(3) Confirm the malfunction will not happen again after repairing,

a. Set ignition switch at LOCK position,
b. Cut off cathode of battery, and keep this state for one minutes at least,
c. Connect all ECU plugs,
d. Connect the subassembly plug of safety airbag at the side of driver,
e. Connect the subassembly plug of safety airbag at the side of passenger,
f. Connect the plug of pre-tension safety belt at the side of driver and passenger,
g. Connect the plug of helix cable,
h. Connect the cathode of battery,
i. Set ignition switch at ON position,
j. Does the indicating light of safety airbag work correctly?

Yes: malfunction has been removed, and the repair procedure should be explained for customers,
No: Check the malfunction state again, then if malfunction happens again, repeat from step 1.

3. Inner malfunction

Inner malfunction of safety airbag system unit

Test condition

Warning

Test condition for this malfunction is the malfunction code which does not happen

before checking, DTC makes the inspection, it might incur wrong operation to hurt

human or system when making this inspection, so it is necessary to make preparation

before the inspection.

Inner circuit of electronic control unit of safety airbag system has malfunction.

Power voltage of electronic control unit of safety airbag system is too low.

Test condition

Warning

Test condition for this malfunction is the malfunction code which does not happen

before checking, DTC makes the inspection, it might incur wrong operation to hurt

human or system when making this inspection, so it is necessary to make preparation

before the inspection.

The voltage of safety airbag system unit and the grounding connector pin is less than

9V.

Possible reason

The voltage of battery is too low.

The wiring harness between battery and electronic control unit of safety airbag system

has malfunction.

4. Malfunction of power supply

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Possible reason

Operation

Inner malfunction in safety airbag system unit

Change the safety airbag system unit, referring to the disassembling and assembling of

safety airbag system and safety airbag system unit.

Diagnostic procedure

(1) Check the battery

Is the voltage higher than 9V?
Yes: make next operation,
No: The voltage of battery is too low, check the charging/discharging system.
Refer to chapter 1, Inspection of battery,  charging system

(2) Check the wiring harness between battery and safety boox.

Disassemble fuse panel to set ignition switch at ON position without loosening connector.
Measure whether the voltage of related two pins of fuse panel is more than 9V?
Yes: make next step
No: check and repair the wiring harness.

(3) Check the wiring harness between fuse panel and the connector of safety airbag system unit.

Warning:
If the treatment is wrong, safety airbag assembly might be triggered to unfold to make heavy
human hurt, so, before the treatment, it is necessary to read repairing warnings carefully.
Refer to repairing warning of safety airbag system.
a. Set ignition switch at LOCK position,
b. Loosen the cathode cable of battery and keep this state for one minute at least,
c. Disassemble the shell body of steering column,
d. Loosen the connector of helix cable,
e. Disassemble glove box (with safety airbag assembly at the side of passenger),
f. Loosen the connector of safety airbag assembly at the side of passenger,
g. Disassemble left inner trim board,
h. Loosen the connectors of all safety airbag system units,
i. Assemble cathode cable of battery, and set the ignition switch at ON position, then measure

whether the voltage of safety airbag system unit and grounding connector pin is more than 9V?
Yes: make next step,
No: change the wiring harness.

j. Set the ignition switch at LOCK position,

Loosen the cathode cable of battery and keep this for one minute at least.

k. Disassemble left inner trim board,
l. Cut off the conversion connector of safety airbag system unit,
m. Assemble cathode cable of battery, and set the ignition switch at ON position, then measure

whether the voltage of safety airbag system unit and grounding connector pin is more than 9V?
Yes: malfunction diagnosis ends,
No: change the wiring harness.

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5. Malfunction at the side of driver

Malfunction of safety airbag at the side of driver (resistance is too big or too small,

short circuit, grounding and so on)

Test condition

Warning

If the treatment is wrong, safety airbag assembly might be triggered to unfold to make

heavy human hurt, so, before the treatment, it is necessary to read repairing warnings

carefully. Refer to repairing warning of safety airbag system.

The resistance between connector pins of safety airbag system unit is not in regulated

scope.

