Test I: Navigation System Does Not Operate Correctly - The Audio Unit Is Inoperative

PINPOINT TEST I: NAVIGATION SYSTEM DOES NOT OPERATE CORRECTLY - THE AUDIO UNIT IS INOPERATIVE

I1-I2:

I2-I4:

I4-I6:

I7:

Normal Operation
The navigation system module communicates to the audio unit through circuits 5-GK8 (BU/YE) and 4-GK8 (GY/BK) using the controller area network (CAN) protocol. Battery voltage is supplied to the audio unit through circuit 29-MD15 (OG/BK). Circuit 10-MD15 (GY/OG) provides voltage to the audio unit with the key in the ON or ACC position. The audio unit ground is supplied through circuits 31-MD15B (BK/GN) and 31-MD15A (BK/GN).

Possible Causes
- circuit 4-GK8 (GY/BK) open, short to ground or short to voltage
- circuit 5-GK8 (BU/YE) open, short to ground or short to voltage
- circuit 31-MD15A (BK/GN) open
- circuit 31-MD15B (BK/GN) open
- navigation system module
- audio unit