GM Historic (OBD I) Diagnostics
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5
Manual Erase Methods
Alternate Method 1:
1) Turn ignition key off.
2) Locate fuse box and remove ECM fuse.
3) Wait 20 seconds.
4) Replace the fuse.
Alternate Method 2:
1) Turn ignition key off.
2) Remove power from Scan Tool.
3) Disconnect Scan Tool from vehicle.
4) Disconnect negative (-) battery cable. Wait 30 seconds, then replace
the cable.
✓The computer has a learning ability to compensate for minor
variations in engine operation. Whenever power is removed from
the PCM, the computer must relearn various functions. Vehicle
performance may be noticeably different until this is
accomplished. This is a temporary situation and is normal. The
learning process takes place during warm engine driving.
Special Tests Menu
All items marked with “-” are covered either in section 3 or 4.
These items are not covered in this section.
❒Special Tests Menu
❒Field Service
– Review Data
–Print Data
–Tool Setup
IMPORTANT