Functional Test
- Disconnect upper vacuum hose of solenoid valve from idle boost throttle controller and connect a vacuum gauge. See Fig 1
. Start engine. If vacuum is present, go to next step. If vacuum is not present, go to step 3).
- Disconnect 2-pin connector near solenoid valve. If vacuum is still present, replace solenoid valve. If vacuum is not present, A/C signal to ECU should be inspected and corrected. See A/C SWITCH SIGNAL
under ENGINE SENSORS & SWITCHES in this article.
- Turn A/C switch on. Vacuum should now be present. If not, go to next step. If vacuum is present, both A/C idle boost solenoid valve and A/C signal are okay.
- Disconnect 2-pin connector near solenoid valve. Measure voltage between Red (positive) wire terminal and Black (negative) wire terminal on harness. See Fig 1
. If battery voltage is not present, go to next step. If battery voltage is present, disconnect lower vacuum hose from solenoid valve and connect a vacuum gauge to the disconnected hose. If manifold vacuum is not present, check routing of lower hose to solenoid valve. If manifold vacuum is present, replace solenoid valve.
- Measure voltage between Red (positive) wire terminal and ground. If battery voltage is now present, repair open or short in Black (negative) wire between solenoid valve and ground. If battery voltage is still not present, voltage from ECU should be inspected and corrected. See TESTS W/CODES - 2.0L PGM-CARBURETED
article.
Courtesy of AMERICAN HONDA MOTOR CO., INC.