ECU MITSUBISHI 3000GT 1991 Service Manual

EXTERIOR - Windshield Wiper and Washer
3. INTERMITTENT VARIABLE VOLUME SWITCH INPUT CIRCUIT51-29
ETACSunit (ECU)Xi
i-7 II Column switch
JIB
*l : Vehicles without theft-alarm system
“2: Vehicles with theft-alarm systemA-16FO321
eiOperation Description
This circuit functions to input (to the intermittent time interval detection circuit of the electronic control unit)
the set value of the intermittent variable volume switch.
Electronic Control Unit Terminal Voltage (Connection Status of Electronic Control Unit Connector)
ECU terminal No.
SignalStatusTerminal
voltage
13”’
15*2Intermittent variable
volume switch signalIntermittent variable volume switch“FAST” -+ “SLOW”0 + 2.5V
Checking the Intermittent Variable Volume Switch Circuit (Disconnect the Connector of the Electronic
Control Unit and Check at the Wiring Harness Side.)
ECUterminal No.
13”’
15*2
Connected to/measured
component
Intermittent variable
volume switchMeasurement TesterCheck conditionStandardconnection
Resistance
13*‘-ground“FAST” + “SLOW”O+ IkS1(Should change in
1 S*‘-groundaccordance with
changes of the inter-
mittent variable
volume.)Checking Individual Part
Intermittent variable volume switch: Refer to
P.51-33./
idNOTE
“1: Vehicles without theft-alarm system
“2: Vehicles with theft-alarm system
TSB Revision

51-30
EXTERIOR - Windshield Wiper and Washer
4. WIPER RELAY ACTIVATION CIRCUIT
Columnswitch
ETACS untt(ECU) t,
lgnttton switch (ACC)I
Junction block(Multi-purpose fuse)0.85L
*11 $0J\
i?+”
coii
aIt
0.85L-W dA
*’II16FO322
Wiper
motor
Ei
123 4
Operation Description
With the wiper switch at the “INT” position, switch ON the transistor (by the intermittent activation signal
from the electronic control unit) in order to activate the wiper relay.
Electronic Control Unit Terminal Voltage (Connection Status of Electronic Control Unit Connector)
ECUterminal No.SignalStatusTerminal
voltage
4”’
6*2Wiper relay signal)N$Fy switch
I,Ignition switch “OFF”
Ignition switch “ACC”ov
System
voltage
NOTE“I : Vehicles without theft-alarm system
“2: Vehicles with theft-alarm system
Checking Individual Part
Wiper relay: Refer to
P.51-34.
Lj 1
I
I
I
I
‘d ’1
I
\ ~
1 TSB Revision

EXTERIOR - Windshield WiDer and Washer51-315. WASHER SWITCH INPUT CIRCUIT
lgnitlon swatch (ACC)
Columnswitch
ETACS unit(ECU)*,
-7-l
Junction block15~ @ (Multi-purpose fuse)
ON-time detec-\I\I1a
“I : Vehicles without theft-alarm system
“2: Vehicles with theft-alarm system16FO323
Operation Description
While the washer switch is ON, HIGH-level signals are sent to the washer switch ON-time detection circuit
simultaneous with the activation of the washer motor, thus causing the transistor to be switched ON and the
wipers to be activated for a certain fixed time.
Electronic Control Unit Terminal Voltage (Connection Status of Electronic Control Unit Connector)
ECUterminal No.58”’
60*2Signal
Washer switch signal
Status
Ignition switch
“ACC”Washer switch “OFF”Washer switch “ON“
Terminal
voltageov
System
voltage
NOTE*I : Vehicles without theft-alarm system
“2: Vehicles with theft-alarm systemChecking Individual Part
Washer switch: Refer to
P.51-33
1 TSB Revision

