Mitsubishi Galant 9G. Manual — part 1429
SRS AIR BAG DIAGNOSIS
TSB Revision
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
52B-126
STEP 7. Check the side-airbag module (RH) circuit.
Measure the resistance at the SRS-ECU connector C-120.
(1) Disconnect SRS-ECU connector C-120.
DANGER
To prevent the air bag from deploying unintentionally,
disconnect the side-airbag module (RH) connector
D-32 to short the squib circuit.
(2) Disconnect side-airbag module connector D-32.
CAUTION
Insert an insulator such as a cable tie to a depth of 4mm
(0.16 inch) or more, otherwise the short spring will not be
released.
(3) Insert a cable tie [3 mm (0.12 inch) wide, 0.5 mm (0.02 inch)
thick] between terminals 57, 58 and the short spring to
release the short spring.
(4) Measure at the wiring harness side.
CAUTION
Do not insert a test probe into the terminal from its front
side directly, as the connector contact pressure may be
weakened.
(5) Check for continuity between C-120 harness side connector
terminals 57 and 58.
It should be open circuit.
Q: Does continuity exist?
YES : Go to Step 8.
NO : Erase the diagnostic trouble code memory, and check
the diagnostic trouble code. If DTC B1420 sets,
replace the SRS-ECU (Refer to
). Then go
to Step 7.
AC305362
CONNECTOR: C-120
C-120 (Y)
AG
SRS-ECU
63
55
51
69
61
66
58
65
64
56 57
68
60
67
59
70
62
53
52 B
A
54
C-120
Harness side
connector
(rear view)
AC307779
D-32 (R)
AD
2
1
HARNESS SIDE
CONNECTOR
(REAR VIEW)
CONNECTOR : D-32
AC301607AC
C-120 HARNESS SIDE
CONNECTOR (FRONT VIEW)
TERMINAL
CABLE
TIE
SECT-
ION
A - A
4 mm (0.16 inch) OR MORE
SHORT SPRING
A
A
AC301573
63
55
51
69
61
66
58
65
64
56 57
68
60
67
59
70
62
53
52 B
A
54
C-120 HARNESS SIDE
CONNECTOR
(REAR VIEW)
AD
SRS AIR BAG DIAGNOSIS
TSB Revision
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
52B-127
STEP 8. Check the harness wires for short circuit between
SRS-ECU connector C-120 (terminal No.57 and 58) and
side-airbag module (RH) connector D-32 (terminal No.1
and 2).
Q: Are the harness wires between SRS-ECU connector
C-120 (terminal No.57 and 58) and side-airbag module
(RH) connector D-32 (terminal No.1 and 2) in good
condition?
YES : Go to Step 9.
NO : Repair the harness wires between SRS-ECU
connector C-120 and side-airbag module (RH)
connector D-32. Then go to Step 9.
STEP 9. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC B1420 set?
YES : Return to Step 1.
NO : The procedure is complete.
AC305362
CONNECTOR: C-120
C-120 (Y)
AG
SRS-ECU
63
55
51
69
61
66
58
65
64
56 57
68
60
67
59
70
62
53
52 B
A
54
C-120
Harness side
connector
(rear view)
AC307779
D-32 (R)
AD
2
1
HARNESS SIDE
CONNECTOR
(REAR VIEW)
CONNECTOR : D-32
AC305412
AB
MB991910
DATA LINK
CONNECTOR
MB991824
MB991827
SRS AIR BAG DIAGNOSIS
TSB Revision
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
52B-128
DTC B1421: Side-Airbag Module (RH) (Squib) System Fault 2 (Open in the Squib Circuit)
CAUTION
If DTC B1421 is set in the combination meter,
always diagnose the CAN bus lines.
.
CIRCUIT OPERATION
• The SRS-ECU judges how severe a collision is
by detecting signals from the left and right side
impact sensors. If the impact is over a predeter-
mined level, the SRS-ECU sends an ignition sig-
nal. At this time, if the side-airbag safing
G-sensor is on, the SRS side-airbag will inflate.
• The ignition signal is input to the side-airbag
module to inflate the side-airbag.
.
DTC SET CONDITIONS
This DTC is set if there is abnormal resistance
between the input terminals of the side-airbag mod-
ule (RH) (squib).
.
TROUBLESHOOTING HINTS
• Open circuit in the side-airbag module (RH)
(squib) circuit
• Improper connector contact
• Malfunction of the SRS-ECU
.
SIDE AIR BAG
MODULE
(SQUIB) (RH)
AIR BAG DRIVE CIRCUIT
SRS-ECU
CONNECTOR
LOCK SWITCH
CONNECTOR
LOCK SWITCH
Side-Airbag Module (RH) (Squib) Circuit
NOTE
: CONNECTOR
CONNECTED
: ON
CONNECTOR
DISCONNECTED
: OFF
AC305362
CONNECTOR: C-120
C-120 (Y)
AC
SRS-ECU
AC307779
D-32 (R)
AC
CONNECTOR : D-32
SRS AIR BAG DIAGNOSIS
TSB Revision
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
52B-129
DIAGNOSIS
Required Special Tools:
• MB991958: Scan Tool (MUT-III Sub Assembly)
• MB991824: Vehicle Communication Interface (V.C.I.)
• MB991827: MUT-III USB Cable
• MB991910: MUT-III Main Harness A (Vehicles with CAN
communication system)
• MB991865: Dummy resistor
• MB991866: Resister harness
STEP 1. Using scan tool MB991958, diagnose the CAN bus
line.
CAUTION
To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958. Refer to "How to connect the
scan tool
."
(2) Turn the ignition switch to "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES : Go to Step 2
NO : Repair the CAN bus lines (Refer to GROUP 54C,
AC305412
AB
MB991910
DATA LINK
CONNECTOR
MB991824
MB991827
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст