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Test P

PINPOINT TEST P: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 NETWORK COMMUNICATION


Test P1-P4:






Test P4-P6:






Normal Operation
The RCM communicates with the diagnostic tool through the ISO 9141 communications network circuit 4-EE1 (GY/RD). If circuit 4-EE1 (GY/RD) becomes open or shorted to ground, communications to that module will not be possible. Check circuit 4-EE1 (GY/RD) between the RCM C310a and the 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 circuit 4-EE1 (GY/RD), damage to the DLC C251, in-line C212 or damage to the C310a.

Possible Causes
- circuit 4-EE1 (GY/RD) shorted to ground or open
- in-line C212
- RCM C310a
- DLC C251
- RCM
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