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EC-582Revision: August 2007
DTC P2138 APP SENSOR
2004 QX56
Component InspectionUBS00HCY
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Check voltage between ECM terminals 106 (APP sensor 1 sig-
nal), 98 (APP sensor 2 signal) and ground under the following
conditions.
4. If NG, replace accelerator pedal assembly and go to next step.
5. Perform EC-44, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-44, "
Throttle Valve Closed Position Learning" .
7. Perform EC-44, "
Idle Air Volume Learning" .
Removal and InstallationUBS00HCZ
ACCELERATOR PEDAL
Refer to ACC-2, "ACCELERATOR CONTROL SYSTEM" .
Terminal Accelerator pedal Voltage
106
(Accelerator pedal position
sensor 1)Fully released 0.5 - 1.0V
Fully depressed 4.2 - 4.8V
98
(Accelerator pedal position
sensor 2)Fully released 0.25 - 0.5V
Fully depressed 2.0 - 2.5V
MBIB0023E
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IGNITION SIGNAL
EC-591
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Revision: August 20072004 QX56
5. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Turn ignition switch ON.
4. Check voltage between condenser terminal 1 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector E119.
3. Check harness continuity between IPDM E/R terminal 4 and condenser terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> Go to EC-128, "POWER SUPPLY AND GROUND CIRCUIT" .
NG >> GO TO 7.
7. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E2, F32
Harness for open or short between ignition coil and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0358E
Voltage: Battery voltage
PBIB0624E
Continuity should exist.
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EC-592Revision: August 2007
IGNITION SIGNAL
2004 QX56
8. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between condenser terminal 2 and engine ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9. CHECK CONDENSER
Refer to EC-593, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> Replace condenser.
10. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect ignition coil harness connector.
4. Turn ignition switch ON.
5. Check voltage between ignition coil terminal 3 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E2, F32
Harness for open or short between ignition coil and harness connector F32
>> Repair or replace harness or connectors. Continuity should exist.
Voltage: Battery voltage
BBIA0359E
PBIB0138E
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IGNITION SIGNAL
EC-593
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Revision: August 20072004 QX56
12. CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ignition coil terminal 2 and engine ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to power in harness or connectors.
13. CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ignition coil terminal
1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 14.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
14. CHECK IGNITION COIL WITH POWER TRANSISTOR
Refer to EC-593, "
Component Inspection" .
OK or NG
OK >> GO TO 15.
NG >> Replace ignition coil with power transistor.
15. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00HD3
IGNITION COIL WITH POWER TRANSISTOR
1. Turn ignition switch OFF.
2. Disconnect ignition coil harness connector.
3. Check resistance between ignition coil terminals as follows.
CONDENSER
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.Continuity should exist.
Continuity should exist.
Terminal No. (Polarity) Resistance Ω [at 25°C (77°F)]
1 and 2 Except 0 or ∞
1 and 3
Except 0
2 and 3
PBIB0847E
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INJECTOR CIRCUIT
EC-595
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INJECTOR CIRCUITPFP:16600
Component DescriptionUBS00HD5
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the injector circuit, the coil in the injector is
energized. The energized coil pulls the needle valve back and allows
fuel to flow through the injector into the intake manifold. The amount
of fuel injected depends upon the injection pulse duration. Pulse
duration is the length of time the injector remains open. The ECM
controls the injection pulse duration based on engine fuel needs.
CONSULT-II Reference Value in Data Monitor ModeUBS00HD6
Specification data are reference values.
SEF 3 75 Z
MONITOR ITEM CONDITION SPECIFICATION
B/FUEL SCHDL
Engine: After warming up
Air conditioner switch: OFF
Shift lever: N
No loadIdle 3.0 - 4.2 msec
2,000 rpm 3.0 - 4.2 msec
INJ PULSE-B1
INJ PULSE-B2
Engine: After warming up
Air conditioner switch: OFF
Shift lever: N
No loadIdle 2.0 - 2.8 msec
2,000 rpm 1.9 - 2.9 msec
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INJECTOR CIRCUIT
EC-599
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3. CHECK INJECTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between injector terminal 1 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E2, F32
IPDM E/R connector E119
15A fuse
Harness for open or short between injector and fuse
>> Repair harness or connectors.
5. CHECK INJECTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between injector terminal 2 and ECM terminals 21, 22, 23, 40, 41, 42, 44, 63.
Refer to Wiring Diagram.
4. Also check harness for short to ground and 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.Voltage: Battery voltage
BBIA0374E
PBIB0582E
Continuity should exist.
Page 1795 of 3371
EC-604Revision: August 2007
FUEL PUMP CIRCUIT
2004 QX56
3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E122.
3. Turn ignition switch ON.
4. Check voltage between IPDM E/R terminal 46 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 12.
4. DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between IPDM E/R and ECM
>> Repair harness or connectors.
5. CHECK CONDENSER POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect condenser harness connector.
4. Turn ignition switch ON.
5. Check voltage between condenser terminal 1 and ground with
CONSULT-II or tester.
6. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.Voltage: Battery voltage
PBIB2084E
BBIA0388E
Voltage: Battery voltage should exist for 1 sec-
ond after ignition switch is turned ON.
PBIB0624E
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FUEL PUMP CIRCUIT
EC-605
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Revision: August 20072004 QX56
6. CHECK 15A FUSE
1. Turn ignition switch OFF.
2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse.
7. CHECK CONDENSER POWER SUPPLY CIRCUIT-II FOR OPEN AND SHORT
1. Disconnect IPDM E/R harness connector E119.
2. Check harness continuity between IPDM E/R terminal 13 and condenser terminal 1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between condenser terminal 1 and ground.
Refer to Wiring Diagram.
2. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9. CHECK CONDENSER
Refer to EC-606, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> Replace condenser.
10. CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “fuel level sensor unit and fuel pump” harness con-
nector.
3. Disconnect IPDM E/R harness connector E119.
4. Check harness continuity between IPDM E/R terminal 13 and
“fuel level sensor unit and fuel pump” terminal 1, “fuel level sen-
sor unit and fuel pump” terminal 3 and ground.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.Continuity should exist.
Continuity should exist.
Continuity should exist.
BBIA0583E