1997 TOYOTA SUPRA check engine

A00393
ON
3
445
65
B
B
ECM
5V
THA
E2 Intake Air
Temp. Sensor
A00691
ON
ECM
5V
THA
E2 Intake Air
Temp. Sensor
ECM
B Connector
DI-178
- DIAGNOSTICSENGINE (2JZ-GTE)
406 Author
: Date
:
1997 SUPRA (RM502U)
4 Check for short in harness and ECM.
PREPARATION:
(a) Disconnect the mass air flow meter connector.
(b) Turn ignition switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA
hand-held tester.
OK:
Temperature value: - 40°C (- 40°F).
OK Replace mass air flow meter.
NG
5 Check for short in harness or ECM.
PREPARATION:
(a) Disconnect the B connector from ECM
(See page DI-164).
HINT:
Mass air flow meter connector is disconnected.
(b) Turn ignition switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA
hand-held tester.
OK:
Temperature value: - 40°C (- 40°F)
OK Repair or replace harness or connector.
NG
Check and replace ECM (See page IN-28).

BE6653FI7057A06715
ON
Engine Coolant
Temp. Sensor
2
144
65ECM
5V
THW
E2
BB
DI-180
- DIAGNOSTICSENGINE (2JZ-GTE)
408 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
HINT:

If DTC ºP0110º (Intake Air Temp. Circuit Malfunction), ºP0115º (Engine Coolant Temp. Circuit Malfunc-
tion), ºP0120º (Throttle/Pedal Position Sensor/Switch ºAº Circuit Malfunction) are output simulta-
neously, E2 (sensor ground) may be open.
1 Connect the OBD II scan tool or TOYOTA hand-held tester, and read value of en-
gine coolant temperature.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(b) Turn ignition switch ON and push the OBD II scan tool or TOYOTA hand-held tester main switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA hand-held tester.
OK:
Same as actual engine coolant temperature.
HINT:

If there is open circuit, OBD II scan tool or TOYOTA hand-held tester indicates - 40°C (- 40°F).

If there is short circuit, OBD II scan tool or TOYOTA hand-held tester indicates 140°C (284°F) or more.
NG - 40°C ( - 40°F) .............. Go to step 2.
140°C (284°F) or more .... Go to step 4.
OK
Check for intermittent problems
(See page DI-147).
2 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect the engine coolant temp. sensor connector.
(b) Connect sensor wire harness terminals together.
(c) Turn ignition switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA
hand-held tester.
OK:
Temperature value: 140°C (284°F) or more
OK Confirm good connection at sensor. If OK,
replace engine coolant temp. sensor.
NG

BE6653FI7055P23923A06716
ON
Engine Coolant
Temp. Sensor
2
144
65ECM
5V
THW
E2
BB
Check Harness A
ECM
B65, 44
THW
E2
A00216
ON
Engine Coolant
Temp. SenosrECM
44
655V
THW
E2
BB
- DIAGNOSTICSENGINE (2JZ-GTE)
DI-181
409 Author
: Date
:
1997 SUPRA (RM502U)
3 Check for open in harness or ECM.
PREPARATION:
(a) Connect Check Harness A (See page DI-164).
(b) Connect between terminals THW and E2 of ECM connec-
tor.
HINT:
Engine coolant temp. sensor connector is disconnected. Be-
fore checking, do a visual and contact pressure check for the
ECM connector (See page IN-28).
(c) Turn ignition switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA
hand-held tester.
OK:
Temperature value: 140°C (284°F) or more
OK Open in harness between terminals E2 or THW,
repair or replace harness.
NG
Confirm good connection at ECM.
If OK, replace ECM.
4 Check for short in harness and ECM.
PREPARATION:
(a) Disconnect the engine coolant temp. sensor connector.
(b) Turn ignition switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA
hand-held tester.
OK:
Temperature value: - 40°C (- 40°F)
OK Replace engine coolant temp. sensor.
NG

BE6653FI7056P25067A06717
ON
Engine Coolant
Temp. SensorECM
5V
THW
E2
ECM
B Connector
DI-182
- DIAGNOSTICSENGINE (2JZ-GTE)
410 Author
: Date
:
1997 SUPRA (RM502U)
5 Check for short in harness or ECM.
PREPARATION:
(a) Disconnect the B connector of ECM (See page DI-164).
HINT:
Engine coolant temp. sensor connector is disconnected.
(b) Turn ignition switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA
hand-held tester.
OK:
Temperature value: - 40°C (- 40°F)
OK Repair or replace harness or connector.
NG
Check and replace ECM (See page IN-28).

