2004 INFINITI FX35 ignition

EC-1220
[VK45DE]
DTC P1805 BRAKE SWITCH
Revision: 2004 November 2004 FX35/FX45
DTC P1805 BRAKE SWITCHPFP:25320
DescriptionABS00CDA
Brake switch signal is applied to the ECM through the stop lamp switch when the brake pedal is depressed.
This signal is used mainly to decrease the engine speed when the vehicle is driving.
CONSULT-II Reference Value in Data Monitor ModeABS00CDB
Specification data are reference values.
On Board Diagnosis LogicABS00CDC
The MIL will not light up for this diagnosis.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.
DTC Confirmation ProcedureABS00CDD
WITH CONSULT-II
1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with CONSULT-II.
4. Select “DATA MONITOR” mode with CONSULT-II.
5. If 1st trip DTC is detected, go to EC-1222, "
Diagnostic Proce-
dure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1805
1805Brake switchA brake switch signal is not sent to ECM for
extremely long time while the vehicle is driving.

Harness or connectors
(Stop lamp switch circuit is open or
shorted.)

Stop lamp switch
Engine operating condition in fail-safe mode
ECM controls the electric throttle control actuator by regulating the throttle opening to a small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
SEF058Y

EC-1222
[VK45DE]
DTC P1805 BRAKE SWITCH
Revision: 2004 November 2004 FX35/FX45
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.
Diagnostic ProcedureABS00CDF
1. CHECK STOP LAMP SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Check the stop lamp when depressing and releasing the brake pedal.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Disconnect stop lamp switch harness connector.
2. Check voltage between stop lamp switch terminal 1 and ground
with CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
101 P/L Stop lamp switch[Ignition switch: OFF]

Brake pedal: Fully releasedApproximately 0V
[Ignition switch: OFF]

Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
Brake pedal Stop lamp
Fully released Not illuminated
Slightly depressed Illuminated
PBIB1506E
Voltage: Battery voltage
PBIB1184E

DTC P1805 BRAKE SWITCH
EC-1223
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
3. DETECT MALFUNCTIONING PART
Check the following.

10A fuse

Fuse block (J/B) connector E201

Joint connector-2

Harness for open and short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect stop lamp switch harness connector.
4. Check harness continuity between ECM terminal 101 and stop
lamp switch terminal 2.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E211, M41

Joint connector-2

Harness for open or short between ECM and stop lamp switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK STOP LAMP SWITCH
Refer to EC-1224, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace stop lamp switch.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.
PBIB1506E

DTC P2122, P2123 APP SENSOR
EC-1225
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P2122, P2123 APP SENSORPFP:18002
Component DescriptionABS00CDH
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeABS00CDI
Specification data are reference values.
*: Accelerator pedal position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage.
On Board Diagnosis LogicABS00CDJ
These self-diagnoses have the one trip detection logic.
NOTE:
If DTC P2122 or P2123 is displayed with DTC P1229, first perform the trouble diagnosis for DTC P1229.
Refer to EC-1156
.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB1741E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN1

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.7V
ACCEL SEN2*

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
CLSD THL POS

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2122
2122Accelerator pedal posi-
tion sensor 1 circuit low
inputAn excessively low voltage from the APP sen-
sor 1 is sent to ECM.

Harness or connectors
(APP sensor 1 circuit is open or
shorted.)

Accelerator pedal position sensor
(Accelerator pedal position sensor 1) P2123
2123Accelerator pedal posi-
tion sensor 1 circuit high
inputAn excessively high voltage from the APP sen-
sor 1 is sent to ECM.
Engine operating condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.

EC-1226
[VK45DE]
DTC P2122, P2123 APP SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS00CDK
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.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-1228, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF058Y

EC-1228
[VK45DE]
DTC P2122, P2123 APP SENSOR
Revision: 2004 November 2004 FX35/FX45
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.
Diagnostic ProcedureABS00CDM
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
82 B/WSensor ground
(APP sensor 1/Steering
switch)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
83 G/ORSensor ground
(APP sensor 2)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
90 L/BSensor power supply
(APP sensor 1)[Ignition switch: ON]Approximately 5V
91 GSensor power supply
(APP sensor 2)[Ignition switch: ON]Approximately 5V
98 B/PAccelerator pedal position
sensor 2[Ignition switch: ON]

Engine stopped

Accelerator pedal is fully released0.15 - 0.60V
[Ignition switch: ON]

Engine stopped

Accelerator pedal is fully depressed1.95 - 2.40V
106 R/BAccelerator pedal position
sensor 1[Ignition switch: ON]

Engine stopped

Accelerator pedal is fully released0.5 - 1.0V
[Ignition switch: ON]

Engine stopped

Accelerator pedal is fully depressed3.9 - 4.7V
PBIB2195E

DTC P2122, P2123 APP SENSOR
EC-1229
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
2. CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor harness
connector.
2. Turn ignition switch ON.
3. Check voltage between APP sensor terminal 6 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E211, M41

Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK APP SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between APP sensor terminal 3 and ECM terminal 82.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E211, M41

Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB1548E
Voltage: Approximately 5V
PBIB0914E
Continuity should exist.

EC-1230
[VK45DE]
DTC P2122, P2123 APP SENSOR
Revision: 2004 November 2004 FX35/FX45
6. CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 106 and APP sensor terminal 5.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E211, M41

Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK APP SENSOR
Refer to EC-1253, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-698, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-698, "
Throttle Valve Closed Position Learning" .
4. Perform EC-698, "
Idle Air Volume Learning" .
>>INSPECTION END
10. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionABS00CDN
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.Continuity should exist.
Terminal Accelerator pedal Voltage
106
(Accelerator pedal position
sensor 1)Fully released 0.5 - 1.0V
Fully depressed 3.9 - 4.7V
98
(Accelerator pedal position
sensor 2)Fully released 0.15 - 0.60V
Fully depressed 1.95 - 2.40V
MBIB0023E