With Manufacturer's Scantool

If a problem is sensed by the logic module or SMEC, often enough to be considered a malfunction, a fault code is stored in the module memory. If the problem is repaired, or ceases to occur, the module will cancel the fault code after 20-40 vehicle key On/Off cycles on 1984-87 models or 50-100 vehicle key On/Off cycles on 1988 models. Fault codes that remain in the module memory can be called up and displayed either by using diagnostic tool C-4805 or by observing flashes or the power loss lamp. Fault codes can be obtained using the following procedures:

Using Tester C-4805

1. Connect tester to diagnostic connector located in engine compartment near passenger side strut tower.
2. Start engine, if possible, move transmission selector through range and cycle A/C compressor on and off, then stop engine.
3. Turn ignition switch on, off, on, off and on within 5 seconds.
4. Power loss/check engine lamp should light for 3 seconds, then go out and stored fault codes will be displayed on tool. After obtaining fault codes using tester C-4805, test circuits as outlined in ``Switch Tests'' and ``Actuation Test Mode (ATM) Tests.''