DTC P1459 - EVAP Control
- Start engine. Raise and hold engine speed at 3000 RPM with transmission in Park or Neutral, until radiator cooling fan comes on. Perform PCM reset procedure. See PCM RESET PROCEDURE/CLEARING CODES . Connect SCS service connector. Let engine idle. If DTC P1459 is not indicated, system is operating properly at this time. Problem is intermittent. Check for poor connections or loose wires at EVAP purge flow switch, control box and PCM connectors. See WIRING DIAGRAMS section.
- If DTC P1459 is indicated, turn ignition off. Check EVAP system vacuum hoses for proper routing, leaks or restrictions. Repair vacuum hoses as necessary. If vacuum hoses are okay, disconnect 2-pin purge flow switch. Check for continuity between PCM terminals A10 and C10. See Figure . If continuity does not exist, replace EVAP purge flow switch.
- If continuity exists, disconnect PCM connector "C". Check for continuity between EVAP purge flow switch harness connector terminals (Brown and Black wires). On all models, if there is continuity, repair Brown wire for a short between PCM and EVAP purge flow switch. If continuity does not exist, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.