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Test R: The Electronic Parking Brake Module Does Not Respond To The Diagnostic Tool

PINPOINT TEST R: THE ELECTRONIC PARKING BRAKE MODULE DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


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Normal Operation
The electronic parking brake module communicates with the diagnostic tool through the standard corporate protocol (SCP) communications network circuits 4-CG16 (GY/RD) and 5-CG16 (BU/RD). If one of the SCP communications network circuits become shorted to ground or voltage, or if some but not all termination resistors are lost, communications can continue. Check circuits 4-CG16 (GY/RD) and 5-CG16 (BU/RD) between the electronic parking brake module C4205b and the data link connector (DLC) C251. The 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-CG16 (GY/RD) and 5-CG16 (BU/RD), damage to the DLC C251, damage to the electronic parking brake module C4205b, or a problem in the interior auxiliary junction box (AJB) C283b, interior AJB C283d, joint connector No. 5 C427 or joint connector No. 4 C223.

Possible Causes
- SCP data plus circuit 4-CG16 (GY/RD) open
- SCP data minus circuit 5-CG16 (BU/RD) open
- joint connector No. 4 C223
- DLC C251
- interior AJB C283b
- interior AJB C283d
- joint connector No. 5 C427
- electronic parking brake module C4205b
- electronic parking brake module