5
MCU Systems (Most 1981-84 vehicles)
The 6-pin MCU Test Connectors
for some vehicle models are not
equipped
terminal at position "F". This
terminal is required by the code
reader to provide a ground
signal to the vehicle's computer
to initiate the Self-Test.
If no codes are displayed during
the testing procedure, check the
Test Connector for ground
terminal at position "F". If no
terminal is present at position
"F", connect a jumper wire from
the open terminal on the Code Reader to the negative post of
the battery or a bare clean spot in the vehicle's metal frame.
If after performing all the troubleshooting procedures the
code reader still will not work consult the vehicles service
repair manual and/or contact the service department. See
page 89 for service information.
Chapter 5
CODE READER TROUBLESHOOTING GUIDE
with
a
ground
Troubleshooting
JUMP TO
GROUND
"F"
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