Dtc B1541: Back-Up Power Supply Circuit Malfunction - Suzuki 2006 SX4 Service Manual

DTC B1541: Back-Up Power Supply Circuit Malfunction

Wiring Diagram
2
3
WHT
[B]: Back-up power supply circuit
1. HVAC control module
DTC Detecting Condition and Trouble Area
• Back-up power supply voltage is lower than specified value continuously.
• When connect battery with vehicle and then, turn ignition switch to ON
position for first time.
NOTE
When checking DTC after connecting battery cable, be sure to turn ignition switch from OFF to ON and
from ON to OFF at least once, or DTC B1541 will be detected.
DTC Troubleshooting
Step
1 Was "Air Conditioning System Check" performed?
2 DTC check
1) Turn ignition switch to ON position for 20 sec. or more.
2) Ignition switch turned OFF and connect scan tool to
DLC.
3) Turn ON ignition switch and check DTC.
Is there DTC B1541?
3 Battery voltage supply circuit check
1) Disconnect connector from HVAC control module with
ignition switch turned OFF.
2) Check for proper connection to back-up power supply
circuit terminal of HVAC control module connector.
3) If OK, measure voltage between back-up power supply
circuit terminal of HVAC control module connector and
vehicle body ground.
Is voltage 10 – 14 V?
1
[B]
WHT/RED G20-7
5V
12V
DTC Detecting Condition
Action
Air Conditioning System: Automatic Type 7B-69
14 13 12 11 10 9 8
30 29 28 27 26 25 24
2. Main fuse
3. Circuit fuse
• Battery voltage supply circuit
• HVAC control module
Yes
Go to Step 2.
Go to Step 3.
Substitute a known-
good HVAC control
module and recheck.
S6RW0D7224018
G20
7 6 5 4 3
23 22 21 20 19 18 17
Trouble Area
No
Go to "Air Conditioning
System Check".
Intermittent trouble.
Check for intermittent
referring to "Intermittent
and Poor Connection
Inspection in Section
00".
Back-up power supply
circuit is open or
shorted to ground.
2 1
16 15
I7RW01722011-01