52A-12INTERIOR - Trims
19POO70
4Trim
19POO80
hornm
in.)
19POO8,
Pin
Trim
19POO8219POO80TRIMS
IM52UCW
TRIM CLIP REMOVAL/INSTALLATION
PROCE-DURES
The type of clip shown in the illustration, which is used for the
Eli ~
installation of instrument panel, should be removed and
installed by the following procedures described below.
REMOVAL
(1) Use a cross-tip (+) screwdriver to push inward the pin (at
the center of the trim clip) to a depth of about 2 mm
(.08
in.).(2) Pull the trim clip outward to remove it.
Caution
Do not push the pin inward more than necessary
because it may damage the grommet, or the pin may
fall in, if pushed too far.
INSTALLATION
(1) With the pin pulled out, insert the trim clip into the hole in
the trim.
(2) Push the pin inward until the pin’s head is flush with the
grommet.
(3) Check whether the trim is secure.
TSB Revision

INTERIOR - Front Seat52A-23
(2) Disconnect the connector of each limit switch and check for
continuity between terminals.
lFr= ) I / * / 3 j
Highest00
Medium0
Lowest0
0
NOTEO-O indicates that there is continurty between the terminals,
(3) Make sure that portion A of the harness does not interfere
with the selector gear.
SERVICE POINT OF REASSEMBLY9. INSTALLATION OF INNER SEAT BELT
(1) Route the seat belt switch connector harness on the
adjuster bracket.
(2) Use clips to secure the harness to the adjuster bracket.
(3) Fit the locking claw of the inner seat belt positively in
the locking hole provided in the seat bracket.
iJ
TSB Revision

INTERIOR - Seat Belt52A-27
CHECKING INDIVIDUAL PART AND CIRCUIT
IGNITION SWITCH INPUT CIRCUITBattery
Fusible link
2oB-y~~/l,l(l,l,,~~ !jw u03w
30AJunction block
*I : Vehicles without theft-alarm system“2: Vehicles wtth theft-alarm system16FO35.3
It/Description of operationA condition for operation of this system is the sending of HIGH-level signals to the electronic control unit
when the ignition switch is switched to the “ON” position.
Electronic control unit terminal voltage (Disconnect the connector of the electronic control unit andcheck the wiring harness side.)
IECU terminal No. SignalCondition-1 ~StandardI
52Ignition switch “ON”Ignition switchOFF
ONov
System
voltageChecking the ground circuit (Disconnect the connector and check the wiring harness side.)
Terminal No.Connected to/measured part
57,’Electronic control unit ground
59*2
NOTE
*I : Vehicles without theft-alarm system
“2: Vehicles with theft-alarm systemMeasurementTester
connectronCheck conditionsStandard
Resistance
57*‘-groundAt all timesContinuity
59*.‘-groundChecking the individual part
Ignition switch: Refer to GROUP 54
- Ignition Switch.
1 TSB Revision

52A-28INTERIOR - Seat Belt2. SEAT BELT WARNING LIGHT AND BUZZER ACTIVATION CIRCUIT
Fusible link @
Junctron block(Multr-purpose fuse)
ETACS unit (ECU)Description of operation
Place the ignition switch in the ON position, and the transistor will be turned on, blinking the warning light and
sounding the buzzer four times. However, the warning buzzer will not sound unless the key-reminder switch
and seat belt switch are in the ON position.
Electronic control unit terminal voltage (Disconnect the connector of the electronic control unit andcheck the wiring harness side.)
IIIIIECU terminal No. Signal
ConditionTerminal
voltageI\!
Warning light signalAt all timesSystem
6*1voltage
Warning buzzer signal
Key-reminder switch or seat belt switch “OFF”ov8*2
Key-reminder switch and seat belt switch “ON”System
voltage
NOTE“1. Vehicles without theft-alarm system
“2: Vehicles with theft-alarm systemChecking the individual part
Key-reminder switch: Refer to GROUP 54
- Ignition Switch.dSeat belt switch: Refer to
P.5?A-30.
1 TSB Revision

