ECU GEELY FC 2008 User Guide

Supplemental restraint system--Note
Special tools and measurers which any safety airbag repairing position should have:
Changeable subassembly which safety airbag repairing position should have:
a. Safety airbag assembly at the side of driver;
b. Safety airbag assembly at the side of passanger;
c. Helix cable assembly.
d. ECU assembly;
e. Steering wheel.
I. Safety airbag joint
No. ItemApplicable
(1) Terminal dual-locking organization
(2) Airbag anti-explosive organizationJoint 3, 4, 7, 8
(3) Checking organization of electric circuit connection
(4) Inadequacy connection protection organization Joint 4
(5) Joint dual-locking organization Joint 2
(6) Joint dual-locking organizationJoint 6, 7, 10
Safety airbag at the
side of passengerSafety airbag at
the side of driver
Helix
cable
Airbag controller
1. All safety airbag joints should be yellow to be easy to distinguish the joints on other automobile parts,
this could guarantee the safety performance and reliability of safety airbag joint, each kind of joint has
special function and design.
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Number
a
b
c
d
eFunction
Disassemble airbag subassembly on steering wheel
Assemble and disassemble big nut on steering column
Assemble and disassemble ECU and safety airbag assembly
at the side of passenger on automobile body.
Used for electric measurement on wiring harness
Used for resistance measurement of electric ignition device
of airbag subassembly. Name and type of tool
5S hexagon wrench
Socket wrench 18S
14S socket wrench
Numeric multi-meter DT 992 type
Electric detonator tester
QJ992 type
Short
wiring
harness

IV. Assemble ECU joint
Figure 1 Figure 2 Figure 3
1. Press down limit switch in figure 1.
2. Dial white switch along the black line in figure 2, dial it to bottom liking that shown in figure3.
Hint: you will hear the assembling sound that shows it is put to position when white switch is
put into position.
V. Connect airbag wiring harness and short wiring harness at the side of passenger.
2. Confirm inserting it until locking, after assemble, pull it to check whether it is locked (when locking,
confirm exterior joint returns to former position, at the same time, assembling sound could hear).
Hint:
zWhen moving the sliding block, do not contact it.
zPay attention to do not distort the release board, if release board is distorted, it is neces-
sary to change it with new helix cable.
Figure 3 Figure 4
1. Insert the connector in figure 3 in the part in figure, after assemble it into its position, you will hear hint
sound.
Supplemental restraint system--Note
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Sliding blockSliding block
Limit switch

