Test D

PINPOINT TEST D: THE INSTRUMENT CLUSTER DOES NOT RESPOND TO THE DIAGNOSTIC TOOL

Test D1-D2:

Normal Operation
The instrument cluster 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 instrument cluster C220a 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 an open in the SCP circuits, damage to the DLC C251, damage to the instrument cluster C220a, 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
- instrument cluster