Toyota CH-R Service Manual: Manual Cut off Switch Trouble (B1651/33)

DESCRIPTION

The airbag cut off switch circuit consists of the airbag sensor assembly and airbag cut off switch cylinder sub-assembly.

The instrument panel passenger without door airbag assembly can be optionally deactivated via this circuit by turning the airbag cut off switch cylinder sub-assembly to the OFF position.

If the instrument panel passenger without door airbag assembly is deactivated, the passenger airbag ON/OFF indicator ("OFF") comes on to inform the driver.

DTC B1651/33 is stored when a malfunction is detected in the airbag cut off switch circuit.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Test Mode / Check Mode
B1651/33	Manual Cut off Switch Trouble	Any of the following conditions is met: The airbag sensor assembly detects a line short, in the airbag cut off switch circuit. The airbag sensor assembly detects a short to ground in the airbag cut off switch circuit. The airbag sensor assembly detects a short to B+ in the airbag cut off switch circuit. The airbag sensor assembly detects an open in the airbag cut off switch circuit. Airbag cut off switch cylinder sub-assembly malfunction Airbag sensor assembly malfunction	Instrument panel wire Airbag cut off switch cylinder sub-assembly Airbag sensor assembly	Does not apply to test/check mode

DTC Detection Conditions:

		Vehicle Condition
		Pattern 1	Pattern 2	Pattern 3	Pattern 4	Pattern 5	Pattern 6
Diagnosis Condition	Ignition switch ON	○	○	○	○	○	○
Malfunction Status	The airbag sensor assembly detects a line short, in the airbag cut off switch circuit	○	-	-	-	-	-
	The airbag sensor assembly detects a short to ground in the airbag cut off switch circuit	-	○	-	-	-	-
	The airbag sensor assembly detects a short to B+ in the airbag cut off switch circuit	-	-	○	-	-	-
	The airbag sensor assembly detects an open in the airbag cut off switch circuit	-	-	-	○	-	-
	Airbag cut off switch cylinder sub-assembly malfunction	-	-	-	-	○	-
	Airbag sensor assembly malfunction	-	-	-	-	-	○
Detection Time		-	-	-	-	-	-
Number of Trips		1 trip	1 trip	1 trip	1 trip	1 trip	1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

Click here

HINT:

Terminals F70-11 (MSW+) and F70-12 (MSW-) of the instrument panel wire in this circuit have an activation prevention mechanism.

This mechanism can be used to check for an open circuit in the wire harness. When performing other checks (check for short, short to ground or short to B+), this mechanism should be released.

PROCEDURE

1.	CHECK CONNECTORS

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connectors are properly connected to the airbag sensor assembly and airbag cut off switch cylinder sub-assembly.

OK:

The connectors are properly connected.

HINT:

If the connectors are not properly connected, reconnect the connectors and proceed to the next inspection.

(d) Disconnect the connectors from the airbag sensor assembly and airbag cut off switch cylinder sub-assembly.

(e) Check that the terminals of the connectors are not deformed or damaged.

OK:

The terminals are not deformed or damaged.

(f) Check that the short springs of the activation prevention mechanism of the instrument panel wire connector are not deformed or damaged.

OK:

The short springs are not deformed or damaged.

NG

REPLACE INSTRUMENT PANEL WIRE

OK

2.	CHECK INSTRUMENT PANEL WIRE (OPEN)

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition F64-2 (PMC+) - F64-1 (PMC-) Always Below 1 Ω

*1 Airbag Cut Off Switch Cylinder Sub-assembly *2 Airbag Sensor Assembly *3 Instrument Panel Wire *a Front view of wire harness connector (to Airbag Cut Off Switch Cylinder Sub-assembly)

NG

REPLACE INSTRUMENT PANEL WIRE

OK

3.	CHECK INSTRUMENT PANEL WIRE (SHORT)

(a) Release the activation prevention mechanism built into connector B. Click here

*1 Airbag Cut Off Switch Cylinder Sub-assembly *2 Airbag Sensor Assembly *3 Instrument Panel Wire *a Front view of wire harness connector (to Airbag Cut Off Switch Cylinder Sub-assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
F64-2 (PMC+) - F64-1 (PMC-)	Always	1 MΩ or higher

NG

REPLACE INSTRUMENT PANEL WIRE

OK

4.	CHECK INSTRUMENT PANEL WIRE (SHORT TO B+)

(a) Connect the cable to the negative (-) battery terminal.

*1 Airbag Cut Off Switch Cylinder Sub-assembly *2 Airbag Sensor Assembly *3 Instrument Panel Wire *a Front view of wire harness connector (to Airbag Cut Off Switch Cylinder Sub-assembly)

(b) Turn the ignition switch ON.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
F64-2 (PMC+) - Body ground	Ignition switch ON	Below 1 V
F64-1 (PMC-) - Body ground	Ignition switch ON	Below 1 V

(d) Turn the ignition switch off.

(e) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

NG

REPLACE INSTRUMENT PANEL WIRE

OK

5.	CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition F64-2 (PMC+) - Body ground Always 1 MΩ or higher F64-1 (PMC-) - Body ground Always 1 MΩ or higher

*1 Airbag Cut Off Switch Cylinder Sub-assembly *2 Airbag Sensor Assembly *3 Instrument Panel Wire *a Front view of wire harness connector (to Airbag Cut Off Switch Cylinder Sub-assembly)

(b) Restore the released activation prevention mechanism of connector B to the original condition.

NG

REPLACE INSTRUMENT PANEL WIRE

OK

6.	CHECK AIRBAG CUT OFF SWITCH CYLINDER SUB-ASSEMBLY

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Switch Condition Specified Condition 2 (PMC+) - 1 (PMC-) Cut off switch in ON position 360 to 440 Ω 2 (PMC+) - 1 (PMC-) Cut off switch in OFF position 90 to 110 Ω

*a Component without harness connected (Airbag Cut Off Switch Cylinder Sub-assembly)

NG

REPLACE AIRBAG CUT OFF SWITCH CYLINDER SUB-ASSEMBLY

OK

7.

CHECK DTC

(a) Connect the connectors to the airbag sensor assembly and airbag cut off switch cylinder sub-assembly.

*1 Airbag Cut Off Switch Cylinder Sub-assembly *2 Airbag Sensor Assembly

(b) Connect the cable to the negative (-) battery terminal.

(c) Clear the DTCs stored in memory.

Click here

Body Electrical > SRS Airbag > Clear DTCs

(d) Turn the ignition switch off.

(e) Turn the ignition switch ON, and wait for at least 60 seconds.

(f) Check for DTCs.

Click here

Body Electrical > SRS Airbag > Trouble Codes

OK:

DTC B1651/33 is not output.

HINT:

Codes other than DTC B1651/33 may be output at this time, but they are not related to this check.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE AIRBAG SENSOR ASSEMBLY