6000 V6-173 2.8L (1988)
group of four called "quad-drivers." Failure of one driver can damage any other driver in the set.
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A shorted solenoid, relay coil, or harness in a GMP4 computer will not damage the ECM but will cause the component to be inoperative.
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J 34636 or BT 8405 testers or equivalent provide a fast, accurate means of checking for a shorted coil or a short to battery voltage.
Mem-Cal may be faulty.
Although these rarely fail, it operates as part of the ECM. Therefore, it could be the cause of the problem. Substitute a known good Mem-Cal.
Replacement ECM may be faulty.
After the ECM is replaced, the system should be rechecked for proper operation. If the diagnostic chart again indicates the ECM is the
problem, substitute a known good ECM. Although this is a rare condition, it could happen.
