There are self-diagnositic connectors on all models, when connected with the key ON (engine off), flash trouble codes on the LED light of the oxygen moniter of the ECU. View Full Image The connectors are under the steering wheel, to the left of the module on most models.On carberated and SPFI injected 89 models,the test connectors are located on the engine side/driver's side of the firewall.Imprenza models have the ECU and test connectors located behind the right side of the dash, instead of the left.On SVX models the connectors are located behind the driver's side kick panel. Test Modes
There are self-diagnositic connectors on all models, when connected with the key ON (engine off), flash trouble codes on the LED light of the oxygen moniter of the ECU.
The codes are displayed as pulses of the LED mounted on the module. Long pulses (1.2 seconds) indicate tens and the short pulses (.2 seconds) indicate ones. Pulses are seperated by .3 second puses and codes are seperated by 1.8 second pauses. NOTE:on 89 MPFI models, the Oxygen Moniter light and ECU are mounted under the rear package shelf and are only accessible from the trunk. On some later models the Check engine lamp and O2 monitor lamp flash the code(s) corresponding to the faulty part. The long segment (1.2 sec on) indicates a "ten", and the short segment (0.2 sec on) signifies a "one".
Codes will only clear when the faulty system or circuit has been repaired. After making the repairs, codes can be cleared by connecting 2 pairs of connectors, the "Self-diagnostic" connectors and the "Read Memory" connectors that are usually to the right of the diagnostic connectors.
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