Data Link Connector Diagnosis

Data Link Connector Diagnosis

Refer to Engine Controls Schematics DLC, PCM Power and Ground .

Circuit Description

Important: Use a properly functioning scan tool with the diagnostic tables in this section. DO NOT use the Clear Info function unless instructed by a diagnostic procedure.


Important: This vehicle, equipped with a powertrain control module (PCM), utilizes an electrically erasable programmable read only memory (EEPROM). Program the new PCM when the diagnostics call for replacement of the PCM. Refer to Powertrain Control Module Replacement Service and Repair.


Test Description

The numbers below refer to the step numbers on the diagnostic table.
6. This step will determine if any of the other components/modules connected to the serial data circuit are causing a no engine data condition.
7. This step will determine if more than one symptom is present.
8. This step will determine if the serial data circuit is shorted to ground.
9. This step will determine if battery positive voltage is being supplied to the DLC.
10. This step will check the DLC grounds.
11. A voltage reading of less than 0.50 volt is considered as 0 volts.
12. A voltage reading of more than 10 volts is considered to be B+.
16. The engine will run but the PCM will not communicate through the serial data circuit if ignition positive voltage is not supplied to this circuit.
19. This will determine if voltage is being supplied to the fuse.