light GREAT WALL HOVER 2006 Service Owner's Guide
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Safety airbag-8
Internal failure determined by SRS-ECU
Serial
No. List of failure Description of failure
1 Micro-controller AD converter or EEPROM is faulty (the micro controller will be reset
and alarm lamp is light when the RAM has failure.)
2 Driver’s front airbag ignition loop Enable the failure
Measure the failure of loop
3 Passenger front airbag ignition loop
(if realized) Enable the failure
Measure the failure of loop
4 Seat safety belt preloaded ignition loop
(if realized) Enable the failure
Measure the failure of loop
5 Passenger side safety belt preloaded
ignition loop (if realized) Enable the failure
Measure the failure of loop
6 Driver’s side airbag ignition loop
(if realized) Enable the failure
Measure the failure of loop
7 Passenger side airbag ignition loop
(if realized ) Enable the failure
Measure the failure of loop
8 Maximum times of explosion of safet y
belt pre-tightener Reach the maximum value 6
9 Holding time of ECU ener gy
(self-supply time) Too short
10 Accelerometer Deviation range
Sensor not in constant, stable model
Sensor tests the failure itself
11 The measurement of ignition loop is
rejected continuously No cycling diagnosis test (duplicated calculation)
12 Safety sensor Calculate the safety sensor open-loop using the method that power-off
for 2 or more than 2 seconds is considered as passing
13 Initial firing current All initial firing current in normal status when the front airbag releases.
14 The ignition of side airbag is not
determined. Though SRS-ECU has received ignition information for 5 times during
HSIS cycling ignition, the ignition can not be determined due to the side
safety..
Debug the failure codes
Approach 1. The failure codes will be debugged following the ECU’s receipt from the X-431 diagnostic tester of the debugging
failure codes order through the serial interface, however, if an internal failure code is recorded or one impact is
recorded, the debugging will not be executed.
Approach 2. Ground 488# line for 5 times in 10 seconds to debug the failure codes.
Failure status display (alarm lamp keeps illuminating).
1. Bulb test
SRS-ECU will light the alarm lamp in order to test the bulb after working voltage is provided to it through the battery. The lamp
will flash for 6 times and then extinguish at 1HZ in the initial phase. The alarm lamp will keep illuminating after the working
voltage is provided in order to inform the driver’s system failures. The alarm lamp will keep illuminating for 6 seconds after the
ignition on and then be extinguished if the history-accumulated failures are less than five times. In the initial phase, SRS-ECU will
not prepare to test impact and stop release till the circuit is stable. Therefore, alarm lamp’s display manner will be one of
following projects in the initial phase. (Table 4.9).
Project 1. If the impact is recorded or the number of history accumulated failures is or more than 5,the alarm lamp will keep
illuminating, simultaneously, it will also keep illuminating if there is a possible explosion failure.
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Safety airbag-9
Project 3 functional working (neither possible explosion failure or historical failure).
Table 4.9 indicator lamp’s activities after ignition
2.Failure indication
The alarm lamp will indicate it in case any failure arises. If the external failure is a historical one, the indication will be called off. If
the number of history-accumulated failures is or more than 5, the alarm lamp will keep illuminating albeit no failure emerges. The
case of low power will be excluded.
A displayed or historical failure can but only be reconfigured by the service personnel. An internal failure or impact record can not
be reconfigured, in these cases, SRS-ECU must be replaced.
3.Micro controller-independent alarm lamp illumination
The micro-controller in clear failure status can not work therefore can not control the alarm lamp. In this case, the alarm lamp
will be directly lighted via suitable circuit despite of the micro-controller. As following,
The battery for SRS-ECU fails, the alarm lamp will be continuously lighted through the lamp drive function.
b. No internal working voltage, the alarm lamp keeps illuminating
c. Reconfiguration caused by watchdog’s trigging failure, the alarm lamp flashes.
d. No work of micro-controller, the alarm lamp keeps illuminating
e. Incomplete plugging-in of SRS-ECU connector, the alarm lamp keeps illuminating via shoring bar Next explain the diagnostic
procedure by taking some examples
If the alarm lamp is found keeping illuminating, please test it according to the following procedure even it extinguishes finally.
