sensor SSANGYONG MUSSO 1998 Workshop Repair Manual

SUPPLEMENTAL RESTRAINT SYSTEM(SRS) 8B-7
DIAGNOSIS
DESCRIPTION
Air bag control unit continuously controls system function as follows during ignition ON or driving.
- Recognition of collision
- Internal diagnosis
- External diagnosis
If recognize or detect defects, warning lamp will turn on. If there is danger of improper deployment, the system will
enter overall shutdown status and the air bag will not inflate.
Air bag control unit will store detected internal and external defects in the EEPROM.
System Control
Battery Voltage Check
Battery voltage will be monitored continuously. If voltage is out of normal operating range, all system diagnosis will
stop and warning lamp turn on.
Battery Voltage (V)
< 8.7
9 - 16
> 16.3
Function
System diagnosis stops and warning lamp turns on
Normal operation range
System diagnosis stops and warning lamp turns on
Squib Diagnosis
It checks not only high (4.50.5) or low (1.40.5) resistance but also short resistance (1- 10k) status between the
battery and ground to indicate defects in squib line by blinking warning lamp. Air bag control unit (AC4) can measure
squib resistance.
Warning Lamp Turning On
Air bag control unit detects system defects during ignition ON or driving and displays following 2 warning lamps.
- Warning lamp ON: internal defects of the air bag control unit
- Warning lamp blinking: higher resistance than standard in the squib line or short at the battery or ground,
Safety Function Check
It checks defects during operation of the arming sensor If the sensor is shorted for more than 2 seconds, the module
will enter overall shutdown mode.
Temperature Sensor
Function of the temperature sensor will be monitored continuously. If there is fault due to defective sensor or short,
the lamp will turn on and program will take calibration temperature (25) of collision conditions.
Power Supply
Airbag control unit operates in 9-16v and the characteristic of the system has backup condenser to supply the power
for max.150ms if there is power defect during collision.

SUPPLEMENTAL RESTRAINT SYSTEM(SRS) 8B-9
Diagnosis
Air bag control unit diagnoses each function in the intervals of 250ms - 20 sec. during start-up or driving to prevent
unwanted air bag deployment. If there is defect, it turns on or blinks warning lamp to indicate defects in the air bag
system to the driver. And fatal defect is found, air bag control unit enters overall or partial shutdown status and fault
code will be stored.
Air bag control unit diagnoses following items.
- Ignition TR
- Acceleration
- Microprocessor, RAM and ROM
- Watchdog
- Shutdown Switch
Diagnosis Condition Diagnosis Items
Start-up (ignition ON)
During Driving
Lamp Blinking Mode
There are 2 kinds of blinking mode
1. When system internal fault is found, the lamp will stay on.
2. The lamp will blink according to external fault and there are 2 blinking codes.
Blinking code 1 (Squib resistance fault in the driver’s air bag squib line)
Blinking code 2 (Squib short on plus and minus in the air bag squib line)
Lamp blinking code is as follows. The last blinking will be within 0.5 sec. and 1 cycle of blinking will be repeated every
5 seconds.
Blinking Code 1
(Sec.) 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
Blinking Code 3
(Sec.) 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
- Squib resistance
- Squib line short to battery and ground
- Energy reserve system
- Lamp output
- Battery voltage
- ASIC communication
- Arming sensor
- ASIC overheating
- RAM and W/D
- EEPROM

8B-10 SUPPLEMENTAL RESTRAINT SYSTEM(SRS)
1. Position the ignition switch to ‘OFF’.
2. Connect the harness connector of scanner to the diagnosis
socket in engine compartment.
3. Turn the ignition switch to ‘ON’ position.
4. Select “Electronic control vehicle diagnosis” from function
selection display and press ‘Enter’.
5. Select “Musso (’98 model year)” from vehicle model
selection display and press ‘Enter’.
6. Select “Electronic air bag” from control system selection
display and press ‘Enter’.
7. Select “Self-diagnosis” from diagnosis item selection display.
Notice
Check sensor value of output display, if necessary.
8. Determine the fault code and trace defective component.
Notice
Refer to self-diagnosis list.
SELF DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM(SRS) 8B-13
Fault
CodeDefectsService HintAppli-
cation
24 Squib No. 4 resistance
X
25 Energy reserve No. 1 voltage
26 Energy reserve No. 2 voltageX
27 Energy reserve No. 3 voltageX
28 Energy reserve No. 4 voltageX
29 Energy reserve No. 5 voltage
30 Energy reserve No. 6 voltage
31 Energy reserve No. 1 current off
capacity
32 Energy reserve No. 2 current off
capacityX
33 Energy reserve No. 3 current off
capacityX
34 Energy reserve No. 4 current off
capacityX
35 Energy reserve No. 5 current off
capacity
36 Condensor voltage
37 Collision times checksum
lDriver’s squib resistance is lower than standard
(1.4±0.3W).
lCheck related circuits for open/short.
lCheck connection of connector.
lCheck the ECU.
lReplace the squib wire.
lPlus side short : 7k, ground side short : 6kW.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
4 1 Major USAlAir bag control unit internal defects.
lCheck and replace the ECU. 38 Driver’s acceleration sensor
39
Driver’s acceleration sensor off-set
40 Arming sensor
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.

