2004 ISUZU TF SERIES ignition

RESTRAINT CONTROL 9A1-35

DTC B0033 (Flash Code33) ECU Connector Poor Connection


RTW49JLF000101

Circuit Description
The connector of SRS control unit is connected
completely. ECPA(Electrical Connector Position
Assurance) circuit is closed after that.
SRS control unit supervises it by self-diagnosis.

DTC Will Set When
ECPA circuit is open.
Action Taken
Connect completely the SRS control unit.

DTC Will Clear When
The ignition switch is turned “OFF”.

9A1-36 RESTRAINT CONTROL SYSTEM

DTC (Flash Code33) B0033 ECU Connector Poor Connection

Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed?
Go to Step 2 Go to the “SRS
Diagnostic System
Check”
2 Ignition switch “OFF”
Reconnect the ECPA on SRS control unit connector yellow 52-
pin connector located at the base of instrument panel center.
Ignition switch “ON”
Is DTC B0033 current? Go to Step 3 Reconnect the
ECPA properly.
Go to Step2
3 Clear Diagnostic trouble codes.
Is the action complete? Go to “SRS
Diagnostic System
Check” Go to Step 3

9A1-38 RESTRAINT CONTROL SYSTEM

DTC B0051 (Flash Code 51) Squib Circuit Activated (Crash Deteted)
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SRS CONROL UNIT.
NEVER STRIKE OR JAR THE SRS CONTROL UNIT. NEVER POWER UP THE SRS WHEN THE SRS CONTROL
UNIT IS NOT RIGIDLY ATTACHED TO THE VEHICLE. ALL SRS CONTROL UNIT AND MOUNTING BRACKET
FASTENERS MUST BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD THE
FRONT OF THE VEHICLE TO ENSURE PROPER OPERATION OF THE SRS. THE SRS CONTROL UNIT CAUSE
DEPLOYMENT AND RESULT IN PERSONAL INJURY.


Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2. Go to the “SRS
Diagnostic System
Check”
2 Ignition switch “OFF.”
Have air bag assemblies deployed? Replace
components and
perform
inspections as
directed in
“repairs and
inspections
required after an
accident” in this
section.
clear diagnostic
trouble codes.
Repeat “SRS
Diagnostic System
Check” Go to Step 3
3 Inspect front of vehicle and undercarriage for sings of impact.
Were signs of impact found? Replace
components and
perform
inspections as
directed in
“Repairs and
Inspections
Required After An
Accident” in this
section.
Clear diagnostic
trouble codes.
Repeat “SRS
Diagnostic System
Check” Ignition switch
“OFF”.
Replace SRS
control unit.
Reconnect all SRS
system
components,
ensure all
components are
properly mounted.
Repeat “SRS
Diagnostic System
Check”

9A1-40 RESTRAINT CONTROL SYSTEM

DTC Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
2.
If air bag assembly have not deployed, DTC B0053
may have falsely set.
3.
If DTC B0053 has set with no signs of frontal impact,
the diagnostic trouble code has falsely set.


DTC B0053 (Flash Code 53) Deployment Command Despite Present Trouble Code
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SRS CONTROL
UNIT. NEVER STRIKE OR JAR THE SRS CONTROL UNIT. NEVER POWER UP THE SRS WHEN THE SRS
CONTROL UNIT IS NOT RIGIDLY ATTACHED TO THE VEHICLE. ALL SRS CONTROL UNIT AND MOUNTING
BRACKET FASTENERS MUST BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD
THE FRONT OF THE VEHICLE TO ENSURE PROPER OPERATION OF THE SRS. THE SRS CONTROL UNIT
COULD BE ACTIVATED WHEN POWERED WHILE NOT RIGIDLY ATTACHED TO THE VEHICLE WHICH
COULD CAUSE DEPLOYMENT AND RESULT IN PERSONAL INJURY.


Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2 Go to the “SRS
Diagnostic System
Check”
2 Ignition switch “OFF.”
Have air bag assembles deployed? Replace
components and
perform
inspections as
directed in
“Repairs And
Inspections
Required After An
Accident” in this
section.
Clear diagnostic
trouble codes.
Repeat the “SRS
Diagnostic System
Check” Go to Step 3
3 Inspect front of vehicle and undercarriage for signs of impact.
Were signs of impact found? Replace
components and
perform
inspections as
directed in
“Repairs And
Inspections
Required After An
Accident” in this
section.
Clear diagnostic
trouble codes.
Repeat “SRS
Diagnostic System
Check” Ignition switch
“OFF.”
Replace SRS
control unit.
Reconnect all SRS
system
components,
ensure all
components are
properly mounted.
Repeat the “SRS
Diagnostic System
Check”

RESTRAINT CONTROL 9A1-41

DTC B0057 (Flash Code 57) Passenger Pretensioner Squib Circuit Low
Resistance


RTW49JLF000101

Circuit Description
When the ignition switch is turned “ON”, the SRS
control unit will perform tests to diagnose critical
malfunctions within itself. Upon passing these tests
“Ignition 1”, and deployment loop voltages are
measured to ensure they are within their respective
normal voltage ranges. The SRS control unit then
proceeds with the “Resistance Measurement Test”.
“Passenger Pretensioner Low” terminal “43” is
grounded through a resistor and the passenger current
source connected to “Passenger Pretensioner High”
terminal “44” allows a known amount of current to flow.

