Suzuki GRAND VITARA JB416, Service Manual

Page: 437 / 474

Body Electrical Control System: 10B-17
DTC U1144 (No. 1144): Lost Communication with Keyless Start Control Module
S5JB0EA204016
Wiring Diagram
Refer to “DTC U1073 (No. 1073): Control Module 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.
DTC Troubleshooting
DTC detecting condition Trouble area
BCM can not receive data sent by CAN from keyless start
control module for longer than specified time continuously. • CAN communication circuit
• Keyless start control module
• BCM
Step Action Yes No
1 DTC check of BCM
Is DTC U1144 (No. 1144) and DTC U1073 (No. 1073)
detected together?
Go to “DTC U1073 (No.
1073): Control Module
Communication Bus
Off: ”. Go to Step 2.
2 DTC check of keyless start control module
1) Check keyless start control module for DTC.
Is DTC No. 33 detected?
Go to “DTC No. 33:
Control Module
Communication Bus
Off: in Section 10E”. Go to Step 3.
3 Control module connector check
1) Check connection of connectors of all control modules
communicating by means of CAN.
2) Recheck BCM for DTC.
Is DTC U1144 (No. 1144) detected?
Go to Step 4. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection: in Section
00 in related manual”.
4 CAN communication circuit check
1) Turn ignition switch to OFF position.
2) Disconnect connectors of BCM and keyless start control
module communicating by means of CAN.
3) Check CAN communication circuit between BCM and
keyless start control module for open, short and high
resistance.
Is each CAN communication circuit in good condition?
Go to Step 5. Repair circuit.
5 CAN communication circuit check
1) Disconnect connectors of all control modules
communicating by means of CAN.
2) Check CAN communication circuit between control
modules other than Step 4 for open, short and high
resistance.
Is each CAN communication circuit in good condition?
Go to Step 6. Repair circuit.
6 Key indicator lamp operation check
1) Connect connectors of disconnected control modules
communicating by means of CAN.
2) Push ignition knob switch of steering lock unit.
Does key indicator lamp turn ON?
Go to Step 7. Check keyless start
control module power
and ground circuit. If
circuit is OK, substitute
a known-good keyless
start control module and
recheck.