NAVIGATION SYSTEM, Diagnostic DTC:B157D

DTC Code	DTC Name
B157D	DAB Tuner Antenna Disconnected

DESCRIPTION

This DTC is stored when a malfunction occurs in the digital audio broadcasting antenna assembly which is connected to the radio and display receiver assembly.


DTC Code	DTC Detection Condition	Trouble Area
B157D	The digital audio broadcasting antenna assembly is not connected	Amplifier antenna assembly Roof antenna pole sub-assembly No. 2 antenna cord sub-assembly Antenna cord sub-assembly Radio and display receiver assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

Note:

Check that the wire harness is properly installed and does not have any sharp bends, pinching or loose connections (Click here).

PROCEDURE

CHECK FOR DTC
1. Clear the DTCs (Click here).
2. Check for DTCs (Click here).
  
  OK
  
  No DTCs are output.
USE SIMULATION METHOD TO CHECK

(Click here)
CHECK OPTIONAL COMPONENTS
1. Check if any optional components that may decrease reception capacity, such as sunshade film or a telephone antenna, are installed.
  
  OK
  
  Optional components are installed.
  
  Note:
  Do not remove optional components without permission of the customer.
REMOVE OPTIONAL COMPONENTS AND CHECK AGAIN (SEE NOTICE ABOVE)
CHECK ROOF ANTENNA POLE SUB-ASSEMBLY
1. Check that the roof antenna pole sub-assembly is securely installed.
CHECK AND REPLACE ROOF ANTENNA POLE SUB-ASSEMBLY
CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY
1. Remove the antenna connector from the radio and display receiver assembly.
2. Turn the ignition switch to ACC with the radio and display receiver assembly connector connected.
3. Turn on the radio and turn into AM mode.
4. Place a screwdriver, thin wire or other metal object on the radio and display receiver assembly antenna jack and check that noise can be heard from the speakers.
  
  OK
  
  Noise occurs.
REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

(Click here)

CHECK NO. 2 ANTENNA CORD SUB-ASSEMBLY

Disconnect the antenna connector from the amplifier antenna assembly.
Disconnect the antenna connector from the antenna cord sub-assembly.

Measure the resistance according to the value(s) in the table below.

Standard Resistance


Tester Connection	Condition	Specified Condition
1 - 3	Always	Below 1 Ω
1-a - 3-a	Always	Below 1 Ω
1 - Body ground	Always	10 kΩ or higher
1-a - Body ground	Always	10 kΩ or higher

Table 1. Text in Illustration
*a	Front view of wire harness connector (to Amplifier Antenna Assembly)
*b	Front view of wire harness connector (to Antenna Cord Sub-assembly)

REPLACE NO. 2 ANTENNA CORD SUB-ASSEMBLY

(Click here)

CHECK ANTENNA CORD SUB-ASSEMBLY

Disconnect the antenna connector from the No. 2 antenna cord sub-assembly.
Disconnect the antenna connector from the radio and display receiver assembly.

Measure the resistance according to the value(s) in the table below.

Standard Resistance


Tester Connection	Condition	Specified Condition
3 - 1	Always	Below 1 Ω
3-a - 1-a	Always	Below 1 Ω
3 - Body ground	Always	10 kΩ or higher
3-a - Body ground	Always	10 kΩ or higher

Table 2. Text in Illustration
*a	Front view of wire harness connector (to No. 2 Antenna Cord Sub-assembly)
*b	Front view of wire harness connector (to Radio and Display Receiver Assembly)

REPLACE ANTENNA CORD SUB-ASSEMBLY

(Click here)

CHECK AMPLIFIER ANTENNA ASSEMBLY
1. Replace the amplifier antenna assembly with a known good one (Click here).
2. Clear the DTCs (Click here).
3. Check for DTCs (Click here).
  
  OK
  
  No DTCs are output.
END (AMPLIFIER ANTENNA ASSEMBLY IS DEFECTIVE)

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

(Click here)