2. Inspection for indicating light of safety airbag
(1) When set the ignition switch at ON position, confirm whether the indicating light illuminates.
(2) After illuminating for five seconds, confirm whether indicating light extinguishes forever.
(3) If starting ignition switch for five seconds, indicating light does not extinguish (flash or illuminate for long
time), confirm the position of system malfunction with special diagnostic tool according to the flash
situation of indicating light.
3. System diagnosis
Safety airbag controller (KD4.1) will implement a series of cycle diagnostic testing to check whether the
function of airbag system has been prepared completely. This test will prevent restraint system from
exploding wrongly and insure the necessary explosion in impact. If finding any malfunction, safety airbag
controller (KD4.1) will store a applicable malfunction code and turn on indicating light to indicate a mal-
function state to be easy to maintain.
4. Malfunction judgment
(1) Malfunction category
System malfunction could be divided into three categories: power supply malfunction, subassembly
assembling malfunction and ECU inner malfunction.
a. Power supply malfunction
Normal working voltage of ECU is 9-18 V, related working voltage is 12 V. When automobile key is
turned to ACC gear, ECU connects power and begins to self-check, indicating light extinguishes
after illuminating for five seconds, this shows there is not any malfunction in ECU and exterior
subassembly, they could work normally. When automobile power voltage is less than 9V or higher
than 18V, ECU will self-check again. If self-checking could pass, ECU works normally, and indicat-
ing light extinguishes; if self-checking could not pass, it is necessary to self-check again, this self-
checking could be made six times, if indicating light illuminates all the time after six times, there is
some malfunction in power supply.
b. Assembling malfunction of airbag subassembly
Assembling malfunction of airbag subassembly is that malfunction which only needs to change or
repair airbag subassembly without needing to change ECU, including the situation that airbag
subassembly is not connected completely. If happening this malfunction when connecting power
supply, indicating light will flash N times at first, then it will illuminate all the time until malfunction is
removed. If happening impact in malfunction term, ECU could explode the channel of good part
and record every malfunction when exploding.
c. Inner malfunction of controller
Inner malfunction is the malfunction happening in ECU body, when happening this malfunction,
ECU could not explode airbag, and will record the impacting acceleration.
Note: common repairer could not repair this inner malfunction, if happening this malfunction,
it is necessary to change ECU.
(2) Malfunction state display
Malfunction treatment
1. Basic procedure of malfunction diagnosis
zAfter assembling new electronic control unit of safety airbag system, indicating light of safety airbag
system will extinguish forever after flashing for 5 seconds when ignition switch is at state of ON, this
shows airbag system works normally. At this time, the system does not need to repair, it is necessary
to make system diagnosis and repair when showing any situation except this.
zIf indicating light of safety airbag system does not illuminate when ignition switch is at the state of ON,
check the related circuits of indicating light, then operate it to make it enter working state.
Supplemental restraint system--Malfunction treatment
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Warning light illuminate Scanning ECU by connecting Find the malfunction Deal with Clean the code
and does not extinguish diagnostic instrument malfunction

Malfunction display of SRS could confirm originally by the flash of indicating light, detailed information
could be gained by malfunction diagnostic tool.
a. Safety airbag indicating light is driven by ECU, all malfunction displays are finished by ECU. After
working voltage is supplied for safety airbag controller (KD4.1) by battery, safety airbag controller
(KD4.1) illuminates indicating light to check SRS. To notify driver that there are some malfunctions
in system, indicating light will illuminate for long time after working voltage is supplied. If existing
SRS does not have any malfunction, indicating light will close after illuminating for five seconds
after ignition on. In original phase, safety airbag controller (KD4.1) does not prepare to check the
impact and stop the unfold until the wire of safety airbag controller (KD4.1) is reliable.
After ignition switch is turned to “ON” gear, the display type of indicating light when there is no any
malfunction in SRS is:
Assembling malfunction information of subassembly could see follow table 1.
Table1: Assembling malfunction information indicating table for airbag subassembly
Schematic drawing for slow flash indicating light
Supplemental restraint system--Malfunction treatment
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Ignition switch “ON”
Illuminate
Extinguish NumberMalfunction type
Slow flash times (N times)Remark
1Igniter at the side of driver happens short circuit3
2Igniter at the side of driver happens open circuit4
3Igniter at the side of driver connects grounding5
4Igniter at the side of driver connects battery6
5
Igniter at the side of passenger happens short circuit7
6
Igniter at the side of passenger happens open circuit8
7
Igniter at the side of passenger connects grounding9
8Igniter at the side of passenger connects battery10
9
Safety belt at the side of driver happens pre-tightening malfunction11
10
Safety belt at the side of passenger happens pre-tightening malfunction12
12Impact output interface happens malfunction
or wrong explosion
of airbag subas-
sembly will make
big hurt for human,
its warning rea-
sons should be di-
vided detailedly.

