Downloaded from www.Manualslib.com manuals search engine − INTRODUCTIONFOR ALL OF VEHICLES
IN−13
13 Author: Date:
1996 TOYOTA T100 (RM449U)
(f) CENTER AIRBAG SENSOR ASSEMBLY
(1) Never reuse the center airbag sensor assembly in-
volved in a collision when the SRS has deployed.
(2) The connectors to the center airbag sensor assem-
bly should be connected or disconnected with the
sensor mounted on the floor. If the connectors are
connected or disconnected while the center airbag
sensor assembly is not mounted to the floor, it could
cause undesired ignition of the supplemental re-
straint system.
(3) Work must be started after 90 seconds from the
time the ignition switch is turned to the ”LOCK” posi-
tion and the negative (−) terminal cable is discon-
nected from the battery, even if only loosening the
set bolts of the center airbag sensor assembly.
(g) WIRE HARNESS AND CONNECTOR
The SRS wire harness is integrated with the cowl wire har-
ness assembly and floor wire harness assembly. The
wires for the SRS wire harness are encased in a yellow
corrugated tube. All the connectors for the system are
also a standard yellow color. If the SRS wire harness be-
comes disconnected or the connector becomes broken
due to an accident, etc., repair or replace it.
2. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
CAUTION:
If large amount of unburned gasoline flows into the converter, it may overheat and create a fire haz-
ard. To prevent this, observe the following precautions and explain them to your customer.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid running the engine at idle speed for more than 20 minutes.
(c) Avoid spark jump test.
(1) Perform spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
(2) While testing, never race the engine.
(d) Avoid prolonged engine compression measurement.
Engine compression tests must be done as rapidly as possible.
(e) Do not run engine when fuel tank is nearly empty.
This may cause the engine to misfire and create an extra load on the converter.
(f) Avoid coasting with ignition turned off and prolonged braking.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
Downloaded from www.Manualslib.com manuals search engine R07710R07711H00318
w/ Tachometer
w/o Tachometer
DI0XJ−02
S08098
E1 Tc
AT0716
Normal Code
ON
OFF0.25
0.25
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI−365
1996 TOYOTA T100 (RM449U)
PRE−CHECK
1. SRS WARNING LIGHT CHECK
(a) Turn the ignition switch to ACC or ON and check that the
SRS warning light lights up.
(b) Check that the SRS warning light goes out after approx.
6 seconds.
HINT:
When the ignition switch is at ACC or ON and the SRS
warning light remains on or flashes, the airbag sensor as-
sembly has detected a malfunction code.
If, after approx. 6 seconds have elapsed, the SRS warn-
ing light sometimes lights up or the SRS warning light
lights up even when the ignition switch is OFF, a short in
the SRS warning light circuit can be considered likely.
Proceed to ”SRS warning light system malfunction” on
page DI−398, DI−400.
2. DTC CHECK (Using diagnosis check wire)
(a) Output the DTC.
(1) Turn the ignition switch to ACC or ON position and
wait approx. 20 seconds.
(2) Using SST, connect terminals Tc and E1 of the
DLC1.
SST SST 09843−18020
NOTICE:
Never make a mistake with the terminal connection posi-
tion as this will cause a malfunction.
(b) Read the DTC.
Read the 2−digit DTC as indicated by the number of times
the SRS warning light blinks. As an example, the blinking
patterns, normal, 11 and 31 are as shown on the illustra-
tion.
Normal code indication:
The light will blink 2 times per second.
Malfunction code indication:
The first blinking output indicates the first digit
of a 2−digit DTC. After a 1.5 second pause,
the second blinking output will indicate the
second digit.
Downloaded from www.Manualslib.com manuals search engine R07090
W05586 W05587
H00319
TerminalTime of Body ground
Tc
ABOFF
Body
Ground
OFF
Body
Ground
Several
seconds50 msec.
50 msec. OFF ON
1 second
(± 0.5 sec.)1 second
(± 0.5 sec.)”1””3” ”5”
”2” ”4”
w/ Tachometer w/o TachometerAB
Tc
S07739
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI−367
1996 TOYOTA T100 (RM449U)
(d) Several seconds after doing the clearing procedure, the
SRS warning light will blink in a 50 msec. cycle to indicate
the codes have been cleared.
5. DTC CLEARANCE (Using TOYOTA hand−held tester)
(a) Hook up the TOYOTA hand−held tester to the DLC1.
(b) Clear the DTCs by following the prompts on the tester
screen.
HINT:
Please refer to the TOYOTA hand−held tester operator’s manu-
al for further details.
6. RELEASE METHOD OF AIRBAG ACTIVATION PRE-
VENTION MECHANISM
An airbag activation prevention mechanism is built into the con-
nector for the squib circuit of the SRS.
When release of the airbag activation prevention mechanism is
directed in the troubleshooting procedure, as shown in the il-
lustration of the connectors ”1” and ”2” below, insert paper
which is the same thickness as the male terminal, between the
terminal and the short spring.
Downloaded from www.Manualslib.com manuals search engine DI0XK−02
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI−369
1996 TOYOTA T100 (RM449U)
DIAGNOSTIC TROUBLE CODE CHART
If a malfunction code is displayed during the DTC check, check the circuit listed for that code in the table
below (Proceed to the page given for that circuit.).
DTC No.
