Test C: Navigation System Will Not Switch On

C1 - C3:

C4 - C7:

Normal Operation
Under normal operation, voltage is supplied to the navigation system module (NSM) C229a pin 1 circuit 729 (RD/WH) from the Central Junction Box (CJB) fuse 2 (5A). The ignition switch supplies power when it is in the RUN or ACCY position to the NSM C229a pin 2, circuit 1002 (BK/PK) from the CJB fuse 8 (5A). The NSM supplies voltage to the navigation system display module (NSDM) C3030a pin 1 circuit 1537 (RD). Circuits 729 (RD/WH), 1002 (BK/PK), and 1537 (RD) must be checked for voltage. If no voltage is present circuits 729 (RD/WH), 1002 (BK/PK), or 1537 (RD) are open or shorted to ground and must be checked for resistance values of less than 5 ohms. If the circuits have less than 5 ohms the CJB must be checked and repaired as necessary. Circuit 57 (BK), system ground, must be checked for a resistance value of less than 5 ohms. If more than 5 ohms is present the circuit is open. If voltage is present on all circuits and the ground is present through circuit 57 (BK), the console harness must be removed and checked pin to pin for resistance values of less than 5 ohms. If all the console harness measurements have resistance values of less than 5 ohms pin to pin, a new NSM must be installed. If after the NSM is installed the system does not switch on, a new NSDM must be installed.

Possible Causes
^ circuit 729 (RD/WH) open or shorted to ground
^ circuit 1537 (RD) open or shorted to ground
^ circuit 1002 (BK/PK) open or shorted to ground
^ circuit 57 (BK) open
^ CJB
^ navigation system console harness
^ NSM
^ NSDM