By monitoring the voltage difference between
“Passenger Pretensioner High” and “Passenger
Pretensioner Low”, the SRS control unit calculates the
combined resistance of the passenger air bag
assembly, harness wiring circuits “Passenger
Pretensioner High” and “Passenger Pretensioner Low”
connector terminal contact.

9A1-42 RESTRAINT CONTROL SYSTEM

DTC Will Set When
The combined resistance of the passenger pretensioner
assembly, harness wiring circuits “Passsenger
Pretensioner High” and “Passenger Pretensioner Low”,
and connector terminal contact is above a specified
value. This test is run once each ignition cycle during
the “Resistance Measurement Test” when:
1.
No “higher priority faults” are detected during “Turn–
ON”,
2.
“Ignition 1” voltage is in the specified value.

Action Taken
SRS control unit turns “ON” the “AIR BAG” warning
lamp and sets a diagnostic trouble code.

DTC Will Clear When
The ignition switch is turned “OFF.”

DTC Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
2.
This test determines whether the malfunction is in
the SRS control unit.
3.
This test verifies connection of the yellow connector.
4.
This test cheeks for proper operation of the shorting
clip in the yellow connector.
5.
The test checks for a malfunction passenge
r
pretensioner assembly.
6.
This test determines whether the malfunctioning is
due to shortening in the wiring.
Diagnostic Aids
An intermittent condition is likely to be caused by a short
between circuits “Passenger Pretensioner High” and
“Passenger Pretensioner Low” or a malfunctioning
shorting clip on the passenger pretensioner assembly
which would require replacement of the pretensioner
assembly. The test for this diagnostic trouble code is
only run while “AIR BAG” warning lamp is performing
the bulb check. When a scan tool “Clear Codes”
command is issued and the malfunction is still present,
the DTC will not reappear until the next ignition cycle.

RESTRAINT CONTROL 9A1-43

DTC B0057 (Flash Code 57) Passenger Pretensioner Squib Circuit Low Resistance

Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2 Repeat the “SRS
Diagnostic System
Check”
2

1. Check the passenger pretensioner squib circuit for short to
valtage or short to ground.

2. If the broblem found, repair as necessary.
Was a problem found? Verify repair Go to Step 3
3

1. Ignition switch “Off.”

2. Make sure the passenger air bag assembly yellow connector
located at the base of the passenger seat.
Is the yellow connector connected properly? Go to Step 4 Seat passenger
pretensioner
assembly yellow
connector
properly.
Go to Step 7
4

1. Disconnect and inspect the passenger air bag assembly
yellow connector located at the base of the passenger seat.

2. If ok, reconnect the passenger air bag assembly connector.

3. Ignition switch “ON.”
Is DTC B0057 Current? Go to Step 5 Go to Step 7
5

1. Ignition switch “Off.”

2. Disconnect SRS coil and passenger pretensioner assembly,
yellow connector located at the base of the passenger seat.

3. Connect 5-8840-2421-0 SRS driver/passenger load tool and
appropriate adapters to passenger pretensioner assembly
harness connectors.

4. Ignition switch “ON.”
Is DTC B0057 current? Go to Step 6 Ignition switch
“Off.”
Replace the
passenger
pretensioner
assembly.
Go to Step 7
6

1. Ignition switch “Off.”

2. There has been a decrease in the total circuit resistance of
the passenger inflator deployment loop.
3. Use the high resolution ohmmeter mode of the DVM while
checking circuits “Passenger pretensioner High” and
“Passenger Pretensioner Low”, and SRS control unit
connector terminal “44” and “43” to locate the root cause.
Was a fault found? Replace SRS
harness or repair
chassis harness.
Go to Step 7 Go to Chart A
7

1. Reconnect all components, ensure all component are
properly mounted.

2. Clear diagnostic trouble codes.
Was this step finished? Repeat the “SRS
Diagnostic System
Check” Go to Step 7

9A1-44 RESTRAINT CONTROL SYSTEM

DTC B0058 (Flash Code 58) Passenger Pretensioner Squib Circuit High
Resistance


RTW49JLF000101

Circuit Description
When the ignition switch is turned “ON”, the SRS
control unit will perform tests to diagnose critical
malfunctions within itself. Upon passing these tests
“Ignition 1”, and deployment loop voltages are
measured to ensure they are within their respective
normal voltage ranges. The SRS control unit then
proceeds with the “Resistance Measurement Test”.
“Passenger Pretensioner Low” terminal “43” is
grounded through a resister and the passenger current
source connected to “Passenger Pretensioner High”
terminal “44” allows a known amount of current to flow.
By monitoring the voltage difference between
“Passenger Pretensioner High” and “Passenger
Pretensioner Low” the SRS control unit calculates the
combined resistance of the passenger pretensione
r
assembly, harness wiring circuits “Passenger
Pretensioner High” and “Passenger Pretensioner Low”
connector terminal contact.