Dtc B1541: Hvac Control Module Back-Up Power Supply Malfunction - Suzuki Swift Sport 2004 Service & Repair Manual

7B-62 Air Conditioning System: Automatic Type
Step
11 Position sensor circuit check
1) Check air flow control actuator position sensor circuit
referring to Step 1 to Step 5 and Step 10 to Step 11 of
"DTC B1512: Air flow Control Actuator (Position Sensor)
and/or Its Circuit Malfunction".
Is it in good condition?
12 Air flow control actuator check
1) Check air flow control actuator referring to "Air Flow
Control Actuator Inspection".
Is it in good condition?

DTC B1541: HVAC Control Module Back-Up Power Supply Malfunction

Wiring Diagram
2
3
1. HVAC control module
DTC Detecting Condition and Trouble Area
Back-up power supply voltage is lower than specified value continuously.
DTC Troubleshooting
Step
1 DTC check
1) Turn ON ignition switch 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?
2 Battery voltage supply circuit check
1) Disconnect connector from HVAC control module with
ignition switch turned OFF.
2) Check for proper connection to HVAC control module
connector at "G52-16" terminal.
3) If OK, measure voltage between "G52-16" terminal of
HVAC control module connector and vehicle body
ground.
Is voltage 10 – 14 V?
Action
1
G52-16
WHT/RED
2. Junction block assembly
DTC Detecting Condition
Action
Yes
Go to Step 12.
HVAC control module
faulty.
G52
8 7 6 5 4 3 2 1 10
16 15 14 13 12 11 10 9 20
3. Circuit fuse
• Battery voltage supply circuit
• HVAC control module
Yes
Go to Step 2.
HVAC control module
faulty.
No
Repair circuit.
Air flow control actuator
faulty.
S7RS0B7224017
G51
9 8 7 6 5 4 3 2 1
19 18 17 16 15 14 13 12 11
I5RS0A722015-01
Trouble Area
No
Intermittent trouble.
Check for intermittent
referring to "Intermittent
and Poor Connection
Inspection in Section
00".
Circuit fuse blown and/
or "WHT/RED" wire
circuit open or short.