Diagnostic Aids

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

• SPOUT wiring harness circuit.
• Base timing.
• Faulty ECA.

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

• Basic engine condition (valves, vacuum leaks, valve timing, etc.).
• Distributor.
• TFI module.

Fig 1: TFI Spark Timing Check Circuit

1) Check For Power To ECA  Turn ignition off. Disconnect 60-pin ECA connector. Inspect terminals, and repair if damaged. Install EEC-IV Breakout Box (T83L-50-EEC-IV), leaving ECA 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 voltage reading is less than 10.5 volts, go to CIRCUIT TEST X (Continental, Sable, Taurus, Tempo and Topaz) or CIRCUIT TEST B (all others). If both voltage readings are 10.5 volts or more, go to step 2).

2) Check SPOUT Circuit For Continuity  Turn ignition off. Disconnect TFI module. Measure resistance between test pin No. 36 at breakout box and SPOUT terminal at TFI module wiring harness connector. If resistance is more than 5 ohms, repair open circuit. Reconnect all components, and check ignition timing. If resistance is 5 ohms or less, go to step 3).

3) Check SPOUT Voltage At ECA  Turn ignition off. Connect ECA to breakout box. Reconnect TFI module. Ensure timing switch on breakout box is in DIST position. Set DVOM on 20-volt AC scale. Start engine. Measure voltage between test pin No. 36 and negative battery terminal. If voltage is 4-10 volts AC, EEC-IV system is okay. Check ignition system. See IGNITION SYSTEMS in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section. If voltage is not 4-10 volts, replace ECA and repeat QUICK TEST  .