Suzuki GRAND VITARA Owner's Manual page 1660

10B-24 Body Electrical Control System:
DTC Detecting Condition and Trouble Area
DTC detecting condition
BCM can not receive CAN data from ECM for
longer than specified time continuously.
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.
Troubleshooting
Step
1 Check DTC in BCM
Is DTC U1100 (No. 1100) and DTC U1073 (No. 1073)
detected together?
2 Check each control module connectors
1) Check connection of connectors of all control modules
communicating by means of CAN.
2) Recheck BCM for DTC.
Is DTC U1100 (No. 1100) detected?
3 CAN communication circuit check
1) Turn ignition switch to OFF position.
2) Disconnect connectors of BCM, ECM and ABS hydraulic
unit/control modules communicating by means of CAN.
3) Check CAN communication circuit between control
modules for open, short and high resistance.
Is each CAN communication circuit in good condition?
4 DTC Check
1) Turn ignition switch to OFF position.
2) Connect connectors to BCM, ECM and ABS hydraulic
unit/control module.
3) Check DTC for ABS hydraulic unit/control module.
Is DTC U1100 detected by ABS hydraulic unit/control
module?
• CAN communication circuit
• BCM
• ECM
Action
Trouble area
Yes
Go to "DTC U1073 (No.
1073): Control Module
Communication Bus
Off: ".
Go to Step 3.
Go to Step 5.
Check ECM power and
ground circuit. If circuit
is OK, substitute a
known-good ECM and
recheck.
No
Go to Step 2.
Intermittent trouble.
Check for intermittent
referring to "Intermittent
and Poor Connection
Inspection: in Section
00".
Repair circuit.
Substitute a known-
good BCM and recheck.