DTC Troubleshooting: B18C7, B1E77

DTC B18C7: Open in the Left Side BSI Radar Unit Indicator Circuit
DTC B1E77: Open in the Right Side BSI Radar Unit Indicator Circuit

NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description	DTC
B18C7 Open in the left side BSI radar unit indicator circuit
B1E77 Open in the right side BSI radar unit indicator circuit

Problem verification:

Problem verification

?1.	Turn the vehicle to the ON mode.

?2.	Clear the DTC with the HDS.

?3.	Turn the vehicle to the OFF (LOCK) mode.

?4.	Turn the vehicle to the ON mode, then wait for at least 2 seconds.

?5.

Check for DTCs with the HDS.

DTC Description	DTC
B18C7 Open in the left side BSI radar unit indicator circuit
B1E77 Open in the right side BSI radar unit indicator circuit

Is DTC B18C7 or B1E77 indicated?


	YES

The failure is duplicated. Go to step 2.


	NO

Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.?

BSI alert indicator check:

BSI alert indicator check

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Disconnect the following connector.

Left BSI alert indicator 2P connector

Right BSI alert indicator 2P connector

?3.

Connect terminals 1 and body ground with a jumper wire.

Test condition	Vehicle OFF (LOCK) mode
	Left BSI alert indicator 2P connector: disconnected
	Right BSI alert indicator 2P connector: disconnected
Test point 1	Left BSI alert indicator 2P connector (female terminals) No. 1:
Test point 2	Body ground

Test point 1	Right BSI alert indicator 2P connector (female terminals) No. 1:
Test point 2	Body ground

?4.	Turn the vehicle to the ON mode.

?5.

Check for DTCs with the HDS.

DTC Description	DTC
B18C7 Open in the left side BSI radar unit indicator circuit
B1E77 Open in the right side BSI radar unit indicator circuit
B18C5 Short to GND in the left side BSI radar unit indicator circuit
B1E75 Short to GND in the right side BSI radar unit indicator circuit

Is DTC B18C7 change to DTC B18C5, or DTC B1E77 change to B1E75?


	YES

Go to step 3.


	NO

Go to step 4.

Open wire check (GND line):

Open wire check (GND line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Remove the jumper wire from the BSI alert indicator 2P connector.

?3.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Left side BSI radar unit 6P connector: disconnected
	Right side BSI radar unit 6P connector: disconnected
	Left BSI alert indicator 2P connector: disconnected
	Right BSI alert indicator 2P connector: disconnected
Test point 1	Left BSI alert indicator 2P connector (female terminals) No. 2:
Test point 2	Body ground

Test point 1	Right BSI alert indicator 2P connector (female terminals) No. 2:
Test point 2	Body ground

Is there continuity?


	YES

Replace the appropriate BSI alert indicator.?


	NO

Repair an open in the wire between the BSI alert indicator and the body ground at G401 (left BSI alert indicator), G402 (right BSI alert indicator).?

Open wire check (BSI L IND, BSI R IND lines):

Open wire check (BSI L IND, BSI R IND lines)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Remove the jumper wire from the BSI alert indicator 2P connector.

?3.

Disconnect the following connector.

Left side BSI radar unit 6P connector

Right side BSI radar unit 6P connector

?4.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Left side BSI radar unit 6P connector: disconnected
	Right side BSI radar unit 6P connector: disconnected
	Left BSI alert indicator 2P connector: disconnected
	Right BSI alert indicator 2P connector: disconnected
Test point 1	Left side BSI radar unit 6P connector No. 2
Test point 2	Left BSI alert indicator 2P connector (female terminals) No. 1:

Test point 1	Right side BSI radar unit 6P connector No. 2
Test point 2	Right BSI alert indicator 2P connector (female terminals) No. 1:

Is there continuity?


	YES

Replace the appropriate BSI radar unit.?


	NO

Repair an open in the wire between the BSI radar unit and the BSI alert indicator.?