Page 1060 of 2389
Check that there is voltage between ECU terminal + B or + B1 and body
ground. (IG SW ON) No voltage between ECU terminal 1D1. or PSW and E1.
(IG SW ON)
Check wiring between ECU terminal El and body
ground.
Check wiring between ECU and
throttle position sensor. Check throttle position sensor.
(See page FI±106)
Replace or repair throttle
position sensor. Refer to No. 1.
(See page FI±34) Throttle valve fully closedThrottle valve open
Repair or replace.
Repair or replace.
Try another ECU.STD voltage
No voltageIG SW ONCondition
TerminalsTrouble
BAD
BAD
BAD
BAD No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±36
Page 1061 of 2389
Check that there is voltage between ECU terminal +B or +B1 and body
ground. (IG SW 4111)
Check wiring between ECU terminal El and body
ground. No voltage between ECU terminals IDL and E2.
OG SW ON) (Throttle valve open)
Check wiring between ECU and
throttle position sensor. Check throttle position sensor.
(See page FI±110)
Repair or replace throttle
position sensor.Refer to No. 1.
(See page FI±34) Throttle valve fully closed
Throttle valve fully open
Try another ECU. Throttle valve open
Repair or replace.Repair or replace.
wIDL ± E2
STD voltage
No voltage
IG SW ON
Condition Terminals Trouble
BAD
BAD
BAD
BAD
No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±37
Page 1062 of 2389
Check that there is voltage between ECU terminal +B or +131 and
body ground. (IG SW ON)
Check that there is voltage between ECU terminal VC and E2
(IG SW ON)No specified voltage at ECU terminals VTA and E2.
(IG SW ON) No voltage between ECU terminals VC and E2.
(IG SW ON)
Check wiring between ECU and throttle
position sensor.
Check wiring between ECU and
throttle position sensor.Check throttle position sensor
(See page FI±110) Check throttle position sensor.
(See page FI±110)
Repair or replace
wiring.
Refer to NO±1.
(See page FI±34)
Refer to VC±E2
trouble section
Repair or replace.
Repair or replace. Repair or replace.
Try another ECU.
Try another ECU.
wNTA ± E2 wVC±E2
BAD
BAD
BAD
BAD
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±38
Page 1065 of 2389
Check that there is voltage between ECU terminal +B or +B1 and
body ground. (IG SW 4N)
Check wiring between ECU terminal E1 and body
ground.No voltage between ECU terminals THA and E2.
(IG SW ON)Intake air temperature 20°C
(68°F)
Check wiring between ECU and air
temp. sensor. Check air temp. sensor.
(See page FI±104)Refer to No. 1.
(See page FI±34)
Replace air
flow meter.Repair or replace.
Repair or replace.
Try another ECU.STD voltage
No voltageIG SW ONCondition Terminals
Trouble
BAD
BAD BAD
No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±41
Page 1066 of 2389
Check that there is voltage between ECU terminal +B or +131 and
body ground. (IG SW ON)
No voltage between ECU terminals THW
and E2.
(IG SW ON)
Check wiring between ECU terminal El and body
ground.
Check wiring between ECU and water
temp. sensor. Check water temp. sensor.
(See page FI± 1 Z5)Coolant temperature 8O° (176°F)
Refer to NO. 1.
(See page FI±34)
Replace water
temp. sensor.Repair or replace.
Repair or replace.
Try another ECU.STD voltage
No voltage
IG SW ON Terminals
Condition Trouble
BAD
BAD
BAD
No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±42
Page 1072 of 2389
Check that there is specified voltage between ECU terminal VF
and body ground.
Check for suction of air into exhaust
system.Check wiring between ECU terminal E1 and body ground.
Check wiring between oxygen sensors and
ECU connectors.There is no voltage between ECU terminals VF and E1.
Check for air leak from air intake system.
Check distributor and ignition system.
Check operation of oxygen sensors. Check cold start injector±.
Replace oxygen sensors.* Rich malfunction only Check fuel pressure.
Check air flow meter.Check spark plugs.Repair or replace.
Repair air suction.
Repair or replace.
