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RESTRAINT CONTROL 9A1-59
DTC B0670 (Flash Code 63) Airbag Telltale Circuit Malfunction
RTW49JLF000101
Circuit Description
When the ignition switch is turned “ON”, battery voltage
is applied to the “AIR BAG” warning lamp and to the
“Ignition 1” input terminal “35”. The SRS control unit
responds by flashing the “AIR BAG” warning lamp
seven times. The SRS control unit monitors the lamp
driver output by comparing the output state at “SRS
Warning Lamp” terminal “39” to the microprocesso
r
commanded state. When “Ignition 1” is in the specified
value, and the output state does not match the
commanded state of the lamp driver for 500
milliseconds, DTC B0670 is set.
DTC Will Set When
“Ignition 1” voltage is in the specified value and the
output state at the “SRS Warning Lamp” terminal does
not match the commanded state of the lamp driver for
500 milliseconds. This test is run every 100
milliseconds during “Continuous Monitoring” tests and
once per each ignition cycle at the beginning.
Action Taken
SRS control unit attempts to turn “ON” the “AIR BAG”
warning lamp and sets a diagnostic trouble code.
DTC Will Clear When
The ignition switch is turned “OFF.”
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9A1-60 RESTRAINT CONTROL SYSTEM
DTC Chart Test Description
Refer to Charts B and C to diagnose warning lamp
circuit malfunctions.
DTC B0670 (Flash Code 63) Airbag Telltale Circuit Malfunction
Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2 Go to the “SRS
Diagnostic System
Check”
2
1. Malfunctions within the “AIR BAG” warning lamp circuitry will
set this diagnostic trouble code.
2. These malfunctions are addressed in the “SRS Diagnostic
System Check” via Chart B and Chart C.
3. Failure to properly perform the “SRS Diagnostic System
Check” may result in misdiagnosis.
4. Ignition switch “ON.”
5. Clear SRS diagnostic trouble codes.
Is DTC B0670 set? Ignition switch
“OFF.”
Go to Chart A Repeat the “SRS
Diagnostic System
Check”
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RESTRAINT CONTROL 9A1-61
DTC B1000 (Flash Code 72) SDM Internal Fault (SDM=SRS control unit)
RTW49JLF000101
Circuit Description
DTC B1000 is an indication of a potential internal SRS
control unit malfunction and will set if any of the
following conditions are detected:
1) Microprocessor energy reverse time failure.
2) EEPROM read / write failure.
3) ROM check sum.
4) Calibration check sum fault.
5) Inflators reserve voltage low.
6) Inflators electronic sensor active signal not detected
during commanded deployment.
7) QSDD (High-side/Low-side) FET failure.
8) Frontal accelerometer failure.
9) Phase lock loop lost lock.
10) QSDD communication fault.
DTC Will Set When
Any of the above indicated malfunctions are detected by
the SRS control unit. The malfunctions described
above are tested mainly during “Continuous Monitoring”
and some ones run each ignition cycle.
Action Taken
SRS control unit turns “ON” the “AIR BAG” warning
lamp and sets a diagnostic trouble code.
DTC Will Clear When
SRS control unit is replaced.
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9A1-62 RESTRAINT CONTROL SYSTEM
DTC B1000 (Flash Code 72) SDM Internal Fault (SDM=SRS control unit)
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.
CAUTION: If DTC B1000 can not clear by Tech2, it is necessary to replace the SRS control unit.
Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Ignition switch
“OFF.”
Replace SRS
control unit.
Repeat the “SRS
Diagnostic System
Check” Go to the “SRS
Diagnostic System
Check”
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WORKSHOP MANUAL
TF SERIES
AXLE
SECTION 4
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