1991 MITSUBISHI 3000GT key battery

35-24SERVICE BRAKES -Anti-lock Braking System Troubleshooting
E-5When diagnosis code “51 VALVE RELAY” is displayed
[Explanation]
When the ignition switch is turned ON, the ABS
ECU switches the valve relay OFF and ON for an
initial check, compares the voltage of the signal to
the valve relay and valve power monitor line voltage
to check whether the valve relay operation isnormal. In addition, normally it monitors whether or
not there is power in the valve power monitor line
since the valve relay is normally ON. Then, if the
supply of power to the valve power monitor line is
interrupted, this trouble code will be output.
EPfiiB EenIGNITIONSWITCH(IG1)
COMSINATIONm
I
H” g@J$s2
4:u
,,8I. -----I/IL’ /
IIII
I /IIII/I/-,----__--_,>yo “-a-‘+G ------------------ ?$”:
;’m[1?610 2pEl%zq~,___ ____________~_______~~~~
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$-:dL1:27 =Yi62.G 22 +%!
i.-I
1/2131a)5161718(QIIO(I ~~~2(13~~a~i5~~6/i7~~~IQ$O~Y~2~3~24~~6~~~28~~~1~2~3~4~5~Remove and check the valve relay.
IWhen the valve relay is checked, are
the following conditions found?
No. 85
-No. 86: Resistance
value 60 - 120 fiNo. 30-No. 87a: Continuity
No. 30 - No. 87: No continuity
When battery voltage is applied
between terminals No. 86 and No. 85.
No. 30
- No. 87: Continuity
No. 30 - No. 87a: No continuity
Yes
Install the valve relay and remove
the HU connector.
E+GG-pqReplace valve relay.
&I/ NnIIWith the ignition key “ON”, does the
Is there continuity between HU No. 8
and No. 7 terminals?
IYes
Connect the HU harness and remove
the ECU connector.Faulty harness in HU
1Does resistance between body con-
nector terminal No. 2 and terminal
No. 27 indicate 60
- 120 II
NoMalfunction of harness
between HU and ECU.
Yes
With the ignition key “ON”, does the
voltage between terminal No. 22 and
ground indicate battery voltage?
YesNo
II- Malfunction of harness
between HU and ABS
ECU.Repair harness.
vision

35-32SERVICE BRAKES -AniLlock Braking System Troubleshooting
NoWith the ignition key in the “ON” posi-
I--Check fuse No. 11. If it is
blown, correct the cause of
the blown fuse and then
replace the fuse.J
Yes
I
( ~;T&$Efg,?~ )harness connector terminal
No. 59 and ground indicate
battery voltage?
----F--
&Repair harness.
Circuit in combination meter
-is broken.
Is there continuity between combination
meter No. 58 and No. 59 terminals?
Are instrument panel wiring harness
and body wiring harness connected
Broken wire in ECU, valve relay or both
drive circuits. Check both circuits.
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SERVICE BRAKES -Anti-lock Braking System Troubleshooting35-33
1i, 1 CheckABSECU. ,
Remove the ECU connector and
check.Does the voltage between ECU harness
> Broken wire between ABSj Repair harness.
connector terminal No. 25 and ground
warning light and ECU
indicate battery voltage while the
ignition key is in the “ON” position?
Yes
> ABS ECU malfunction> Replace ABS ECU.
Remove valve relay and check.
I
1Nois valve relay normal? (Refer to
P.35-62.)) Valve relay malfunction+ Replace valve relay.IYes
Install the valve relay, remove the HU
connector and check.
Does voltage between the HU harness
uLEm-h[ Repair harness.
connector terminal No. 8 and ground
indicate battery voltage
while the
ignition key is in the “ON” position?
Yes
r7; t%$~?$!Je~~~g~undIIs there continuity between HU harness9 Repair harness.
connector terminal No. 9 and ground?
Is there continuity between HU harness
connector terminals No. 8 and No. 9?Yes+ HU malfunctionI+ Replace HU.
b Connector not connected
securely.- Replace connector.
1 TSB Revision

