Test D17 - Re-Initialization

NOTE: Perform this CIRCUIT TEST when Codes 71, 72 or 78 is displayed or when directed by other test procedures.

NOTE: The electrical signatures of some aftermarket components may affect driveability of the vehicle.

Fig 1: EEC Power Relay Circuit

Codes 71, 72 or 78: Checking For Electrical Noise Sources. Continuous Memory Code 72 or 78 indicates that power to the ECA was interrupted sometime during the last 40 warm-up cycle. A Continuous Code 71 indicates that sometime during the past 40 warm-up cycles, the ECA software requested a re-initialization or review of previous drive sequence data. This process could result in a driveability complaint. Possible causes for this fault or complaint are:
- Vehicle power interrupted to ECA.
- Spark plug wires incorrectly routed too close to ignition.
- High tension wire shielding removed.
- Electrical, radio, or motor static noise.
- Test pin No. 20 (case ground) not grounded to chassis.
- Open diodes on A/C or ISC relay.
Turn key off. Ensure that EEC wiring and components are more than 2" (50 mm) away from secondary ignition wires. Make sure that EEC wiring and components are more than 4" (100 mm) away from distributor, ignition coil, and starter motor and its wiring. If these items are correct, go to next step. If not, correct as necessary and repeat QUICK TEST.
Checking Harness and Case Ground. Turn key off. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 20 and chassis ground. If reading is less than 5 ohms, go to next step. If not, repair wiring harness and repeat QUICK TEST.
Case Ground Check With Harness Disconnected. Turn key off. Connect ECA to breakout box, but disconnect harness from breakout box. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 20 and ECA metal case. If reading is less than 5 ohms, go to next step. If reading is more than 5 ohms, replace ECA and repeat QUICK TEST.
"WIGGLE" Testing VPWR Circuit. With KOEO, connect DVOM to SELF TEST connector. Deactivate SELF-TEST. Using Continuous Monitor Mode, perform "WIGGLE" test on EEC-IV harness from ECA to power relay. If a fault is indicated or a Code 71 is displayed, repair intermittent in VPWR circuit. If no fault is indicated, inspect harness connections and pins. Replace power relay and rerun QUICK TEST.
Code 19: Internal Voltage. Code 19 indicates the ECA voltage regulator does not have the ability to maintain correct internal voltage. Run KOEO SELF-TEST, if Code 19-10-11 is present, replace ECA and rerun test. If Code 19-10-11 is not present, service other codes as indicated.