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Home >> Mercury >> 2004 >> Monterey V6-3.9L VIN 6 >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Information Bus >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Tests >> Test C
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Test C

PINPOINT TEST C: THE POWERTRAIN CONTROL MODULE (PCM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


Test C1:






Test C1-C2:






Normal Operation
The PCM communicates with the diagnostic tool through the SCP communications network circuits 914 (TN/OG) and 915 (PK/LB). If one of the bus wires becomes shorted to ground or voltage, or if some but not all termination resistors are lost, communications can continue at a degraded level. Check SCP circuits 914 (TN/OG) and 915 (PK/LB) between the PCM C175 and the data link connector (DLC) C251. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is either an open in the SCP network circuits, damage to the DLC C251, damage to the PCM C175, or a problem in the in-line connector.

Possible Causes
- SCP circuits 914 (TN/OG) and 915 (PK/LB), shorted to ground or open
- DLC C251
- PCM
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