8B-14 SUPPLEMENTAL RESTRAINT SYSTEM(SRS)
Fault
CodeDefectsService HintAppli-
cation
42 Over heat
4 3 SENS
44 Standard band gap
45 Temperature sensor
46 Warning lamp
47
Battery voltage
49 Fault code list
5 0 USA communication
51 LSA communication
52 No EEPROM program
53 EEPROM checksum
5 4 EEPROM map
55 External watchdog 1
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lOpen/short in the warning lamp circuit.
lCheck related circuits for open/short.
lCheck connection of connector.
lCheck the ECU.
lPower wire voltage is out of standard voltage (9
- 16V).
lCheck the battery for voltage and charging.
lCheck related circuits for open/short.
lCheck connection of connector.
lCheck the ECU.
lAir bag control unit internal defects.
lCheck the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
56 Arming sensor-no close
57 RAM check
5 8 System
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.
59 External watchdog 2
6 0 Pulse
lAir bag control unit internal defects.
lCheck and replace the ECU.
lAir bag control unit internal defects.
lCheck and replace the ECU.

SUPPLEMENTAL RESTRAINT SYSTEM(SRS) 8B-21
AIR BAG CONTROL UNIT(AC4)
Removal & Installation Procedure
AC4 is installed on the center portion of the front floor tunnel.
Built-in accelerometer sensor detects collision and determines
action or non-action and ignition time.
Notice
Do not disassemble the AC4 to repair. If defective, replace it.
AC4 should not be shocked or vibrated by dropping on the
ground or bumping.
Replace the AC4 with new after air bag inflation.
1. Disconnect the negative battery cable and wait for 30
seconds before starting service.
Notice
Though battery cable is disconnected, air bag control unit
will maintain backup power for 150ms and air bag can be
inflated, so wait for min.30 seconds.
2. Remove the console box and center fascia panel assembly.
3. Remove the heater control switch and audio assembly.
4. Remove the lower side panel of the driver’s portion and
glove box.
5. Remove the lower main panel.
6. Release the lock lever of the AC4 connector and disconnect
the connector.
7. Unscrew 3 nuts and remove the AC4.
Notice
For installation, horizontal position should be secured for
the better changes of collision pulse between the vehicle
body and air bag control unit.
8. Installation should follow the removal procedure in the
reverse order.
Inspection Procedure
1. Check AC4 case and welt bolts for crack or deformation.
2. Check connector, lock lever and terminal for deformation.
Notice
Replace the AC4 with new if dust, deformation or corrosion
found.

BODY WIRING SYSTEM 9A-9
44 Joint Connector.................................................... Ground
45 Door Unlock Switch
46 Front Fog Lamp Switch
47 Rear Defogger Switch
4 8 ECS Switch
49 Rear Fog Lamp Switch........................................Rear Fog Lamp
50 Digital Clock
51 Thermo Amplifier
52 Glove Box Lamp Switch
53 Air Conditioner Wiring Connetor
54 Glove Box Lamp
55 Ground 6
56 Ground 6.............................................................Gasoline E/G
57 Ground 7.............................................................Gasoline E/G
58 Wheel Speed Sensor (FR)..................................ABS 5.0 or ABD 5.0
59 O
2 Sensor............................................................E32 Gasoline E/G
60 Engine Main Wiring Connector............................Gasoline E/G with MSE ECU
61 HFM .....................................................................Gasoline E/G with HFM ECU
61-1 MSE .....................................................................Gasoline E/G with MSE ECU
62 Front Door Wiring Connector (Passenger Side)
63 Front door Wiring Connector (Passenger Side)
64 Joint Connector (B+)
65 Audio
66 Audio
67 Air Bag Wiring Connector
68 Chime Bell
6 9 Buzzer
70 Kick Down Switch.................................................Automatic Transmission
71 Diode 2................................................................Manual Transmission
72 Ground 3
73 Ground 4
74 Front Cigarette Lighter
75 Diode 3................................................................Automatic Transmission, MB
76 S/E Mode Selector Switch....................................Automatic Transmission
76-1Mode Switch........................................................Automatic Transmission
77 “B” Position Switch..............................................Automatic Transmission
78 “P” Position Switch..............................................Automatic Transmission
79 Shift Lock Solenoid Valve.....................................Automatic Transmission
8 0 TCCU
81 Ground 5.............................................................Gasoline E/G
81-1Ground 7.............................................................Diesel E/G
82 Seat Extension Wiring Connector
83 Transmission Extension Wiring Connector...........E23 & E32 Gasoline E/G with Manual Transmission
83-1 Transmission Extension Wiring Connector...........Diesel E/G with MB A/T
84 Transmission Extension Wiring Connector...........Gasoline E/G with Manual Transmission
84-1 Transmission Extension Wiring Connector...........Diesel E/G with Manual Transmission or BTRE A/T
85 Transmission Extension Wiring Connector...........E23 & E32 Gasoline E/G with A/T
85-1 Transmission Extension Wiring Connector...........Diesel E/G with BTRE A/T
86 Transfer Case Motor
87 Transfer Case Motor
88 Vehicle Speed Sensor
89 Fuel Gauge
90 Acceleration Sensor.............................................ABS 5.0
91 Seat Belt Switch (Passenger)
92 Seat Heater Switch
93 Head Lamp Leveling Device Switch.....................Leveling Device

