2008 INFINITI FX35 AUX

DTC P1721 VEHICLE SPEED SENSOR MTRAT-137
< SERVICE INFORMATION >
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DTC P1721 VEHICLE SPEED SENSOR MTR
DescriptionINFOID:0000000001327241
The vehicle speed sensor-MTR signal is transmitted from unified meter and A/C amp. to TCM by CAN com-
munication line. The signal functions as an auxiliary device to the revolution sensor when it is malfunctioning.
The TCM will then use the vehicle speed sensor·MTR signal.
CONSULT-III Reference Val ue in Data Monitor ModeINFOID:0000000001327242
On Board Diagnosis LogicINFOID:0000000001327243
Diagnostic trouble code “P1721 VEH SPD SE/CIR-MTR” wi th CONSULT-III is detected when TCM does not
receive the proper vehicle speed sensor MTR signal (i nput by CAN communication) from combination meter.
Possible CauseINFOID:0000000001327244
Harness or connectors
(Sensor circuit is open or shorted.)
DTC Confirmation ProcedureINFOID:0000000001327245
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, alw ays turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITO R” mode for “TRANSMISSION” with CONSULT-III.
3. Touch “START”.
4. Start engine and maintain the following conditions for at least 5 consecutive seconds. ACCELE POSI: 1.0/8 or less
VHCL/S SE-MTR: 30 km/h (17 MPH) or more
5. If DTC is detected, go to AT-137, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001327246
1.CHECK CAN COMMUNICATION LINE
With CONSULT-III
 Perform the self-diagnosis.
Without CONSULT-III
 Perform the self-diagnosis. Refer to AT-91, "
Diagnosis Procedure without CONSULT-III".
Is malfunction in the CAN communication indicated in the result?
YES >> Check CAN communication line. Refer to AT- 9 4.
NO >> GO TO 2.
2.CHECK INPUT SIGNAL
With CONSULT-III
1. Start engine.
2. Select “ECU INPUT SIGNALS” in “DATA MONITO R” mode for “TRANSMISSION” with CONSULT-III.
3. Drive vehicle and read out the value of “VHCL/S SE-MTR”.
Item name Condition Display value
VHCL/S SE-MTR During driving Approximately matches the speedometer reading.
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ATC-44
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Shifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing (fan) UP switch.
FUNCTION CONFIRMATION PROCEDURE
1.SET IN SELF-DIAGNOSIS MODE
1. Turn ignition switch ON.
2. Set in self-diagnosis mode as follows. Within 10 seconds after starting engine (ignition switch is turned ON.), press OFF switch for at least 5 seconds.
NOTE:
 If battery voltage drops below 12 V during diagnosis STEP-3, door motor speed becomes slower and as a
result, the system may generate an error even when operation is normal. To avoid this, start engine before
performing this diagnosis.
 Former STEP-1 (LEDs and display screen are checked) does not exist in this self-diagnosis function.
>> GO TO 2.
2.STEP-2: SENSOR CIRCUITS ARE CHECK ED FOR OPEN OR SHORT CIRCUIT
SJIA1571E
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ATC-46
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Refer to the following chart and check discharge air flow, air temper-
ature, blower motor duty ratio and compressor operation.
Checks must be made visually, by listening the sound, or by touching air outlets with hand, etc. for improper
operation.
*1: FOOT position during automatic control. Refer to "AUXILIARY MECHANISM: FOOT POSITION SETTING
TRIMMER".
OK or NG
OK >> GO TO 8.
NG >>  Air outlet does not change.
Go to Mode Door Motor Circuit. Refer to ATC-57, "
Mode Door Motor Circuit".
 Intake door does not change. Go to Intake Door Motor Circuit. Refer to ATC-62, "
Intake Door Motor Circuit".
 Discharge air temperature does not change. Go to Air Mix Door Motor Circuit. Refer to ATC-59, "
Air Mix Door Motor Circuit".
 Blower motor operation is malfunctioning.
Go to Blower Motor Circuit. Refer to ATC-64, "
Blower Motor Circuit".
 Magnet clutch does not engage. Go to Magnet Clutch Circuit. Refer to ATC-69, "
Magnet Clutch Circuit".
8.STEP-5: TEMPERATURE OF EACH SENSOR IS CHECKED
1. Press temperature control (UP) switch (driver side).
2. Code No. 51 appears on the display.
>> GO TO 9.
9.CHECK AMBIENT SENSOR
Press (DEF) switch one time. Temperature detected by ambient
sensor is indicated on the display.
NOTE:
If the temperature indicated on the display greatly differs from the
actual temperature, check sensor circuit first, and then check sensor.
OK or NG
OK >> GO TO 10.
NG >> Go to Ambient Sensor Circuit. Refer to ATC-86, "
Ambi-
ent Sensor Circuit".
SJIA0302E
Code No. 414243444546
Mode door position VENT B/L 1 B/L 2
FOOT
*1D/F DEF
Intake door position REC REC 20% FRE FRE FRE FRE
Air mix door position FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
Blower motor duty ratio 37% 91% 65% 65% 65% 91%
Compressor ON ON OFF OFF ON ON
Electronic control valve
(ECV) duty ratio 100% 100% 0% 0% 50% 100%
PJIA0151E
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ATC-48
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
When performing indoors, aim a light (more than 60 W) at sunload sensor, otherwise code No. 25 will indicate
despite that sunload sensor is functioning properly.
>> INSPECTION END
14.CHECK MALFUNCTIONING DOOR MOTOR POSITION SWITCH
Mode and/or intake door motor PBR(s) is/are malfunctioning.
(If two or more mode or intake door motors malfunc tion, corresponding code Nos. indicates 1 second each.)
