Diagnosis & Repair Procedure
WARNING: This page is about a different car, the 2002 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.
- Perform DTC confirmation procedure. See DTC CONFIRMATION PROCEDURE under SELF-DIAGNOSTIC SYSTEM. Check for DTCs during KOER or KOEO self-test. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. If DTC P0511 is present, go to next step. If DTC P0511 is not present, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
- Turn ignition off. Disconnect IAC valve connector. Check for loose, damaged or corroded connector terminals. Repair as necessary, and go to step 8 . If connector terminals are okay, go to next step.
- Check IAC valve operation. See SYSTEM & COMPONENT TESTING - MIATA, MILLENIA, MPV, PROTEGE, PROTEGE5 & 626 article. Replace IAC valve as necessary and go to step 8 . If IAC valve is okay, go to next step.
- Disconnect PCM connector. Check for loose, damaged or corroded connector terminals. Repair as necessary, and go to step 8 . If connector terminals are okay, go to next step.
- Reconnect PCM connector. Turn ignition on. Measure voltage between ground and IAC valve harness connector terminal "B" (Green/Red wire). If battery voltage is present, go to next step. If battery voltage is not present, repair open in Green/Red wire between IAC valve and PCM. See WIRING DIAGRAMS article. Repair as necessary and go to step 8 .
- Turn ignition on. Measure voltage between ground and IAC valve harness connector terminal "B" (Blue/Orange wire). If battery voltage is present, go to next step. If battery voltage is not present, repair open in Blue/Orange wire between IAC valve and PCM. See WIRING DIAGRAMS article. Repair as necessary and go to step 8 .
- Disconnect PCM connector. Check for continuity between ground and PCM harness connector terminal No. 83 (Green/Red wire). See Figure . If continuity is not present, go to next step. If continuity is present, repair short to ground in Green/Red wire between IAC valve and PCM. See WIRING DIAGRAMS article. Repair as necessary and go to next step.
- Reconnect all connections. Turn ignition on. Clear DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. Perform DTC confirmation procedure. See DTC CONFIRMATION PROCEDURE under SELF-DIAGNOSTIC SYSTEM. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. If DTC P0511 is present, replace PCM and go to next step. See REMOVAL, OVERHAUL & INSTALLATION article. On vehicles equipped with immobilizer system, reprogram ignition key identification numbers. See COMPUTER RELEARN PROCEDURES - IMPORT article in GENERAL INFORMATION. If DTC P0511 is not present, go to next step.
- Perform DTC confirmation procedure. See DTC CONFIRMATION PROCEDURE under SELF-DIAGNOSTIC SYSTEM. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. If any other DTC is present, go to appropriate test.