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Code 14, Idle Control System EACV

  1. Turn off ignition. Remove clock fuse in the under-hood relay box for 10 seconds to reset ECU. Start engine and observe PGM-FI warning light. If light is off, problem is intermittent. Test drive and check again.
  2. If light is on, turn ignition off. Disconnect Electronic Air Control Valve (EACV) connector. Check resistance between the 2 connector terminals on valve.
  3. Resistance should be 8-15 ohms. If not within specification, replace EACV. If resistance is within specification, proceed to next step.
  4. Check for continuity to ground on each EACV connector terminal. If continuity exists, replace EACV. If no continuity exists, turn ignition on. On Prelude models, connect voltmeter between Black/Yellow (pos.) and Blue/Red (neg.) terminals.
  5. Check for battery voltage. If no battery voltage exists, proceed to step 6). If battery voltage exists, disconnect connector from ECU and again check for battery voltage. If battery voltage still does not exist, substitute a known good ECU. If condition is rectified, replace original ECU. If battery voltage does exist, repair short in Blue/Red wire between ECU terminal A11 and EACV.
  6. If no battery voltage existed in step 5), measure voltage between ground and Black/Yellow wire terminal. If battery voltage now exists, proceed to step 7). If battery voltage still does not exists, repair open Black/Yellow wire between fuse No. 12 and EACV.
  7. If battery voltage exists, turn ignition off. Reconnect EACV connector. Connect system checker harness "A" connector to main wire harness only, not ECU. Turn ignition on. Using a voltmeter, measure voltage between connector terminals A11 (pos.) and A18 (neg.). If voltage does not exist, repair open in wire between ECU terminal A11 and EACV.
  8. If battery voltage exists, connect and disconnect terminal A11 to A18. If EACV does not click when connector is connected and disconnected, replace EACV. If EAVC clicks, substitute a known good ECU. If condition is rectified, replace original ECU.
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