(See Page)Detection ItemTrouble AreaSRS
Warning Light
Normal
(DI−396)System normal−OFF
Source voltage dropBattery
Center airbag sensor assemblyON
11
(DI−373)
Short in squib circuit or front airbag
sensor circuit (to ground)Steering wheel pad (D squib)
Front airbag sensor
Spiral cable
Center airbag sensor assembly
Wire harness
ON
12
(DI−379)
Short in squib circuit or front airbag
sensor circuit (to B+)Steering wheel pad (D squib)
Front airbag sensor
Spiral cable
Center airbag sensor assembly
Wire harness
ON
14
(DI−385)
Open in D squib circuitSteering wheel pad (D squib)
Spiral cable
Center airbag sensor assembly
Wire harness
ON
15
(DI−390)Open in front airbag sensor circuitFront airbag sensor
Center airbag sensor assembly
Wire harness
ON
31
(DI−394)
Center airbag sensor assembly
malfunctionCenter airbag sensor assembly
ON
HINT:
When the SRS warning light remains lit up and the DTC is the normal code, this means a source voltage
drop. This malfunction is not stored in memory by the center airbag sensor assembly and if the power
source voltage returns to normal, approx. 10 seconds the SRS warning light will automatically go out.
When 2 or more codes are indicated, the lowest numbered code will apper first.
If a code not listed on the chart is displayed, the center airbag sensor assembly is faulty.
Downloaded from www.Manualslib.com manuals search engine R15204
J/B No.1
Center Airbag
Sensor Assembly Ignition
SwitchShort
Connector Integration
Relay
R/B No.2
BatteryGR−RGR−R
B−YB−YACC
IG2
R−L
B−R L−R
CIG
IGN
ALT
AM1
AM2
WW
W
W
W−R
1A
1A 1CIA3
IA3
W−R34
34
16
15
17 3 4
7 2
83 14
8 2
2
2 2 2 26
4
2 5
13 DI−396
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1996 TOYOTA T100 (RM449U)
DTC Normal Source Voltage Drop
CIRCUIT DESCRIPTION
The SRS is equipped with a voltage−increase circuit (DC−DC converter) in the center airbag sensor assem-
bly in case the source voltage drops.
When the battery voltage drops, the voltage−increase circuit (DC−DC converter) functions to increase the
voltage of the SRS to normal voltage.
The diagnosis system malfunction display for this circuit is different to other circuits−when the SRS warning
light remains lit up and the DTC is a normal code, source voltage drop is indicated.
Malfunction in this circuit is not recorded in the center airbag sensor assembly, and the source voltage re-
turns to normal, after approx. 10 seconds the SRS warning light automatically goes off.
DTC No.Diagnosis
(Normal)Source voltage drop
WIRING DIAGRAM
DI989−01
Downloaded from www.Manualslib.com manuals search engine H18114
ONAirbag Sensor Assembly
IG
2Acc
(+) (−)
AB0119AB0234H00351
ON
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI−397
1996 TOYOTA T100 (RM449U)
INSPECTION PROCEDURE
1 Preparation.
PREPARATION:
(a) Turn ignition switch to LOCK.
(b) Disconnect center airbag sensor assembly connector.
(c) Turn ignition switch ON. But do not start engine.
(d) Measure voltage between terminal IG
2 or ACC on con-
nector wire harness side of center airbag sensor assem-
bly and body ground, and operate electric system (defog-
ger, wiper, headlight, heater blower, etc.).
Voltage: 6 V − 11.5 V at IG
2 and ACC
(e) Turn electric system switch OFF.
(f) Turn ignition switch to LOCK.
(g) Remove voltmeter and connect center airbag sensor as-
sembly connector.
2 Does SRS warning light turn off?
PREPARATION:
(a) Turn ignition switch to LOCK.
(b) Connect steering wheel pad connector.
(c) Connect center airbag sensor assembly connector.
(d) Turn ignition switch ON.
CHECK:
Operate electric system (defogger, wiper, headlight, heater
blower, etc.), and check that SRS warning light goes off.
NO Check for DTCs. If a DTC is output, perform trou-
bleshooting for DTC. If a normal code is output,
replace center airbag sensor assembly.
YES
From results of above inspection, malfunctioning part can now be considered normal. To make
sure of this, use simulation method to check.
Downloaded from www.Manualslib.com manuals search engine R15207
Center Airbag
Sensor Assembly
Relay Block
No.2
ECU−B SRS Warning Light
Battery
Short
ConnectorY−B Y−B
P−B P−B
P−B P−B Y−B
P−B
DLC1
TC
LA Tc
ABIE1
IE2
IA3 W
WYR
ALT
7
21211 2
2 1
2
58 6
8
5 11
22 11 DI−398
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1996 TOYOTA T100 (RM449U)
SRS Warning Light Circuit Malfunction (Always lit up, when
ignition switch is in LOCK position.)
CIRCUIT DESCRIPTION
The SRS warning light is located on the combination meter.
When the SRS is normal, the SRS warning light lights up for approx. 6 seconds after the ignition switch is
turned from LOCK position to ACC or ON position, and then turns off automatically.
If there is a malfunction in the SRS, the SRS warning light lights up to inform the driver of the abnormality.
When terminals Tc and E1 of the DLC1 are connected, the DTC is displayed by the blinking of the SRS warn-
ing light.
WIRING DIAGRAM
DI98A−01
Downloaded from www.Manualslib.com manuals search engine H18115
LOCK
Center Airbag
Sensor Assembly
− DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI−399
1996 TOYOTA T100 (RM449U)
INSPECTION PROCEDURE
1 Does SRS warning light turn off?
PREPARATION:
(a) Turn ignition switch to LOCK.
(b) Disconnect negative (−) terminal cable from the battery,
and wait at least 90 seconds.
(c) Disconnect center airbag sensor assembly connector.
(d) Connect negative (−) terminal cable to battery.
CHECK:
Check operation of SRS warning light.
NO Check SRS warning light circuit or terminal AB
circuit of DLC1.
YES
Replace center airbag sensor assembly.