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Test G

PINPOINT TEST G: THE DUAL AUTOMATIC TEMPERATURE CONTROL (DATC) MODULE DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


Test G1-G2:






Normal Operation
The DATC module 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 circuits 914 (TN/OG) and 915 (PK/LB) between the DATC module C228a and the DLC C251. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open in the SCP network circuits, damage to the DLC C251, the DATC module C228a, or a problem in the in-line connectors.

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