DTC 0704

Evaporative Emission (EVAP) Control System Pressure Sensor
The EVAP control system pressure sensor detects pressure in the purge line. The sensor output voltage to the ECM increases as pressure increases. The EVAP control system pressure sensor is not used to control the engine system. It is used only for on-board diagnosis.




CONSULT REFERENCE VALUE IN DATA MONITOR MODE




ECM TERMINALS AND REFERENCE VALUE
Specification data are reference values and are measured between each terminal and (43) (ECCS ground).




ON BOARD DIAGNOSIS LOGIC

DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE
With Consult
(1) Start engine and warm it up sufficiently.
(2) Check that tank fuel temperature is above 0°C (32°F).
(3) Turn ignition switch "OFF" and wait at least 5 seconds.
(4) Turn ignition switch "ON".
(5) Select "DATA MONITOR" mode with CONSULT.
(6) CONSULT least 3 seconds.

OR

With GST
(1) Start engine and warm it up sufficiently.
(2) Check that voltage between ECM terminal (63) and ground is less than 4.2V.
(3) Turn ignition switch "OFF" and wait at least 5 seconds.
(4) Turn ignition switch "ON" and wait at least 3 seconds.
(5) Select "MODE 3" with GST.

OR

No Tools
(1) Start engine and warm it up sufficiently.
(2) Check that voltage between ECM terminal (63) and ground is less than 4.2V.
(3) Turn ignition switch "OFF" and wait at least 5 seconds.
(4) Turn ignition switch "ON" and wait at least 3 seconds.
(5) Turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
(6) Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.







DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION
EVAP Control System Pressure Sensor
1. Remove EVAP control system pressure sensor with its harness connector connected.
2. Remove hose from EVAP control system pressure sensor.




3. Use pump to apply vacuum and pressure to EVAP control system pressure sensor as shown in figure.
4. Check output voltage between terminal (2) and engine ground.

Pressure (Relative to atmospheric pressure) / Voltage (V)
0 kPa (0 mmHg, 0 inHg) / 3.0 - 3.6
-9.3 kPa (-70 mmHg, -2.76 inHg) / 0.4 - 0.6

CAUTION: Always calibrate the vacuum pump gauge when using it.

5. If NG, replace EVAP control system pressure sensor.