Test L: The Navigation System Module Does Not Respond To The Diagnostic Tool

PINPOINT TEST L: THE NAVIGATION SYSTEM MODULE DOES NOT RESPOND TO THE DIAGNOSTIC TOOL

L1-L2:

L2-L3:

L4-L5:

L5-L6:

L7-L8:

L8-L9:

Normal Operation
The navigation system module communicates with the diagnostic tool through the standard corporate protocol (SCP) communications network circuits 4-EG17 (GY/BK) and 5-EG17 (BU/YE). If one of the SCP communications network become shorted to ground or voltage, or if some but not all termination resistors are lost, communications can continue. Check circuits 4-EG17 (GY/BK) and 5-EG17 (BU/YE) between the navigation system module C4209 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-EG17 (GY/BK) and 5-EG17 (BU/YE), damage to the DLC C251, damage to the navigation system module C4209, or a problem in the interior auxiliary junction box (AJB) C283b, interior AJB C283d, joint connector No. 4 C223 or joint connector No. 5 C427.

Possible Causes
- SCP data plus circuit 4-EG17 (GY/BK) open
- SCP data minus circuit 5-EG17 (BU/YE) open
- joint connector No. 4 C223
- interior AJB C283b
- interior AJB C283d
- joint connector No. 5 C427
- navigation system module C4209
- navigation system module