power control, and so on by TCM, ECM sets
DTC P1603. (TCM outputs the trouble code to ECM when TCM can not compute the engine control signal due to
malfunctions of sensor circuits used for gear shift control.)
DTC Troubleshooting
NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
"Precautions For DTC Troubleshooting: in related manual".
Step
1 Was "Engine and Emission Control System Check"
performed?
2 DTC check
1) Check DTC of TCM referring to "DTC Check: in Section
5A in related manual".
Is there any DTC(s)?
Action Yes
Go to Step 2.
Go to applicable DTC
diag. flow.
No
Go to "Engine and
Emission Control
System Check: in
related manual".
Substitute a known-
good ECM and recheck.