Operation CHARM: Car repair manuals for everyone.
Home >> Infiniti >> 2001 >> Q45 V8-4130cc 4.1L DOHC MFI (VH41) >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P1493

P1493




SYSTEM DESCRIPTION
This system controls the vacuum signal applied to the EVAP canister purge control valve. When the ECM detects any of the following conditions, current does not flow through the EVAP canister purge control solenoid valve.
The solenoid valve cuts the vacuum signal so that the EVAP canister purge control valve remains closed.
- Start switch "ON"
- Closed throttle position
- Low or high engine coolant temperature
- During deceleration
- Engine stopped
- For 60 seconds after starting engine (After warming up to normal operating temperature)

COMPONENT DESCRIPTION




EVAP canister purge control solenoid valve
The EVAP canister purge control solenoid valve responds to signals from the ECM. When the ECM sends an OFF signal, the vacuum signal (from the intake manifold to the EVAP canister purge control valve) is cut.
When the ECM sends an ON (ground) signal, the vacuum signal passes through the EVAP canister purge control solenoid valve. The signal then reaches the EVAP canister purge control valve.




EVAP canister purge control valve
When the vacuum signal is cut by EVAP canister purge control solenoid valve, EVAP canister purge control valve shuts off the EVAP purge line.


Evaporative Emission System Diagram:






Consult-II Reference Value In Data Monitor Mode:






ECM Terminals And Reference Value:






On Board Diagnosis Logic:












DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

CAUTION: Always drive vehicle at a safe speed.

NOTE:
- If DTC P1492 is displayed with P1493, first perform "TROUBLE DIAGNOSIS FOR DTC P1492".
- If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 5 seconds before conducting the next test.

With Consult
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch "OFF" and wait at least 5 seconds.
3. Turn ignition switch "ON".
4. Select "PURG CN/V & S/V P1493" of "EVAPORATIVE SYSTEM" in "DTC WORK SUPPORT" mode with CONSULT-II.
5. Touch "START".
6. Start engine (TCS switch "OFF") and let it idle for at least 90 seconds.
7. When the following conditions are met, "TESTING" will be displayed on the CONSULT-II screen. Maintain the conditions continuously until "TESTING" changes to "COMPLETED". (It will take approximately 30 seconds.)

Vehicle speed: 36 - 120 km/h (22 - 75 MPH)
CMPS-RPM (POS): 900 - 6,300 rpm B/FUEL SCHDL: 2 - 4.8 msec
Selector lever: Suitable position
If "TESTING" is not displayed after 5 minutes, retry from step 2.

8. Make sure that "OK" is displayed after touching "SELF DIAG RESULTS". If "NG" is displayed, refer to "DIAGNOSTIC PROCEDURE".

OR




With Generic Scan Tool
1. Start engine (TCS switch "OFF") and warm it up to normal operating temperature.
2. Select "MODE 1" with GST.
3. Check coolant temperature.

Coolant temperature: 30 - 100 °C (86 - 212 °F)
Be sure that water temperature does not exceed 100 °C.
If it becomes higher than 100 °C, cool down the engine and perform the procedure again from the beginning.

4. Turn ignition switch "OFF" and wait at least 5 seconds.
5. Turn ignition switch "ON" and wait at least 15 seconds.
6. Restart engine and let it idle for at least 90 seconds.
7. Maintain the following conditions for at least 30 seconds.

Vehicle speed: 36 - 120 km/h (22 - 75 MPH)
Engine speed: 900 - 6,300 rpm
Gear position: Suitable gear position
Coolant temperature: 30 - 100 °C (86 - 212 °F)

8. Select "MODE 7" with GST.
9. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".

NOTE:
- Hold the accelerator pedal as steady as possible during driving in steps 7.
- If the driving conditions are not satisfied in steps 7, restart the procedure.
- It is better that the fuel level is low.

OR




Without Scan Tools
1. Start engine (TCS switch "OFF") and warm it up to normal operating temperature.
2. Check voltage between ECM terminal (67) and ground

Voltage: 3.12 - 0.8 V
Perform the following procedure before the voltage drops below 0.8 V. If the voltage drops below 0.8 V, cool down the engine and perform the entire procedure all over again.

3. Turn ignition switch "OFF" and wait at least 5 seconds.
4. Turn ignition switch "ON" and wait at least 15 seconds.
5. Restart engine and let it idle for at least 90 seconds.
6. Maintain the following conditions for at least 30 seconds.

Vehicle speed: 40 - 120 km/h (25 - 75 MPH)
Engine speed: 1,000 - 2,100 rpm
Gear position: Suitable gear position
Check voltage between ECM terminal (67) and ground: 3.12- 0.8 V

7. Stop the vehicle, turn ignition switch "OFF", wait at least 5 seconds, and then turn "ON".
8. Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.
9. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".

NOTE:
- Hold the accelerator pedal as steady as possible during driving in steps 6.
- If the driving conditions are not satisfied in steps 6, restart the procedure.
- It is better that the fuel level is low.

Part 1:




Part 2:




DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION

EVAP canister purge control solenoid valve










With Consult
1. Turn ignition switch "ON".
2. Select "PURG CONT S/V" of "ACTIVE TEST" mode with CONSULT-II.
3. Start engine and warm it up to normal operating temperature.
4. Disconnect vacuum hose at EVAP canister purge control valve.
5. Touch "ON" and "OFF" and check for vacuum passing through the hose.

OR







Without Consult
Check air passage continuity.
If NG or operation takes more than 1 second, replace solenoid valve.




EVAP canister purge control valve
Check EVAP canister purge control valve as follows:

1. Blow air in port (A) and (C), then ensure that there is no leakage.
2. Blow air in port (B), then ensure that there is a resistance to flow out of port (C).
3. Apply vacuum to port (A). [Approximately -13.3 to -20.0 kPa (-100 to -150 mmHg, -3.94 to -5.91 inHg)]
Blow air in port (C) and ensure free flow out of port (B).

EVAP canister vent control valve
Check air passage continuity.







With Consult
Perform "VENT CONTROL/V" in "ACTIVE TEST" mode with CONSULT-II

OR







Without Consult
If NG or operation takes more than 1 second, clean valve using air blower or replace as necessary.

If the portion (B) is rusted, replace EVAP canister vent control valve.

Make sure new O-ring is installed properly.




Water separator
1. Check visually for insect's nest in the water separator air inlet.
2. Check visually for cracks or flaws in the appearance.
3. Check visually for cracks or flaws in the hose.
4. Check that (A) and (C) are not clogged by blowing air into (B) with (A), and then (C) plugged.
5. In case of NG in items 2 - 4, replace the parts.

NOTE: Do not disassemble water separator.
pro multis · About Operation CHARM