Engine Controls - PCM Snapshot Anomaly

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Bulletin No. T-92-100
File in Group 6E
Number 100
Corp. Ref. No. 216004
Date May, 1992


SUBJECT: PCM SNAPSHOT ANOMALY


MODELS AFFECTED: 1993 ALLANTES


Some 1993 Allantes may not properly display PCM code snap data due to software anomaly in the diagnostic snapshot code display sequence. The following sequence of events must occur:

1. After entering diagnostics, all stored codes must be allowed to display.

2. Select H1 when "PCM?" is displayed.

3. Select HI when "PCM SNAPSHOT" is displayed.

At this point "P000 SNAPSHOT?" may be displayed and other PCM code snapshots may not appear after "PCM SNAPSHOT?" is selected. Although this is not a correct display, it does not affect the accuracy of the on-board diagnostics.

To enable display of all PCM code snapshots and prevent "P000 SNAPSHOT?" from being displayed, terminate the display of all stored codes after entering diagnostics by pressing LO.

IMPORTANT: DO NOT attempt to repair this condition. Replacement of the BCM, PCM, EPROM's, or EEPROM's will not correct this condition.