- DIAGNOSTICSENGINE (2JZ-GTE)
DI-183
411 Author
: Date
:
1997 SUPRA (RM502U)
DTC P0116 Engine Coolant Temp. Circuit Range/
Performance Problem
CIRCUIT DESCRIPTION
Refer to ºEngine Coolant Temp. Circuit Malfunctionº on page DI-179.
DTC No.DTC Detecting ConditionTrouble Area
When the engine starts, the water temp. is -7°C (20°F) or
less. And, 20 min. or more after the engine starts, the engine
coolant temp. sensor value is 20°C (68°F) or less
(2 trip detection logic)
P0116
When the engine starts, the water temp. is between -7°C
(20°F) and 10°C (50°F). And, 5 min. or more after the engine
starts, the engine coolant temp. sensor value is 20°C (68°F) or
less
(2 trip detection logic)

Engine coolant temp. sensor

Cooling system
When the engine starts, the water temp. is 10°C (50°F) or
more. And, 2 min. or more after the engine starts, the engine
coolant temp. sensor value is 20°C (68°F) or less
(2 trip detection logic)
INSPECTION PROCEDURE
HINT:
If DTC ºP0115º (Engine Coolant Temp. Circuit Malfunction) and ºP0116º (Engine Coolant Temp. Circuit
Range/Performance) are output simultaneously, engine coolant temp. sensor circuit may be open.
Perform troubleshooting of DTC P0115 first.
1 Are there any other codes (besides DTC P0116) being output?
YES Go to relevant DTC chart.
NO
2 Check thermostat (See page CO-15).
NG Replace thermostat.
OK
Replace engine coolant temp. sensor.
DI4SQ-01

FI7052
A00694
ON
1(+)
DI-186
- DIAGNOSTICSENGINE (2JZ-GTE)
414 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
HINT:
If DTC P0110, P0115 and P0120 are output simultaneously, E2 (sensor ground) may be open.
1 Connect the OBD II scan tool or TOYOTA hand-held tester and read the throttle
valve opening percentage.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC 3.
(b) Turn ignition switch ON and push the OBD II scan tool or TOYOTA hand-held tester main switch ON.
CHECK:
Read the throttle valve opening percentage.
OK:
Throttle valveThrottle valve opening position ex-
pressed as percentage
Fully openApprox. 70 %
Fully closedApprox. 10 %
OK Check for intermittent problems
(See page DI-147).
NG
2 Check voltage between terminal 1 of wire harness side connector and body
ground.
PREPARATION:
(a) Disconnect the throttle position sensor connector.
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminal 1 of wire harness side con-
nector and body ground.
OK:
Voltage: 4.5 - 5.5 V
NG Go to step 5.
OK

P24693
4
2
1
A00695
ONCheck Harness A
ECM
B65, 43
VTA1 (+)
E2 (-)
- DIAGNOSTICSENGINE (2JZ-GTE)
DI-187
415 Author
: Date
:
1997 SUPRA (RM502U)
3 Check throttle position sensor.
PREPARATION:
Disconnect the throttle position sensor connector.
CHECK:
Measure resistance between terminals 1, 2 and 4 of throttle
position sensor.
OK:
TerminalsThrottle valveResistance
1 - 4-3.1 - 7.2 kW
24Fully closed0.34 - 6.3 kW2 - 4Fully open2.4 - 11.2 kW
NG Replace throttle position sensor
(See page SF-44).
OK
4 Check voltage between terminals VTA1 and E2 of ECM.
PREPARATION:
(a) Connect Check Harness A (See page DI-164).
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminals VTA1 and E2 of ECM.
OK:
Throttle ValveVoltage
Fully closed0.3 - 0.8 V
Fully open3.2 - 4.9 V
NG Check for open and short in harness and con-
nector between ECM and throttle position sen-
sor (VTA line) (See page IN-28).
OK
Check and replace ECM (See page IN-28).

A00696
ONCheck Harness A
ECM
B65, 41
VCC (+)
E2 (-)
DI-188
- DIAGNOSTICSENGINE (2JZ-GTE)
416 Author
: Date
:
1997 SUPRA (RM502U)
5 Check voltage between terminals VCC and E2 of ECM.
PREPARATION:
(a) Connect Check Harness A (See page DI-164).
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminals VCC and E2 of ECM con-
nector.
OK:
Voltage 4.5 - 5.5 V
NG Check and replace ECM (See page IN-28).
OK
Check for open in harness and connector be-
tween ECM and sensor (VC line)
(See page IN-28).