52A-30
INTERIOR - Seat Belt
16M456
NOTEO-O indicates that there is continuity between the terminals.
BUZZERCheck that buzzer sounds when battery voltage is applied to
the buzzer terminal.
Paw1 to
prevent
\1retractor
Bead
INSPECTION
BUCKLE SWITCH(1) Disconnect the buckle switch connector.
(2) Check the continuity between the terminals.
Terminal
1234
Buckle unlock00
Buckle lock00
i
“..i,Tlmdsmrawlro -6I J3JJAdjuster’bracketJ’JJ’ prevent
rotation19FO128
Paw1 to prevent
rotation19FO120
SERVICE POINTS OF INSTALLATION6. INSTALLATION OF OUTER SEAT BELT
(1) Positively insert the
paw1 to prevent the retractor from
rotating in the hole provided on the body.
(2) Install the anchor plate along the bead of the body.
4. INSTALLATION OF INNER SEAT BELT
(1) Route the seat belt switch connector harness on the
adjuster bracket.
(2) Use clips to secure the harness to the adjuster bracket.
(3) Fit the locking claw of the inner seat belt positively in
the locking hole provided in the seat bracket.
2. INSTALLATION OF OUTER SEAT BELT
(1) Positively insert the
paw1 to prevent the retractor from
rotating in the hole provided on the body.
(2) After connecting the seat belt harness with the body
harness, insert the clip on the connector into the hole
on the body panel.
LA
I
I
I
I
I\
Jl
I
I
I
I
I
\ ~
L&l
TSB Revision

52B-10SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General InformationI
FIT VERIFICATION MECHANISMSecondary
lock leverThe mechanism electrically verifies that the connectors of the
SRS diagnosis unit have been fitted. The operating principle is
:described below.
d
(
(1) Securely connect the SRS diagnosis un.it and harness side
connectors and press the secondary lock lever down to lock
the connectors.
sisiarness side connector
13R0687Short bar
nlnal13R068E
Press-fitted tab terminals
13R0689Short
terminal (open)
plate
IShort terminal
I13R06911(2) At the time, the short bar provided on the rear of the
secondary lock lever shorts the associated two pole
terminals of the SRS diagnosis unit. The SRS diagnosis unit
supplies monitoring current to the circuit to electrically
verify that the connectors have been locked.
CONNECTOR SHORTING MECHANISMThe mechanism is designed for prevention of accidental
explosion of the inflator when the clock spring connector (for
the squib circuit) is removed from the SRS diagnosis unit. The
operating principle is described below.
When Connectors Are Fitted
When the SRS diagnosis unit and clock spring connectors are
coupled, the circuit between the short terminals and clock
spring connector terminals are kept in the OFF state by the
partition plate provided in the connector of the SRS diagnosis
unit.
When Connectors &e DisconnectedWhen the clock spring connectors are disconnected from the
SRS diagnosis unit, the partition plate between the short
terminals and clock spring connector terminals is removed. As
a result, a short circuit is formed between the two poles of the
clock spring connector terminals to prevent generation of a
potential difference (current) between the squib terminals.
TSB Revision1

LSUPPLEMENTAL RESTRAINT SYSTEM (SRS)
- Troub!eshooting 529-29
/ CONTINUED FROM PREVIOUS PAGE/*
(1)Connect the red 2-pin connector @ of the SRS CheckHarness to the SDU in place of the now-disconnected clock spring-SDU connector.
NOTEA 3-ohm resistor that corresponds to the resistance
of the air bag module (squib) and the wiring resis-
tance is connected between the terminals of the
connector
@ of the SRS Check Harness.
(2)Reconnect blue.and yellow connectors, for the wiring
leading to the front impact sensors, to the SDU anddouble lock them. (Refer to
P.52B-9.)
NOTEIf double locking cannot be made, the connector isincorrectly or incompletely inserted; re-check to
insert the connector correctly and securely.
”
CONTINUED ON NEXT PAGEIMB991 349
SRS Check Harness
SRS CheckHarness
\ ii%\19FOO93NOTE
- IMPORTANT
(I) After repairing the SRS, reconnect the battery cable, erase the diagnosis code memory from theMulti-use Tester and check the SRS warning light operation to verify the system functions
properly. (Refer to TEST 1.)
(2) SDU
= SRS Diagnosis Unit
i
TSB Revision