First test the failure region with the scanner followed by the test in the failure region with the corresponding approaches and
steps.
a If an internal failure or the explosion of safety airbag is scanned, replace the SRS-ECU
b.Troubleshooting Project 2. The number of history- accumulated failures is or more than one and less than 5. (The case of low power is excluded)
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1. Extinguishments of safety airbag system alarm lamp
Troubleshooting
Extinguishments or normal-light of alarm lamp
NO . Troubleshooting item Description
1 T he warning la mp of safety a irbag
system is not displayed. Safety airbag system warns circuit failure
2 T he warning la mp of safety a irbag
system is light normally. Safety airbag system warns circuit failure or external
failure.
1 Extinguishments of safety airbag system alarm lamp
Test status Safety airbag system warns circuit failure.
Possible causes No voltage (fuse shutoff)
Combined instrument failure
Failure of wiring harness between instrument cluster and ECU unit
Diagnostic procedure
When first carry out failure test, joggle the wiring harness and plug to test whether there is periodical bad contact in the circuit, if
it so, please confirm whether the plug, terminal and wiring harness well connected and in good condition. If it is not any of previous
cases, operate according to the following steps.
Procedure Te s t Operation
Ye s Place the ignition switch in LOCK
position followed by next step
1 Test other wiring harness and instrument cluster
indicator lamp
·place the ignition switch in ON position
·light other alarm and indicator lamps No Test the instrument cluster power-supply
system and grounding s ystem (fuse), then
go to step 5.
Yes Next step
2 Bulb test
Warning:
Incorrect handling with the safety airbag system
units will cause the safety airbag’s improper
release and pretension of safety belt, which will
lead to serene accidents. Please read safety airbag
service warning before handling the safety airbag
units.
·Place the ignition switch in LOCK position。
·shut off accumulator negative line and keep the
status for at least 60 seconds.
·Remove the combined instrument.
Test the connection between the two
corresponding stitches of safety airbag alarm lamp No
Rep la ce th e b ulb of a larm la mp.
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2. Normal-light of safety airbag system indicator lamp
2 Normal-light of safety airbag system alarm lamp
Test status Normal-light of safety airbag system alarm lamp
Possible causes Insufficient battery voltage
ECU internal failure
Combined instrument safety airbag alarm lamp failure
ECU plug misconnects
Combined instrument plug bad-contact
ECU power-supply fuse shutoff or bad contact
Misconnection of ECU plug terminal
Bad contact between ECU plug terminal and grounding wiring
harness.
Driver ’s or passengers’ side safety airbag circuit failure.
Procedure Te s t Operation
Yes Next procedure.
3 Test the wiring harness connection between ECU
unit and instrument cluster.
·Place the ignition switch in LOCK position。
·shut off accumulator negative line
·shut off the instrument cluster plug
·test the connection b etween alarm lamp circuit
and its relative circuits No Replace the wiring harness and get into
step 5
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Do the troubleshooting if the alarm lamp re-illuminates after its extinguishments following the 6-second-flashing (or it keeps
illuminating from the very beginning)
10. Test
a. Driver’s side airbag module test (Figure8-3)
Check the following items and replace the corresponding safety airbag module part with anything abnormal with a new one.
Abandon the safety airbag’s old parts after its release according to the instructed procedure.
Caution
Do not jam the clock spring wiring harness during the steering wheel and safety airbag module assembly installation.
After the installation, rotate the steering wheel to left and right positions as enough as possible to confirm whether something
abnormal is with it.
d. Post-installation test.
lightly rotate the steering wheel to the left and right to confirm whether something abnormal and noises will arise.(Driver’s side
safety airbag module, clock spring)
Place the ignition switch in ON place.
SRS alarm lamp flashes in 6 seconds and then extinguishes.
Caution
If without the clock spring central involution, the steering wheel will not be able to rotate at midway, or the clock spring
circuit will be damaged so that jeopardize SRS safety airbag’s normal activities.
The spacer must be removed after replacing a clock spring with a new one, otherwise it will damage the clock spring.
c. Steering wheel and safety airbag module assembly installation.
Install the steering wheel and safety airbag module assembly after clock spring’s central involution.
safety airbag system failure alarm lamp
Caution
The safety airbag module (squib) circuit resistance can even not be tested by the designated tester.
When testing the resistance with an experimental instrument, sometimes the improper release will be caused by the
static interference because of the current in explosion pipe and cause some major damaging accidents.
Whether depression, crack or deformation is with the shroud.
Whether the joint is broken and the terminal is deformed.
Whether depression, crack or deformation is with the gas generator shield.
Safety airbag module. Installation status.
Caution
Replace the safety airbag with depression, crack or deformation with a new one. Its old parts must be abandoned after
its release.