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Can you check for codes again? and check for pending codes also, there should be something stored.
Are there any aftermarket accesories on the truck?
How old is the battery?
I need to log off for to get lunch. Will be back
That is too bad, that would have been the easy fix!!
This diagnostic will need to be done to determine the problem.
Attachments are only available to registered users.
SYMPTOM P1618-PRIMARY 5-volt SUPPLY ERRATICWHEN MONITORED Ignition on.SET CONDITION When the PCM recognizes the Primary 5-volt Supply circuit voltage is varying too much to quickly. One Trip Fault. ETC light is flashing.POSSIBLE CAUSES - Good trip equal to zero - (F855) Primary 5-volt supply shorted to ground - Sensor shorted to ground - Internal sensor - (F855) Primary 5-volt supply shorted to voltage - (F855) Primary 5-volt supply circuit open - PCM