Mitsubishi LANCER EVOLUTION-VII 2001, Technical Information Manual

Page: 144 / 171

INTERIOR –
Supplemental Restraint System (SRS)
6-15
SRS-ECU
The SRS-ECU incorporates an analog G sensor
and safing G sensor for frontal collisions.
In frontal collisions, the driver’s and front passen-
ger’s air bags deploy only when both the analog
and safing G sensors detect simultaneously a colli-
sion-induced G of a level exceeding the threshold
as in the case with the conventional system.
Like the conventional system, the SRS-ECU is pro-
vided with the following capabilities:
D
Backup power supply in case of power failure
in collisions
D
Boosting function in case of battery voltage
drop
D
Self-diagnosis function to avoid system’s opera-
tion errors and improve its reliability
Caution
Never disassemble the SRS-ECU. And never
subject it to impact.
DIAGNOSIS FUNCTION
The SRS-ECU has the following functions to make
system checking using MUT-
II
easy.
D
Diagnosis code output
D
Service data output
DIAGNOSIS CODE OUTPUT
The SRS-ECU diagnoses the following items and
stores a diagnosis code in the non-volatile memory
(EEPROM*
1
) when a problem is detected.
Therefore, the memory is not deleted after a battery
terminal is disconnected. (The diagnosis code
memory can be deleted by the MUT-
II
.)
Code
No.
Major Contents of Diagnosis
14 Frontal collision analog G sensor failure
15 Frontal collision safing G sensor short-circuited
16 Frontal collision safing G sensor open-circuited
21*
3
Driver’s side front air bag squib short-circuited
22*
3
Driver’s side front air bag squib open-circuited
24*
3
Front passenger’s side front air bag squib short-circuited
25*
3
Front passenger’s side front air bag squib open-circuited
26*
3
Driver’s side front seat belt pretensioner short-circuited
27*
3
Driver’s side front seat belt pretensioner open-circuited
28*
3
Front passenger’s side front seat belt pretensioner short-circuited
29*
3
Front passenger’s side front seat belt pretensioner open-circuited
31 Capacitor voltage rises
32 Capacitor voltage drops
34*
2
Connector locking mechanism malfunction
35 Ignition of the air bag completed
41*
2
Power supply voltage (IG1 voltage) drops abnormally.
42*
2
Power supply voltage (IG1 voltage) drops abnormally.
43*
2
SRS warning lamp circuit open-circuited
44*
2
Defective SRS warning lamp circuit
45 Defective SRS-ECU
49 Air bag fully deployed
51 Driver’s side front air bag squib activating circuit short-circuited