DTC P1122 ELECTRIC THROTTLE CONTROL FUNCTION
EC-371
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Revision: August 20072004 QX56
6. CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT-II
1. Disconnect ECM harness connector.
2. Disconnect IPDM E/R harness connector E122.
3. Check harness continuity between ECM terminal 104 and IPDM E/R terminal 47.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK FUSE
1. Disconnect 20A fuse.
2. Check 20A fuse for blown.
OK or NG
OK >> GO TO 8.
NG >> Replace 20A fuse.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace IPDM E/R. Refer to PG-17, "IPDM E/R (INTELLIGENT POWER DISTRIBUTION MOD-
ULE ENGINE ROOM)" .
NG >> Repair or replace harness or connectors.
9. CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Turn ignition switch OFF.
2. Disconnect electric throttle control actuator harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 10.
NG >> Repair or replace.Continuity should exist.
Electric throttle control
actuator terminalECM terminal Continuity
55 Should not exist
4 Should exist
6 5 Should exist
4 Should not exist
PBIB1480E
DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAY
EC-373
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Revision: August 20072004 QX56
DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAYPFP:16119
Component DescriptionUBS00H7P
Power supply for the throttle control motor is provided to the ECM via throttle control motor relay. The throttle
control motor relay is ON/OFF controlled by the ECM. When the ignition switch is turned ON, the ECM sends
an ON signal to throttle control motor relay and battery voltage is provided to the ECM. When the ignition
switch is turned OFF, the ECM sends an OFF signal to throttle control motor relay and battery voltage is not
provided to the ECM.
CONSULT-II Reference Value in Data Monitor ModeUBS00H7Q
Specification data are reference values.
On Board Diagnosis LogicUBS00H7R
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MlL lights up.
DTC Confirmation ProcedureUBS00H7S
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR DTC P1124
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V when engine
is running.
With CONSULT-II
1. Turn ignition switch ON and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If DTC is detected, go to EC-376, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
MONITOR ITEM CONDITION SPECIFICATION
THRTL RELAY
Ignition switch: ON ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1124
11 2 4Throttle control motor
relay circuit shortECM detect the throttle control motor
relay is stuck ON.
Harness or connectors
(Throttle control motor relay circuit is shorted)
Throttle control motor relay
P1126
11 2 6Throttle control motor
relay circuit openECM detects a voltage of power source
for throttle control motor is excessively
low.
Harness or connectors
(Throttle control motor relay circuit is open)
Throttle control motor relay
Engine operating condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return
spring.
SEF 0 58 Y
DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAY
EC-377
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Revision: August 20072004 QX56
4. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I
1. Check voltage between ECM terminal 3 and ground under the
following conditions with CONSULT-II or tester.
OK or NG
OK >> GO TO 7.
NG >> GO TO 5.
5. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect IPDM E/R harness connector E119.
4. Check continuity between ECM terminal 3 and IPDM E/R terminal 6.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E2, F32
Harness for open or short between ECM and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace IPDM E/R. Refer to PG-17, "IPDM E/R (INTELLIGENT POWER DISTRIBUTION MOD-
ULE ENGINE ROOM)" .
NG >> Repair or replace harness or connectors.
Ignition switch Voltage
OFF Approximately 0V
ONBattery voltage
(11 - 14V)
MBIB0028E
Continuity should exist.
EC-380Revision: August 2007
DTC P1128 THROTTLE CONTROL MOTOR
2004 QX56
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnostic ProcedureUBS00H7Z
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-133, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
4L/WThrottle control motor
(Close)[Ignition switch: ON]
Engine stopped
Shift lever: D
Accelerator pedal: Released0 - 14V
5L/BThrottle control motor
(Open)[Ignition switch: ON]
Engine stopped
Shift lever: D
Accelerator pedal: Fully depressed0 - 14V
PBIB1104E
PBIB1105E
BBIA0354E
EC-384Revision: August 2007
DTC P1146, P1166 HO2S2
2004 QX56
DTC Confirmation ProcedureUBS00H85
NOTE:
If DTC confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1146” or “HO2S2 (B2) P1166” of “HO2S2” in “DTC WORK SUPPORT” mode with
CONSULT-II.
9. Start engine and following the instruction of CONSULT-II.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to EC-389, "
Diagnostic Procedure" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckUBS00H86
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 55 [HO2S2 (B1) signal] or 74 [HO2S2 (B2) signal] and
ground.
SEF 1 74 Y
PBIB0818E
EC-392Revision: August 2007
DTC P1146, P1166 HO2S2
2004 QX56
5. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal and HO2S2 terminal as follows.
Refer to Wiring Diagram.
3. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
4. Also check harness for short to ground or short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK HEATED OXYGEN SENSOR 2
Refer to EC-392, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning heated oxygen sensor 2.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00H89
HEATED OXYGEN SENSOR 2
With CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
DTCTe r m i n a l s
Bank
ECM Sensor
P1146 55 1 1
P1166 74 1 2
Continuity should exist.
DTCTe r m i n a l s
Bank
ECM Sensor
P1146 55 1 1
P1166 74 1 2
Continuity should not exist.
SEF 1 74 Y
DTC P1146, P1166 HO2S2
EC-393
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Revision: August 20072004 QX56
6. Select “FUEL INJECTION” in “ACTIVE TEST” mode, and select
“HO2S2 (B1)/(B2)” as the monitor item with CONSULT-II.
7. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to ±25%.
“HO2S2 (B1)/(B2)” should be above 0.70V at least once when the “FUEL INJECTION” is +25%.
“HO2S2 (B1)/(B2)” should be below 0.18V at least once when the “FUEL INJECTION” is −25%.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Without CONSULT-II
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 55 [HO2S2 (B1) signal] or 74 [HO2S2 (B2) signal] and
ground.
6. Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.70V at least once during this
procedure.
If the voltage is above 0.70V at step 6, step 7 is not neces-
sary.
7. Keep vehicle at idling for 10 minutes, then check voltage. Or
check the voltage when coasting from 80 km/h (50 MPH) in D
position.
The voltage should be below 0.18V at least once during this
procedure.
8. If NG, replace heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m
(19.7 in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
PBIB1672E
PBIB1210E
PBIB2054E
EC-396Revision: August 2007
DTC P1147, P1167 HO2S2
2004 QX56
DTC Confirmation ProcedureUBS00H8E
NOTE:
If DTC confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1147” or “HO2S2 (B2) P1167” of “HO2S2” in “DTC WORK SUPPORT” mode with
CONSULT-II.
9. Start engine and following the instruction of CONSULT-II.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to EC-401, "
Diagnostic Procedure" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckUBS00H8F
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 55 [HO2S2 (B1) signal] or 74 [HO2S2 (B2) signal] and
ground.
SEF 1 74 Y
PBIB0819E