1986 TOYOTA SUPRA Service Repair Manual

(1) Remove VSV.
(2) Disconnect VSV connector.
(1) Measure resistance between terminals.
(2) Measure resistance between each terminal
and the body.
(1) Resistance: 38 Ð 44
at 20°C (68°F)
(2) Resistance: 1 M
or higher
Check operation of VSV when battery positive volt-
age is applied and released to the VSV terminals.
Battery positive voltage is applied:
Air from port E is flowing out through port F.
Battery positive voltage is not applied:
Air from port E is flowing out through the air fil-
ter.
Check VSV for Exhaust Gas Control Valve
Replace VSV for exhaust gas control valve.
EG±592± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(1) Remove VSV.
(2) Disconnect VSV connector.
(1) Measure resistance between terminals.
(2) Measure resistance between each terminal
and the body.
(1) Resistance: 38.5 Ð 44.5
at 20°C (68°F)
(2) Resistance: 1 M
or higher
Check operation of VSV when battery positive volt-
age is applied and released to the VSV terminals.
Battery positive voltage is applied:
Air from port E is flowing out through port F.
Battery positive voltage is not applied:
Air from port E is flowing out through the air
filter.
Check VSV for Intake Air Control Valve
Replace VSV for intake gas control valve.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±593

(See page EG±510)
(See page IN±30).
(1) Connect SST (check harness ªAº).
(See page EG±510)
(2) Turn ignition switch ON.
Measure voltage between terminal VSV1, VSV2,
VSV3 of engine control module connector and
body ground.
Voltage: 9 Ð 14 V
Check voltage between terminal VSV1, VSV2, VSV3 of engine control
module connector and body ground.
Check actuator. (See page EG±144, 158)
Repair or replace harness or connector.
Check for open and short in harness and connector between EFI main replay
and engine control module (See page IN±30).
Check and replace engine control module. EG±594
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

VSV Circuit for Fuel Pressure Control
CIRCUIT DESCRIPTION
The ECM turns on a VSV (Vacuum Switching
Valve) to draw air into the diaphragm chamber
of the pressure regulator if it detects that the
temperature of the engine coolant is too high
during engine starting.
The air drawn into the chamber increases the
fuel pressure to prevent fuel vapor lock at high
engine temperature in order to help the en-
gine start when it is warm.
Fuel pressure control ends approx. 120 sec.
after the engine is started.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±595

INSPECTION PROCEDURE
(1) Remove VSV.
(2) Disconnect VSV connector.
(1) Measure resistance between terminals.
(2) Measure resistance between each terminal
and the body.
(1) Resistance: 33 Ð   at 20°C (68°F)
(2) Resistance: 1 M or higher
Check operation of VSV when battery positive volt-
age is applied and released to the VSV terminals.
Battery positive voltage is applied:
Air from port E is flowing out through the air fil-
ter.
Battery positive voltage is not applied:
Air from port E is flowing out through port G.
Check VSV for fuel pressure control.
Replace VSV for fuel pressure control.
EG±596± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page IN±30).
(1) Connect SST (check harness ªAº).
(See page EG±510)
SST 09990±01000
(2) Turn ignition switch ON.
Measure voltage between terminal FPU of engine
control module connector and body ground.
Voltage: 9 Ð 14 V
Check voltage between terminal FPU of engine control module
connector and body ground.
Proceed to next circuit inspection shown
on matrix chart (See page Eg±514).
Repair or replace harness or connector.
Check for open and short in harness and connector between engine control
module and VSV, VSV and EFI main relay (See page IN±30).
Check and replace engine control module.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±597

TE1 TE2 Terminal Circuit
CIRCUIT DESCRIPTION
Terminal TE1 is located in data link connectors 1 and 2. Terminal TE2 is located ONLY in data link connector
2.
The data link connector 1 is located in the engine compartment and the data link connector 2 is located in the
cabin. When these terminals are connected with the E1 terminal, diagnostic trouble codes in normal mode or
test mode can be read from the malfunction indicator lamp on the telltale light RH. EG±598
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page IN±30).
Turn ignition switch ON.
(1) For DLC1, measure voltage between terminal
TE1 and E1.
(2) For DLC2 measure voltage between terminals
TE1, TE2 and E1.
Voltage: 9 Ð 14 V
Check voltage between terminals TE1, TE2 and E1 of data link connectors
1 and 2.
Check and replace engine control module.
Repair or replace harness or connector.
Check for open and short in harness and connector between engine control
module and data link connectors 1, 2 (See page IN±30).
Repair or replace harness or connector.
Check and replace engine control module.
Check continuity between terminal E1 of data link connectors 1, 2 and
body ground.
INSPECTION PROCEDURE
HINT: If terminals TE1 and TE2 are connected with terminal E1, diagnostic trouble code is not output or test
mode is not activated.
Even though terminal TE1 is not connected with terminal E1, the malfunction indicator lamp blinks.
For the above phenomenon, the likely cause is an open or short in the wire harness, or malfunction inside
the ECM.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±599