Suzuki 2006 SX4 Service Manual page 826

6C-24 Power Assisted Steering System:
DTC Detecting Condition and Trouble Area
DTC detecting condition
DTC C1121:
Vehicle speed signal is 0 km/h even though engine speed
is more than 4000 rpm for more than 60 seconds
continuously (before elapse of 5 min from engine start)
or
Vehicle speed signal is 0 km/h even though engine speed
is more than 2500 rpm for more than 60 seconds
continuously (after elapse of 5 min for engine start).
(1 driving cycle detection logic but "EPS" warning light
does not light up)
DTC C1123:
Vehicle speed signal is 0 km/h with continuously more
than 3 driving cycles even though engine speed is more
than 4000 rpm for more than 30 seconds continuously
(before elapse of 5 min from engine start)
or
Vehicle speed signal is 0 km/h with continuously more
than 3 driving cycles even though engine speed is more
than 2500 rpm for more than 30 seconds continuously
(after elapse of 5 min for engine start).
(3 driving cycle detection logic)
DTC C1124:
Vehicle speed signal is less than 5 km/h for more than 5
seconds continuously with more than specified
deceleration speed (–20 m/s
(1 driving cycle detection logic but "EPS" warning light
does not light up)
DTC Troubleshooting
Step
1 Was "EPS System Check" performed?
2 DTC check
1) Check ABS control module and BCM for DTC referring
to "DTC Check in Section 4E" and "DTC Check in
Section 10B".
Is there any DTC(s) detected?
3 DTC check
1) Check ECM for DTC referring to "DTC Check in Section
1A".
Is there any DTC(s) detected?
4 Vehicle speed signal circuit check
1) With ignition switch turned OFF, disconnect connectors
from BCM.
2) Check BCM connector for proper connection.
3) If OK, turn ON ignition switch, measure voltage between
"G04-22" wire terminal of BCM connector and body
ground.
Is voltage 4 – 5 V?
2 ) from over 20 km/h.
Action
Trouble area
• Vehicle speed signal circuit
• BCM
• ECM
• ABS control module
• P/S control module
• CAN communication line circuit
Yes
Go to Step 2.
Go to applicable DTC
diag. flow.
Go to applicable DTC
diag. flow.
Go to Step 5.
No
Go to "EPS System
Check".
Go to Step 3.
Go to Step 4.
Go to Step 6.