Actron GM Code Scanner CP9001 - Manual (Page 14)

14
called “Computerized Engine
Controls”, “Electronic Engine
Controls” or “Tune-Up Information.”
• Follow all the steps in the diagnostic
procedure for the trouble code.
• Be sure to erase the trouble codes
from computer memory after
completing repair work. (See Step 5,
“Erasing Codes from Computer
Memory”.)
• Drive vehicle for at least 10 minutes
at normal temperature, cruise speed
and load.
– Read codes again to verify trouble
code is gone (problem fixed). Other
codes may have been repaired at
the same time!
Dealing with “Intermittent” Codes
These codes are for problems which
happened in the past, but are not
present now.
• Usually these problems are due to
loose connections or bad wiring.
The problem cause can often be
found with a thorough visual and
“hands-on” inspection. (Refer to
Step 1, “Visual Inspection”.)
• Refer to the vehicle service manual
diagnostic code section. You can not
use the code chart procedures
because they are for “hard”
problems - those which are present
now. However, the charts have
suggestions for dealing with
intermittents and can tell you where
bad connections, etc., might exist.
You can also refer to the “Diagnosis
by Symptom” charts.
• Be sure to erase the trouble codes
from computer memory after
completing repair work. (See Step 5,
“Erasing Codes from Computer
Memory”.)
• Drive vehicle for at least 10 minutes
at normal temperature, cruise speed
and load.
– Read codes again to verify trouble
code is gone (problem fixed).
Other codes may have been
repaired at the same time!
Dealing with No Trouble Codes
Have a driveability problem, but only
get code 12? Make sure you do Step
1, “Visual Inspection” and Step 2,
“Basic Mechanical Checks”. If you did
not find the problem, then refer to
“Diagnosis by Symptom” charts in
vehicle service manual.
5) Erasing Codes from Computer
Memory
Erase codes from memory whenever
you complete a repair or to see if a
problem will occur again. Note: The
computer will automatically erase
codes after several restarts (typically
50) if the problem does not return.
GM
Proceed as follows:
• Observe all safety precautions. (See
page 2.)
• Turn ignition key ON.
• Insert Code
Scanner.
Make sure
TEST switch
is in ENGINE
position!
• Turn ignition key
OFF.
• Remove the
ECM fuse
from the
fuse block
for 10
seconds.
• Replace
fuse.
• Remove
Code Scanner.
If ECM fuse cannot be located, then –
• Disconnect power to the computer.
To do this:
–Disconnect
the positive
battery
terminal
“pigtail”,
OR
T E S T
ABS ENGINE
TM
GM 1982 & higher - CP 9001
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