9A-10 BODY WIRING SYSTEM
94 Seat Belt Switch (Driver)
95 Seat Belt Switch (Dirver)
96 Parking Brake Switch
97 Rear Cigarette Lighter
9 8 OVPR.................................................................Gasoline E/G
99 LH Side Repeater...............................................Rear Fog Lamp
100 Engine Wiring Connector
101 Engine Joint Connector
102 Engine Joint Connector......................................Gasoline E/G
103 ECS Engine Wiring Connector...........................Diesel E/G & Gasoline E/G with HFM ECU
104 ABD Engine Wiring Connector...........................ABD 5.0
105 ABD Engine Wiring Connector...........................ABD 5.0
105-1ABS Engine Wiring Connector............................ABS 5.0
106 Canister Purge Solenoid Valve...........................Gasoline E/G with MSE ECU
106-1Canister Purge Solenoid Valve...........................E20 & E23 Gasoline E/G with FHM ECU
107 Econo/Standard Solenoid Valve.........................Gasoline E/G with Automatic Transmission
108 CO Potentio Meter..............................................Gasoline E/G with HFM ECU & CO Potentio Meter
109 Front Wiper Motor
11 0 O
2 Sensor...........................................................E20 or E23 Gasoline E/G
111 RH Side Repeater
112 Engine Wiring Connector
113 Vertical Sensor
114 Lateral Sensor
115 Diagnosis
11 6 Joint Box.............................................................Gasoline E/G (E32)
117 Canister Purge Solenoid Valve...........................E32 Gasoline E/G with HFM ECU
118 Led Antenna......................................................Rolling code type Immobilizer
119 E-key Connector................................................Gasoline E/G with Rolling Code Type Immobilizer
120 Receiver Unit......................................................Gasoline E/G with Rolling Code Type Immobilizer
121 Receiver Unit......................................................Gasoline E/G with Rolling Code Type Immobilizer
122 Receiver Antenna..............................................Gasoline E/G with Rolling Code Type Immobilizer
123 Receiver Connector...........................................Gasoline E/G with Rolling Code Type Immobilizer
124 ICU Connector....................................................Gasoline E/G with Rolling Code Type Immobilizer
125 ICU .....................................................................Gasoline E/G with TOD (MSE ECU 3.2 Engine Only)
126 CAN Line............................................................Gasoline E/G with TOD (MSE ECU 3.2 Engine Only)
127 TOD ...................................................................Gasoline E/G with TOD (MSE ECU 3.2 Engine Only)
128 TOD ...................................................................Gasoline E/G with TOD (MSE ECU 3.2 Engine Only)
129 Transfer Case Speed Sensor.............................Gasoline E/G with TOD (MSE ECU 3.2 Engine Only)
130 Engine Main Wiring Connector...........................Gasoline E/G with MSE ECU
131 Remote Engine Start..........................................Diesel E/G with A/T & Black Out Lamp
132 Remote Engine Start..........................................Diesel E/G with A/T & Black Out Lamp
133 TCU ....................................................................Diesel E/G with BTRE A/T
134 TCU ....................................................................Diesel E/G with BTRE A/T
135 Ground 5............................................................Diesel E/G
136 Start Protection Relay.........................................Diesel E/G with Rolling Code Type Immobilizer
137 EGR control unit.................................................Diesel E/G
1 3 8 ICU 1..................................................................Diesel E/G with Rolling Code Type Immobilizer
1 3 9 ICU 2..................................................................Diesel E/G with Rolling Code Type Immobilizer
140 Injection Pump Valve Extension..........................Diesel E/G with Rolling Code Type Immobilizer
141 Injection Pump Valve Extension..........................Diesel E/G with Rolling Code Type Immobilizer
142 EGR Solenoid....................................................Diesel E/G
143 ICU led................................................................Diesel E/G with Rolling Code Type Immobilizer
144 Immobilizer Solenoid Valve..................................Diesel E/G with Crypto Type Immobilizer
147 Immobilizer Unit...................................................Diesel E/G with Crypto Type Immobilizer