Inner malfunction information could see following table 2.
Table 2: ECU inner malfunction information indicating table
Schematic drawing for fast flash indicating light
Schematic drawing for “short, short, long and short” malfunction
If happening the situations above, it is necessary to turn off key switch of automobile at first, then turn on key
switch and start it again, if information hint could not be removed, it is necessary to change ECU.Supplemental restraint system--Malfunction treatment 246 NumberMalfunction typeFast flash typeRemark
1Electronic acceleration offset malfunctionShort, short, short and long0001
2Electronic acceleration self-checking malfunctionShort, short, long and short0010
3SCM inner RAM is wrongShort, short, long and long0011
4Inner parameter is wrongShort, long, short and short0100
5Inner malfunction or acceleration storage space is full and ignition record has been made. Short, long, short and long0101
6Mechanical safety sensor happens malfunctionShort, long, long and short0110
7Increased pressure is wrongShort, long, long and long0111
8Ignition driving function is wrongLong, short, short and short1000
9Voltage of ignition voltage F12 and F13 is wrongLong, short, short and long1001
10Other parts are wrongLong, short, long and short1010

cthere are some malfunctions, indicating light will indicate them. If exterior malfunctions are historical,
after they are removed, indicate will disappear.
done displayed or historical malfunction is only set up again by server. Inner malfunction or “impact
record” of safety airbag controller (KD4.1) could not be set up again, in this situation, it is necessary to
change safety airbag controller (KD4.1).
(3) micro controller, independent indicating light illuminates.
Microprocessor having obvious malfunction state could not work, so it could not control the work of indicat-
ing light. In this situation, indicating light will illuminate directly by applicable circuit without considering the
micro-processor, liking that shown in following:
zThe battery providing electricity for safety airbag controller (KD4.1) disables: indicating light illumi-
nates by the automatic light driving function.
zInner working voltage loses: indicating light illuminates usually.
zNew setup caused by the unsuccessful watchdog trigger: indicating light flashes
zMicro-processor does not work: indicating light illuminates usually
zInsert of connecter of safety airbag controller (KD4.1) is wrong: indicating light illuminates usually by
short circuit stick.
Take example to specify diagnostic step:
If finding indicating light of safety airbag illuminates usually, even if it extinguishes at last, you could check
by follow step. First is to check the part happening malfunction with diagnostic tool.
Then make by the checking step for corresponding position.
a. If scan result is inner malfunction or safety airbag has exploded, at this time, change the ECU directly.
b. Malfunction has been removed.
Supplemental restraint system--Repair
 248 

Supplemental restraint system--Remove malfunction
Remove malfunction
Malfunction table
lThe voltage disappears (fuse is cut off)
l Combination instrument happens malfunction
lWiring harness between instrument package
and ECU unit has malfunction Malfunction Test statePossible reason
Indicating light of
safety airbag
system does not
illuminateWarning circuit of safety
airbag system happens
malfunction
1. Indicating light of safety airbag system does not illuminate
Diagnostic procedure
When making first malfunction test, we advise shaking wiring harness and plug to test whether there is
discontinuous bad contact in wire, if having this problem, please verify whether the connection of plug, terminal
and wiring harness is correct and is not damaged, if it is not this problem, please make by next step.
(1) Check other wiring harnesses and indicating lights of instrument package
a. Set ignition switch at ON position,
b. Are other warning indicating lights illuminating?
If illuminating: set ignition switch on LOCK position, then make next operation.
If not: check the power supply system and grounding system of instrument package (fuse), then
make step 5.
(2) Check the bulb
Warning: wrong treatment for safety airbag system parts will incur safety airbag and pre-
tension safety belt are opened accidentally, this might happen heavy accident. Please read
service warning of safety airbag system before disposing safety airbag parts.
a. Set ignition switch at LOCK position,
b. Cut off cathode wire of battery and keep this state for 60 seconds at least,
c . Disassemble combination instrument,
d. Measure whether corresponding two pins of indicating light of safety airbag could conduct,
Yes: make next step,
No: change the bulb of indicating light.
(3) Check the wiring harness connection between ECU unit and instrument package .
a. Set ignition switch at LOCK position,
b. Cut off cathode wire of battery,
c . Cut off the plug of instrument package ,
d. Check whether corresponding circuit of indicating light could conduct,
Yes: make next step,
No: change the wiring harness, then make step 5.
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Number Malfunction removing itemSpecification
1 Indicating light of safety airbag system does not illuminate Warning circuit of safety airbag system happens malfunction
2 Indicating light of safety airbag system illuminates usually Warning circuit of safety airbag system happens malfunction or
there is exterior malfunction