*1: If mode door motor harness c onnector is disconnected, the following display pattern will appear.
31 →32 →33 →34 →35 →36 →Return to 31
*2: If intake door motor harness connector is disconnected, the following display pattern will appear.
37 →38 →39 →Return to 37
*3: FOOT position during automatic control. Refer to "AUXILIARY MECHANISM: FOOT POSITION SETTING
TRIMMER".
>> INSPECTION END
AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER
The trimmer compensates for differences in range of ±3 °C ( ±6 °F) between temperature setting (displayed dig-
itally) and temperature felt by customer.
Operating procedures for this trimmer are as follows:1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press (fan) UP switch to set system in auxiliary mode.
3. Display shows “61” in auxiliary mechanism. It ta kes approximately 3 seconds to enable setting operation.
SJIA1781E
Code No. *1 *2Mode or intake door position Reference page
31 VENT
Mode door motorAT C - 5 7 , "
Mode Door Motor Circuit"
32 B/L 1
33 B/L 2
34
FOOT
*3
35 D/F
36 DEF
37 FRE
Intake door motorATC-62, "
Intake Door Motor Circuit"38 20% FRE
39 REC
SJIA1782E
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TROUBLE DIAGNOSISATC-49
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4. Press temperature control switch (driver side) as desired. Temperature will change at a rate of 0.5°C
(1.0 °F) each time a switch is pressed.
CAUTION:
A decimal point is not in dicated on the display.
When battery cable is disconnected or battery voltage is below 10 V, trimmer operation is canceled. Tempera-
ture set becomes that of initial condition, i.e. 0 °C (0 °F).
AUXILIARY MECHANISM: FOOT POSITION SETTING TRIMMER
Wind distribution ratio in FOOT mode can be set.
Operating procedures for this trimmer are as follows:1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press (fan) UP switch to set system in auxiliary mode.
3. Display shows “61” in auxiliary mechanism. It ta kes approximately 3 seconds to enable setting operation.
SJIA1575E
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ATC-50
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
4. Press the mode switch as desired.
When battery cable is disconnected or battery voltage is below 10 V, trimmer operation is canceled. Wind dis-
tribution ratio set becomes that of initial condition.
AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION
When ignition switch is turned from OFF to ON, inlet port memory function at manual mode can be set.
Operating procedures for this trimmer are as follows:1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press (fan) UP switch to set system in auxiliary mode.
3. Press the intake switch as desired.
When battery cable is disconnected or battery voltage is below 10 V, memory function is canceled. Memory
function set becomes that of initial condition.
Operational CheckINFOID:0000000001328182
The purpose of the operational check is to c heck if the individual system operates properly.
CHECKING MEMORY FUNCTION
1. Press the temperature control (UP) switch (driver side) until 32°C (90 °F) is displayed.
2. Press OFF switch.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Press OFF switch.
If NG, go to trouble diagnosis procedure for ATC-85, "
Memory Function".
If OK, continue the check.
CHECKING BLOWER
SJIA1581E
LED status of
FRE position LED status of
REC position Setting status
Setting changeover
method
FRE REC
OFF OFF AUTO control AUTO control
Intake SW: ON
OFF ON AUTO control (Initial setting)
Manual REC status is memorized.
(Initial setting)
ON OFF Manual FRE status is memorized. AUTO control
ON ON Manual FRE status is memorized. Manual REC status is memorized.
Conditions : Engine running at normal operating temperature
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TERMINOLOGYGI-49
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Exhaust gas recirculation control-BPT
valve EGRC-BPT valve BPT valve
Exhaust gas recirculation control-solenoid
valve EGRC-solenoid valve EGR control solenoid valve
Exhaust gas recirculation temperature sen-
sor EGRT sensor Exhaust gas temperature sensor
EGR temperature sensor
Flash electrically erasable programmable
read only memory FEEPROM ***
Flash erasable programmable read only
memory FEPROM ***
Flexible fuel sensor FFS ***
Flexible fuel system FF system ***
Fuel pressure regulato r *** Pressure regulator
Fuel pressure regulator control solenoid
valve *** PRVR control solenoid valve
Fuel trim FT ***
Heated Oxygen sensor HO2S Exhaust gas sensor
Idle air control system IAC system Idle speed control
Idle air control valve-air regulato r IACV-air regulator Air regulator
Idle air control valve-auxiliary air control
valve IACV-AAC valve Auxiliary
air control (AAC) valve
Idle air control valve-FICD solenoid valve IACV-FICD solenoid valve FICD solenoid valve
Idle air control valve-idle up control sole-
noid valve IACV-idle up control solenoid valve Idle up control solenoid valve
Idle speed control-FI pot ISC-FI pot FI pot
Idle speed control system ISC system ***
Ignition control IC ***
Ignition control module ICM ***
Indirect fuel injection system IFI system ***
Intake air IA Air
Intake air temperature sensor IAT sensor Air temperature sensor
Knock *** Detonation
Knock sensor KS Detonation sensor
Malfunction indicator lamp MIL Check engine light
Manifold absolute pressure MAP ***
Manifold absolute pressure sensor MAPS ***
Manifold differential pressure MDP ***
Manifold differential pressure sensor MDPS ***
Manifold su rface temperature MST ***
Manifold surface temperature sensor MSTS ***
Manifold vacuum zone MVZ ***
Manifold vacuum zone sensor MVZS ***
Mass air flow sensor MAFS Air flow meter
Mixture control solenoid valve MC solenoid valve Air-fuel ratio control solenoid valve
Multiport fuel injection system MFI system Fuel injection control NEW TERM
NEW ACRONYM /
ABBREVIATION OLD TERM
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