BODY WIRING SYSTEM 9A-11
ENGINE ROOM
1 Engine Room Relay Box
1.1 Main Wiring Connector
1.2 Main Wiring Connector
1.3 Main Wiring Connector........................................Gasoline E/G
1.4 Joint
1.5 Compressor, Condenser Fan Relay.....................Diesel E/G
1.6 Condenser Fan Relay 2
1.7 Air Conditioner Relay
1.8 Resistor with Diode..............................................Gasoline E/G
1.9 Front Fog Lamp Relay
1.10 Condenser Fan Relay 1
1.11 Tail Lamp Relay
1.12 Horn Relay
2 Octane Selector...................................................Gasoline E/G with HFM
3 Preheating Unit....................................................Diesel E/G
4 Preheating Timer Unit..........................................Diesel E/G
5 ECS Main Wiring Connector................................ ECS
6 Brake Leveling Fluid Sensor
7 ABD Main Wiring Connector................................ABD 5.0
7-1 ABS Main Wiring Connector................................ABD 5.0
8 ABD main Wiring Connector................................ABD 5.0
9 Engine Temperature Sensor................................Diesel E/G
10 ABS 5.0 ECU.......................................................ABS 5.0
10-1ABD 5.0 Modulator...............................................ABD 5.0
11 Front Washer Motor.............................................Diesel E/G
12 Head Lamp Relay
13 Compressor .........................................................Air Conditioner
14 Wheel Speed Sensor...........................................ABS 5.0 or ABD 5.0

9A-12 BODY WIRING SYSTEM
15 LH Damper........................................................... ECS
16 Ground 1
17 Ground 2
18 Locking Hub Solenoid
19 Condenser Fan Relay.........................................Gasoline E/G
20 LH Position Lamp
21 LH Head Lamp
22 LH Head Lamp Leveling Device...........................Leveling Device
23 Thermo Switch 2..................................................Gasoline E/G with HFM
24 Thermo Switch 3..................................................Gasoline E/G with HFM & Air Conditioner
25 LH Front Fog Lamp
26 LH Horn...............................................................Black Out Driving Lamp (Domestic)
27 Condenser Fan Motor.........................................Diesel E/G
28 Black Out Driving Lamp.......................................Black Out Driving Lamp (Domestic)
29 LH Horn...............................................................Leveling Device
30 LH Condenser Fan Motor....................................Gasoline E/G with Air Conditioner
31 Thermo Switch 1..................................................Diesel E/G or Gasoline E/G with HFM
32 Resistor...............................................................Gasoline E/G with Air Conditioner
33 Thermo Switch 4..................................................Gasoline E/G with HFM & Air Conditioner
34 Ambient Censor...................................................Air Conditioner
35 RH Condenser Fan Motor....................................Gasoline E/G
36 RH Horn
37 RH Front Fog Lamp
38 RH Position Lamp
39 RH Head Lamlp
40 RH Head Lamp Leveling Device..........................Leveling Device
41 Wheeling Sensor................................................. ECS
42 Wheel Speed Sensor (FR)..................................ABS 5.0, 5.3 or ABD 5.0, 5.3
43 RH Damper.......................................................... ECS
44 Alternator Extension Connector...........................Gasoline E/G
45 Alternator .............................................................Gasoline E/G
46 Alternator Extension Joint box..............................Diesel E/G
47 Alternator Extension Connector...........................Diesel E/G
48 Ground 3
49 Fusible Link Box...................................................Gasoline E/G
49-1Fusible Link Box...................................................Diesel E/G
50 Receiver Dryer.....................................................Gasoline E/G with Air Conditioner
50-1Receiver Dryer.....................................................Diesel E/G with Air Conditioner
51 Hood Switch.........................................................Diesel E/G with Black Out Driving Lamp
52 Front Washer Motor.............................................Gasoline E/G
53 Main Wiring Connector