ignition INFINITI QX4 2005 Factory Service Manual

EC-618Revision: October 2005
DTC P2138 APP SENSOR
2005 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-90, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-90, "
Throttle Valve Closed Position Learning" .
7. Perform EC-91, "
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

IGNITION SIGNAL
EC-619
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EC
Revision: October 20052005 QX56
IGNITION SIGNALPFP:22448
Component DescriptionUBS00L1A
IGNITION COIL & POWER TRANSISTOR
The ignition signal from the ECM is sent to and amplified by the power transistor. The power transistor turns
ON and OFF the ignition coil primary circuit. This ON/OFF operation induces the proper high voltage in the coil
secondary circuit.
BBIA0359E

EC-620Revision: October 2005
IGNITION SIGNAL
2005 QX56
Wiring DiagramUBS00L1B
BBWA1710E

IGNITION SIGNAL
EC-621
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EC
Revision: October 20052005 QX56
Specification data are reference values and are measured between each terminal and ground.
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120BR
BRPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)

EC-622Revision: October 2005
IGNITION SIGNAL
2005 QX56
BBWA2488E

IGNITION SIGNAL
EC-623
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EC
Revision: October 20052005 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.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
46
60
61
62L/R
GR/R
O/W
Y/RIgnition signal No. 7
Ignition signal No. 5
Ignition signal No. 3
Ignition signal No. 1[Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle.0 - 0.2V
[Engine is running]

Warm-up condition

Engine speed: 2,000 rpm.0.1 - 0.4V
PBIB0044E
PBIB0045E

EC-624Revision: October 2005
IGNITION SIGNAL
2005 QX56
BBWA1712E

IGNITION SIGNAL
EC-625
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EC
Revision: October 20052005 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 ProcedureUBS00L1C
1. CHECK ENGINE START
Turn ignition switch OFF, and restart engine.
Is engine running?
Ye s o r N o
Yes (With CONSULT-II)>>GO TO 2.
Yes (Without CONSULT-II)>>GO TO 3.
No >> GO TO 4.
2. CHECK OVERALL FUNCTION
With CONSULT-II
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode with
CONSULT-II.
2. Make sure that each circuit produces a momentary engine
speed drop.
OK or NG
OK >>INSPECTION END
NG >> GO TO 10.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
65
79
80
81G/R
V/W
W/R
W/GIgnition signal No. 8
Ignition signal No. 6
Ignition signal No. 4
Ignition signal No. 2[Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle.0 - 0.2V
[Engine is running]

Warm-up condition

Engine speed: 2,000 rpm.0.1 - 0.4V
PBIB0044E
PBIB0045E
PBIB0133E

EC-626Revision: October 2005
IGNITION SIGNAL
2005 QX56
3. CHECK OVERALL FUNCTION
Without CONSULT-II
1. Let engine idle.
2. Read the voltage signal between ECM terminals 46, 60, 61, 62,
65, 79, 80, 81 and ground with an oscilloscope.
3. Verify that the oscilloscope screen shows the signal wave as
shown below.
NOTE:
The pulse cycle changes depending on rpm at idle.
OK or NG
OK >>INSPECTION END
NG >> GO TO 10.
4. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
2. Check voltage between ECM terminals 119, 120 and ground
with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> Go to EC-157, "
POWER SUPPLY AND GROUND CIR-
CUIT" .
PBIB2094E
PBIB0044E
Voltage: Battery voltage
MBIB0034E

IGNITION SIGNAL
EC-627
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EC
Revision: October 20052005 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-157, "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.