Repair or replace. Repair or replace.
Repair or replace.
Repair or replace. Repair or replace. Try another ECU.
Check injectors.
System normal.Repair air leak.
Repair wiring. BAD
BADBADBADBAD
BADBAD
BAD BADBAD
BAD
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±48
Page 1073 of 2389
Check that there is voltage between ECU terminal +B or +131
and body ground. (IG SW ON)
No voltage between ECU terminals THG and
E2. (IG SW ON)
Check wiring between ECU terminal E1 and body ground.
Check EGR gas temp. sensor.
(See page FI±126)
Check wiring between ECU and
EGR gas temp. sensor.Refer to No. 1.
*(See page FI±34)
Replace EGR gas
temp. sensor.Check EGR system.Repair or replace.
Repair or replace.Repair or replace.
Try another ECU.BAD
BAD
BAD
BAD
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±49
Page 1074 of 2389

EFI SYSTEM CHECK PROCEDURE
(2VZ±FE)
PREPARATION
(a) Disconnect the connectors from the ECU.
(b) Remove the locks as shown in the illustration so that the
tester probe(s) can easily come in.
NOTICE: Pay attention to sections ºAº and ºBº in the il-
lustration which can be easily broken.
(e) Reconnect the connectors to the ECU.
HINT:
wPerform all voltage measurements with the connectors con-
nected.
wVerify that the battery voltage is 11 V or more when the igni-
tion switch is in ºONº position.
Using a voltmeter with high impedance (10 k
/V mini±
mum), measure the voltage at each terminal of the wiring
connectors.
AIR FLOW METER
THROTTLE POSITION SENSOR
Terminals of ECU
No. 1 SPEED SENSOR (Meter side)
No. 2 SPEED SENSOR (AlT side)
THROTTLE POSITION SENSOR FUEL PRESSURE CONTROL VSV
THROTTLE POSITION SENSORCRUISE CONTROL COMPUTER
* 1 w/ ECT
*2 CALIF. only KNOCK CONTROL SENSOR PATTERN SELECT SWITCH
OXYGEN SENSOR HEATER
NEUTRAL START SWITCHEGR GAS TEMP. SENSOR INJECTOR (No. 2 and 3)INJECTOR (No. 4 and 5)
SIFT POSITION SWITCH.
ISC MOTOR NO. 3 COILINJECTOR (No. 1 and 6i
ISC MOTOR NO. 1 COIL
ISC MOTOR NO. 4 COILSIFT POSITION SWITCH ISC MOTOR NO. 2 COILWATER TEMP. SENSORSUB±OXYGEN SENSOR
SIFT POSITION SWITCH COLD START INJECTOR
EFI MAIN RELAY (COIL)
SIFT POSITION SWITCHSUB±OXYGEN SENSOR CHECK CONNECTOR
COMPUTER GROUND
CHECK CONNECTORCHECK CONNECTOR CHECK CONNECTOR
AIR TEMP. SENSORA/C COMPRESSOR
SENSOR GROUNDTerminal Name
OXYGEN SENSOROD MAIN SWITCH
STARTER SWITCHIGNITION SWITCH Terminal Name
AIR FLOW METERTerminal Name
POWER GROUND
POWER GROUND
WARNING LIGHT
EFI MAIN RELAY BRAKE SWITCH
EFt MAIN RELAY ECT SOLENOID
ECT SOLENOIDA/C AMPLIFIER
ECT SOLENOIDDISTRIBUTOR
DISTRIBUTOR DISTRIBUTOR
DISTRIBUTOR
TEMS ECU
TEMS ECU
TEMS ECU Symbol Symbol Symbol
BATTERY IGNITER
IGNITER
*2NSW
*1OD2
No. 30 No. 10
No. 20
*1PWR
*2OX2
M±REL
*1OD 1
*2CHK
*2THGIG SW
*1SP2
BATT
*1SL
*1 DG
1S1THW
*1S2
*1BK
ISC4 1SC2 ISC1
ISC3VTAOX1
ACTS TJSP1
THA
STAKNK EO2 E01
IGT
*1R A/C
EPU
1
L
IGF
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±50