1986 TOYOTA CAMRY V20 ECU

Check that there is voltage between ECU terminal +B (+B1)
and body ground. (IG SW ON)There is no voltage between ECU terminals IDL and E2. (IG SW
ON) (Throttle valve open)
Check wiring between ECU terminal E 1 and body
ground.
Check wiring between ECU and
throttle position sensor. Check throttle position sensor.
(See page FI±112)
Repair or replace throttle
position sensor.Throttle valve fully closed
Refer to No. 1.
(See page FI±51) Throttle valve fully openThrottle valve open
Repair or replace.
Repair or replace.
Try another ECU. Try another ECU.
wIDL ± E2
STD voltage
No voltage
IG SW ON Terminals
Condition Trouble
BAD
BADBAD
BAD
No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±55

Check that there is voltage between ECU terminal VC and E2.
(IG SW ON) Check that there is voltage between ECU terminal +B (+B1)
and body ground. (IG SW ON)
There is no specified voltage at ECU terminals VTA and E2.
(1O SW ON) There is 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±112)
Check throttle position sensor.
(See page FI±112) Refer to VC ± E2 trouble
section.Repair or replace
wiring. Refer to No. 1.
(See page FI±51 )
Repair or replace.
Repair or replace.
Repair or replace.
Try another ECU. Try another ECU.
wVTA ± E2 wVC ± E2
BAD
BAD BAD
BAD
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±56

Check that there is voltage between ECU terminal +B (+Bl)
and body ground. (IG SW ON) There is no voltage between ECU terminals VC or VS and E2.
(IG SW ON)
Check wiring between ECU terminal E 1 and body ground.
Check wiring between ECU and air flow
meter. Check air flow meter.
(See page FI±104)
Measuring plate fully closed
Refer to No. 1.
(See page FI±52) Measuring plate fully open
Replace air flow
meter.Repair or replace.
Repair or replace.
Try another ECU.STD voltage
No voltage
3,000 rpmIG SW ON TerminalsCondition
Trouble
Idling
¿ OK
BAD
BAD BAD No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±57

There is no voltage between ECU terminal No. 10, No. 20
and/or No. 30 and E41 and/or E02. (IG SW ON)
Check that there is voltage between ECU terminal No. 10,
No. 20 or No. 30 and body ground.
Check wiring between ECU terminal E01 and/or
E02 and body ground.
Check resistance of magnetic coil in each injector.
STD resistance: Approx. 13.8

Check wiring between ECU
terminal No. 10, No. 20 and/or
No. 30 and battery.Check fusible link and
ignition switch.Repair or replace.
Try another ECU.
Repair or replace. Repair or replace.
Replace injector.STD voltage
No voltage
IG SW ON
Terminals
Condition Trouble
No.
BADBAD
BAD
BAD
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±58

Check that there is voltage between ECU terminal +B (+B1 )
and body ground. (IG SW ON)There is no voltage between ECU terminals THA and E2.
(IG SW ON)
Check wiring between ECU terminal E1 and body ground.
Check wiring between ECU and air temp.
sensor. Intake air temperature 20°C (68°F)
Check air temp. sensor.
(See page FI±104)Refer to No. 1.
(See page FI±52)
Replace air flow
meter.Repair or replace.
Repair or replace.
Try another ECU.STD voltage
No voltage
IG SW ON
TerminalsCondition Trouble
BADBAD
BAD No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±59

Check that there is voltage between ECU terminal +B (+B1)
and body ground. (IG SW ON) There is no voltage between ECU terminals THW and E2.
(IG SW ON)
Check wiring between ECU and water temp.
sensor. Check wiring between ECU terminal E1 and body ground.
Check water temp. sensor.
(See page FI±125) Coolant temperature 80°C
(176°F)
Refer to No. 1.
(See page FI±52)
Replace water
temp. sensor.
Repair or replace.Repair or replace.
Try another ECU.STD voltage
No voltageIG SW ON Terminals
Condition
Trouble
BADBAD
BAD No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±60

Check that there is voltage at STA (50) terminal of starter.
(IG SW START) STD voltage: 6 ± 14 VThere is no voltage between ECU terminals STA and El.
(IG SW START)
Check wiring between ECU terminal E1 and body ground.
Check fusible links, battery, wiring,
ignition switch and neutral start switch. .Check wiring between ECU terminal STA
and ignition switch terminal ST1 .
Check wiring between ignition switch terminal
ST1 and starter terminal STA (50) Check starter
operation.
. Repair or replace.Repair or replace.
Try another ECU.
Repair or replace.
Check starter.STD voltage
No voltage TerminalsCondition
Cranking Trouble
BAD BAD
BAD
BAD No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±61

Check that there is voltage between ECU terminal IGT and body
ground. (idling) There is no voltage between ECU terminals IGT and El.
(idling)
Check wiring between ECU and
battery.Check fusible link and ignition
switch.Check wiring between ECU
terminal E 1 and body ground.
Check distributor. (See page IG±8)
Repair or replace.
Repair or replace.Repair or replace.Repair or replace.
Try another ECU.
Repair or
replace.
Check igniter.STD voltage
No voltage Terminals
Condition Trouble
Idling
BAD
BAD
BADBAD
BAD No.
± EFI SYSTEMTroubleshooting with Volt OhmmeterFI±62