Diagnostic Aids

WARNING: This page is about a different car, the 1995 Mazda MX-6 and 1995 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.

Perform this test when checking computed timing or if directed by QUICK TEST. This test is intended to diagnose:

Wiring harness circuit (SPOUT).
Base timing.
Powertrain Control Module (PCM).

To prevent replacing good components, be aware the following non-EEC related areas may be at fault:

Basic engine condition (compression, valve timing, etc.).
Distributor.
Ignition Control Module (ICM).

1) KOER Code 213: Check For Power To PCM Turn ignition off. Disconnect PCM 60-pin connector and inspect for damaged pins, corrosion and loose wires. Repair as necessary. Install Breakout Box (49-UN01-058), leaving PCM disconnected. Turn ignition on. Measure voltage between test pins No. 37 and 40 and between test pins No. 57 and 60 at breakout box. If either reading is 10.5 volts or less volts, go to TEST B. If both voltage readings are more than 10.5 volts, go to next step.

2) Check SPOUT Circuit Continuity Turn ignition off. Disconnect ICM. With breakout box installed and PCM disconnected, measure resistance between test pin No. 36 at breakout box and SPOUT terminal at ICM wiring harness connector. If resistance is 5 ohms or more, repair open circuit. Remove breakout box, reconnect all components and check ignition timing. If resistance is less than 5 ohms, go to next step.

3) Check SPOUT Circuit For Short To B+ (Excluding VREF) Turn ignition off. Disconnect ICM. Turn ignition on. With breakout box installed and PCM disconnected, measure voltage between test pin No. 36 and test pins No 40 or 60 at breakout box. If voltage is more than 10.5 volts, repair short circuit. Remove breakout box, reconnect all components and repeat QUICK TEST. If voltage is 10.5 volts or less, go to next step.

4) Check SPOUT Circuit For Short To PIP, VREF & Ground Turn ignition off. Disconnect ICM. With breakout box installed and PCM disconnected, to check for shorts to VREF, use DVOM to measure resistance between test pins No. 26 and 36 at breakout box. To check for shorts to PIP, measure resistance between test pins No. 36 and 56 at breakout box. To check for shorts to ground, measure resistance between test pin No. 36 and test pins 16, 20, 40, 46 and 60 at breakout box. If any reading is 10,000 ohms or less, repair short circuit. Remove breakout box, reconnect all components and repeat QUICK TEST. If all readings are more than 10,000 ohms, EEC-IV system is okay. Check and repair ignition system as necessary. See IGNITION SYSTEM in SYSTEM/COMPONENT TESTS - 2.0L article.