Related wiring harness of driver airbag in safety airbag system happens short circuit or

open circuit.

Possible reason

Safety airbag assembly at the side of driver has malfunction.

Helix cable has inner malfunction.

Connector of the circuit between helix cable and electronic control unit of safety airbag

system has malfunction.

Wiring harness between helix cable and electronic control unit of safety airbag system

happens open circuit or short circuit.

Connector of driver gas generator in safety airbag system is not inserted well.

Diagnostic procedure

(1) Check helix cable

Warning
If the treatment is wrong, safety airbag assembly might be triggered to unfold to make heavy
human hurt, so, before the treatment, it is necessary to read repairing warnings carefully.
Refer to repairing warning of safety airbag system.

Is every related part of helix cable normal? (Whether the relationship between pins is normal,
whether there is any unnecessary short circuit, open circuit and other phenomenon)
Normal: make next step
Abnormal: change the helix cable
Refer to safety airbag system, disassembling and assembling of helix cable

(2) Confirm whether the malfunction is on safety airbag assembly at the side of driver or other parts.

a. Change it with a good safety airbag assembly at the side of driver,
b. Assemble the cathode cable of battery,
c. Set ignition switch at ON position,
d. Is there the display of malfunction code? Could it be removed?

Yes: change the safety airbag assembly at the side of driver

Refer to safety airbag system, disassembling and assembling of safety airbag assembly at
the side of driver.

No: make next step

(3) Check the connector of helix cable wiring harness

a. Set ignition switch at LOCK position.
b. Loosen the cathode cable of battery and keep this state for one minute at least,
c. Disassemble shell body of steering column,
d. Loosen connector of helix cable,
e. Is the connector of helix cable normal? (Whether the relationship between pins is normal, whether

there is any unnecessary short circuit, open circuit and other phenomenon)
Normal: make next step
Abnormal: change the helix cable
Refer to safety airbag system, disassembling and assembling of helix cable

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(4) Check the wiring harness between helix cable and electronic control unit of safety airbag system

a. Set ignition switch at LOCK position,
b. Loosen the cathode cable of battery and keep this state for one minute at least,
c. Disassemble glove box (with safety airbag assembly at the side of passenger),
d. Loosen the connector of safety airbag assembly at the side of passenger,
e. Disassemble left inner trim board,
f. Loosen the connectors of all safety airbag system units,
g. Check the wiring harness between connector pole of safety airbag system unit and helix cable

connector pin.The wiring harness between safety airbag system at the side of passenger unit con-
nector pin and helix cable connector pin has following situation:

Earth
Short connection with power supply
Short circuit

h. Are the wiring harnesses above normal?
i. Normal: malfunction diagnosis ends, assemble all parts
j. Abnormal: change the wiring harness.

6. Malfunction at the side of passenger

Diagnostic procedure

(1) Check the connector of safety airbag assembly at the side of passenger

If the treatment is wrong, safety airbag assembly and pre-tension safety belt might be triggered to
unfold to make heavy human hurt, so, before the treatment, it is necessary to read repairing
warnings carefully.
Refer to repairing warning of safety airbag system.

Malfunction of safety airbag at the side of passenger (resistance is too big or too

small, short circuit, grounding and so on)

Test condition

Warning

If the treatment is wrong, safety airbag assembly and pre-tension safety belt might be

triggered to unfold to make heavy human hurt, so, before the treatment, it is necessary

to read repairing warnings carefully. Refer to repairing warning of safety airbag system.

The resistance between connector pin 13 and pin 14 of safety airbag system unit is not

in regulated scope.

The wiring harness between connector pin 13 and pin 14 of safety airbag system unit

happens short circuit.

Possible reason

Safety airbag assembly at the side of passenger has malfunction.

Connector between safety airbag assembly at the side of passenger and electronic con-

trol unit of safety airbag system has malfunction.

Connector between safety airbag system unit and grounding position has malfunction.

The circuit between safety airbag assembly at the side of passenger and electronic

control unit of safety airbag system happens open circuit or short circuit.

Circuit between safety airbag system unit and grounding position happens open circuit

or short circuit.

Safety airbag system unit has malfunction.

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