Supplemental restraint system--Remove malfunction
Diagnostic procedure
When starting to check, firstly, use special diagnostic tool and ECU to make diagnostic communication to
find the reason of malfunction, if communication could not implement, make following inspection:
(1) Check the battery
a. Measure the voltage of battery
b. Is the voltage higher than 9V?
Yes: make next operation,
No: Power supply of battery is lack, check the charging/discharging system, then make step 5.
(2) Check the conduction of wiring harness between ECU and combination meter.
a. Set ignition switch at LOCK position,
b. Cut off cathode of battery,
c. Open the defending board of central channel,
d. Disconnect the connector of instrument package ,
e. Connect the cathode of battery,
f. Set ignition switch at ON position,
g. Check whether the terminal voltage of corresponding connector of instrument is 12V (connecting
wire of power supply and instrument)
Yes: make next step,
No: check the circuit part, then make step 5 after repairing it.
h. Set ignition switch at LOCK position,
i. Check whether the corresponding terminal of instrument connector conducts with corresponding
terminal of diagnostic interface (diagnose two ends of K wire),
Yes: make next step,
No: repair or change the wiring harness, then make step 5.
j. Guarantee cathode of battery is cut off and keep this state for one minutes at least, cut off connec-
tor of ECU.
k . Disconnect the plug of instrument package,
l. Check whether it conducts between ECU plug voltage, K wire, airbag indicating light terminal and
plug of instrument package ?
Yes: make next operation,
No: change the wiring harness, then make the step 5.
m. Disassemble the ECU to check whether the terminal is good, and the short circuit stick is broken.
Yes: change the ECU,
No: connect the ECU connector again, then make next operation.
zPower supply of battery is lack
zECU has inner malfunction
zIndicating light of combination meter safety airbag has
malfunction
zPlug connection of ECU has malfunction
zPlug of combination meter contacts badly
zPower supply fuse of ECU is cut off or contacts badly
zPlug terminal of ECU contacts badly
zWiring harness between plug terminal and grounding of
ECU contacts badly
zSafety airbag circuit at the side of driver or passenger
has malfunction. Malfunction Test statePossible reason
Indicating light of
safety airbag sys-
tem illuminates
usuallyIndicating light of safety
airbag system illumi-
nates usually
2. Indicating light of safety airbag system illuminates usually
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(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 conditionWarning
zTest 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.
zInner 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 conditionWarning
zTest 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.
zThe voltage of safety airbag system unit and the grounding connector pin is less than
9V.
Possible reasonzThe 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
Supplemental restraint system--Remove malfunction
 253 
Possible reason
OperationInner 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.

Diagnosis of impacted automobile
No matter whether the safety airbag has been unfolded, the inspection and maintenance for impacted auto-
mobile should be made by following sequence.
1. Check the ECU diagnostic signal.
(1) Connect the diagnostic joint of diagnostic tool,
(2) Use diagnostic tool to read the diagnostic result.
2. Repair sequence
Note: For the impact, when power supply of battery is lack, diagnostic tool could not communicate
with ECU, at this time, it is necessary to check and maintain the wiring harness of panel or use
exterior power supply.
(1) When safety airbag has been unfolded,
Following parts should be changed with new ones
a. Safety airbag assembly at the side of passenger
b. ECU
c. Safety airbag assembly at the side of driver
d. Pre-tension safety belt at the side of driver and passenger
Check the following parts, if they are abnormal, change them with new ones
a. Helix cable
b. Steering wheel, steering column, combination switch
Assembling state for steering wheel of safety airbag assembly at the side of driver
a. Check whether there is any abnormal noise in steering wheel, its action is flexible and clearance is
normal.
b. Check whether the joint of wiring harness is damaged or terminal is distorted.
Supplemental restraint system--Remove malfunction
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