SERVICE BRAKES -Anti-lock Braking System Troubleshooting
35-35
IGNITIONSWITCH(IG2)
R&RRELAY
DIODE
KX35-AK-R35028PREVIOUS PAGE
With the ignition key in the
“ON” position, does voltage
between ECU connector
terminal No. 18 and ground
indicate the battery voltage?
Is there continuity between
body harness terminals No. 9
and No. 34, and ground?
Repair harness.
vNoIs there continuity between-body harness connector ter-diagnosis inspection
minals No. 23 and No. 24,terminal and ABS ECU
and diagnosis inspection ter-
minals No. 4 & No. 1 O?Yes
”Malfunction of ABS ECU
Replace ABS ECU.
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SERVICE BRAKES -Anti-lock Braking System Troubleshooting35-37
DABS warning light blinks once after the ignition key is turned to the “ON” position. It
Lilluminates in the “START” position and blinks once again when turned to the “ON” position.
[Explanation]
1 sec. while itharness between the ECU and the warning light, the
light illuminates only when the valve relay is off in
performs a valve relay test. If there is a break in the
the valve relay test, etc.
IGNITIONSWITCH(IG1)I
J/B
F
2
r+im
md
/
L/
COMBINATION
METER
ABS-ECU-____
KK35-KK-It3503In the ignition key “ON”
position, does voltage
between terminal No. 25 and
ground indicate battery
voltage?ABS warninglight and
Yes
Repair harness.
vMalfunction of ABS ECU
+ Replace ABS ECU.
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35-40SERVICE BRAKES -Anti-lock Braking System Troubleshooting
E-3When diagnosis code “21 G SNSR.” is displayed
[Explanation]
The ABS-ECU outputs this trouble code in the
following cases.
l G sensor OFF trouble (It is judged that the G
sensor continues to be OFF for more than
approximately 13 seconds except when thevehicle is stopped or when there is stop light
switch input.)
lWhen there is a broken wire or short circuit in
the harness for the G sensor system.
FUSIBLE LINK@
4
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2
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It
I,1II1 Ii II II II Ii II II I/ II ;/ II II II II !: II//IIII/.--A
X35-LK-R9505
I
IiNo IfIs G sensor normal? (Refer
to
P.35-92.)Replace G sensor.
I
Yes
Remove the ABS-ECU
connector and check at
the harness connector.
With the ignition key “ON”,
does the voltage between
terminal No. 6 and groundindicate battery voltage?
Repair harness.
”
ABS-ECU malfunctionIJP Replace ABS-ECU.
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SERVICE. BRAKES -Anti-lock Braking System Troubleshooting35-43
E-6When diagnosis code “51 VALVE RELAY” is displayed
I
L[Explanation]
When the ignition switch is turned ON, the ABS
normal. In addition, normally it monitors whether or
ECU switches the valve relay OFF and ON for annot there is power in the valve power monitor line
initial check, compares the voltage of the signal tosince the valve relay is normally ON. If the supply of
the valve relay and valve power monitor line voltagepower to the valve power monitor line is inter-
to check whether the valve relay operation is
rupted, this trouble code will be output.
b
L
IGNlTIONSWITCH(IG1)
-I--
iz
=pi7TEaq
dI
6
7
Ed
COMBINATION
METER
--;Gm1 I 11
I /I
--- --
710 4Ii+
mI%
~d10 2
--- -- -?
ii3Dz62 27
iE b
1112j31a15(6/71618/10(11112113/14/15j16/17(18118~20~21~2~3~4~5~~~2@~~~0~31~2~3~~~35
KX35-AK-K3503
r-TSB I
( ;;reove;d ch; the>
4.IWhen the valve relay is checked,
are the following conditions
found?
No. 85
- No. 86: Resrstance
value 60 - 120 IINo. 30-No. 87a: Continuity
No. 30 - No. 87: No continuity
When batterv voltaoe IS aooliedbetween terminalsho. 86 and
No. 85.
No. 30
- No. 87: Contrnurty
No. 30 - No. 87a: No continurtyNo
I1-----+Valve relay malfunction
+l
IReplace valve relay.I
Yes
&I/ No1IWith the ignition key “ON”,
does the voltage between the
connector terminal No. 52 and
ground indicate battery voltage?
Yes
Connect the HU harness and
\ remove the ECU connector.
+II NnrIground Indicate battery voltage.
Replace ABS
ECIJ.
vision

42-56BODY - Central Door Locking System
CHECKING INDIVIDUAL PART AND CIRCUIT (IGNITION KEY REMINDER SYSTEM)
1. ETACS POWER-SUPPLY AND GROUND CIRCUITS
L-
Batterv
$1,\ .
\I \/ \I
‘/1,\/2-“1
m+,2T.,l\ ,.c.i -
151
Junction block (Multi-purpose fuse)
Jumper connector
ETACS unit(ECU)
“I : Vehicles without theft-alarm system
“2: Vehicles with theft-alarm systemz1116FO314Description of operation
The battery supplies a stabilized 5V power supply to the electronic control unit, via the constant-voltage circuit
and terminal (51) directly connected to the battery. If there is an abnormal condition of the power-supply
circuit, other ETACS functions also will not operate.
Electronic control unit terminal voltage (Connection status of electronic control unit connector)
ECU terminal No. Signal
StatusTerminalvoltage
I
51Electronic control unit power supply
At all timesSystem
voltage
IChecking the ground circuit (Disconnect the connector and check the wiring harness side.)
IIII1Terminal No.Connected to/measured part
MeasurementTesterconnectionCheck conditionsStandard57”’
Electronic control unit ground
Resistance57*‘-groundAt all timesContinuity
59”)59*2-ground
NOTE
“I : Vehicles without theft-alarm system.“2: Vehicles with theft-alarm system
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