Engine Mount Control System: Odyssey
CAUTION:
When substituting a known-good PCM, immobilizer code must be rewritten to replacement PCM using Honda PGM tester, or engine will not start.
NOTE:
Following procedure should be performed if engine vibrates excessively at idle.
- Check vacuum lines and hoses for damage and proper connection. Repair/replace hoses as necessary. If vacuum lines and hoses are okay, start and warm engine to normal operating temperature (radiator cooling fan comes on). Allow engine to idle. If idle RPM is less than 730 RPM, go to next step. If idle RPM is not less than 730 RPM, adjust idle speed. See ON-VEHICLE ADJUSTMENTS article.
- Fully depress brake pedal. With transaxle in gear, have an assistant disconnect and reconnect engine mount control solenoid valve 2-pin connector. See Fig 1 . If there is no noticeable change in idle RPM when engine mount control solenoid valve 2-pin connector is disconnected, go to next step. If there is a noticeable change in idle RPM when engine mount control solenoid valve 2-pin connector is disconnected, engine mount control system is operating properly. Reconnect engine mount control solenoid valve 2-pin connector.
- Place transaxle in Neutral or Park. Disconnect engine mount control solenoid valve 2-pin connector. Measure voltage of Black/Yellow wire between body ground and engine mount control solenoid valve 2-pin connector terminal No. 2. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/Yellow wire between engine mount control solenoid valve 2-pin connector and No. 6 (15-amp) fuse in driver's underdash fuse/relay box. See WIRING DIAGRAMS article.
- Measure voltage across both terminals (Black/Yellow wire and Green/White wire) of engine mount control solenoid valve 2-pin connector. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Green/White wire between engine mount control solenoid valve and PCM connectors. See WIRING DIAGRAMS article. If Green/White wire is okay, substitute known-good PCM and retest. If battery voltage is now present, replace original PCM.
- Increase engine speed above 1000 RPM and measure voltage across both terminals (Black/Yellow wire and Green/White wire) of engine mount control solenoid valve 2-pin connector. If battery voltage is not present, go to next step. If battery voltage is present, repair short to ground in Green/White wire between engine mount control solenoid valve and PCM connectors. See WIRING DIAGRAMS article. If Green/White wire is okay, substitute known-good PCM and retest.
- Disconnect upper vacuum hose from engine mount control solenoid valve, and connect vacuum pump/gauge to hose. Apply vacuum to hose for 20 seconds. If engine mount holds vacuum, go to next step. If engine mount does not hold vacuum, repair or replace vacuum hose or engine mount.
- Release vacuum from engine mount, and then apply vacuum again. If there is a noticeable change in idle RPM smoothness with or without vacuum applied, go to next step. If there is no noticeable change in idle RPM smoothness with or without vacuum applied, replace engine mount.
- Remove vacuum pump/gauge from upper vacuum hose. Connect vacuum pump/gauge to upper port of engine mount control solenoid valve. Observe vacuum gauge reading with engine at idle and at a speed above 1000 RPM. If manifold vacuum is present at idle and decreases when engine speed is above 1000 RPM, engine mount control system is okay at this time. Check engine mount and vacuum hoses, if necessary. If manifold vacuum is not present at idle and does not decrease when engine speed is above 1000 RPM, replace engine mount control solenoid valve.