Last Modified: 07-31-2024 |
6.11:8.1.0 |
Doc ID: RM100000001I0V1 |
Model Year Start: 2020 |
Model: GR Corolla |
Prod Date Range: [03/2019 - 09/2022] |
Title: METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM (for Gasoline Model): B150718; Turn Signal Light Circuit Current Below Threshold; 2020 - 2022 MY Corolla Corolla Hatchback GR Corolla [03/2019 - 09/2022] |
DTC
|
B150718
|
Turn Signal Light Circuit Current Below Threshold
|
DESCRIPTION
This DTC is stored when the combination meter assembly detects an open in a front turn signal light circuit or rear turn signal light circuit.
HINT:
-
If there is an open in a front turn signal light circuit or rear turn signal light circuit, the turn signal lights on the side with the open circuit will blink faster than usual.
-
If there is an open in a side turn signal light circuit, DTC B150718 will not be stored.
DTC No.
|
Detection Item
|
DTC Detection Condition
|
Trouble Area
|
B150718
|
Turn Signal Light Circuit Current Below Threshold
|
Diagnosis Condition:
-
Battery voltage is 10 V or more
Malfunction Status:
-
Open in front turn signal light circuit
-
Open in rear turn signal light circuit
|
-
Harness or connector
-
Combination meter assembly
for TMC Made
-
Headlight ECU sub-assembly*1
-
Headlight unit assembly*2
-
Front turn signal light socket*3
-
Front turn signal light bulb*3
-
Rear combination light cord
-
Rear combination light LED LH*4
-
Rear combination light LED RH*4
-
Rear turn signal light bulb*5
for TMMMS Made
-
Headlight assembly*2
-
Front turn signal light socket*3
-
Front turn signal light bulb*3
-
Rear combination light cord
-
Rear turn signal light bulb
|
-
*1: w/ AFS
-
*2: for LED Type Front Turn Signal Light
-
*3: for Bulb Type Front Turn Signal Light
-
*4: for LED Type Rear Turn Signal Light
-
*5: for Bulb Type Rear Turn Signal Light
WIRING DIAGRAM
FOR TMC MADE
FOR TMMMS MADE
CAUTION / NOTICE / HINT
NOTICE:
-
When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
-
When replacing the headlight ECU sub-assembly LH, always replace it with a new one. If a headlight ECU sub-assembly LH which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.*
-
Inspect the turn signal light bulbs before performing the following procedure.
PROCEDURE
(a) Check the problem symptoms.
Result
|
Proceed to
|
LH side front turn signal light does not blink
|
A
|
LH side rear turn signal light does not blink
|
B
|
RH side front turn signal light does not blink
|
C
|
RH side rear turn signal light does not blink
|
D
|
A
|
|
|
(a) Choose the model to be inspected.
Result
|
Proceed to
|
Specifications
|
Front Turn Signal Light
|
for TMC Made
|
LED Type
(w/ AFS)
|
A
|
LED Type
(w/o AFS)
|
B
|
Bulb Type
|
C
|
for TMMMS Made
|
LED Type
|
D
|
Bulb Type
|
E
|
A
|
|
|
3.
|
INSPECT HEADLIGHT CORD (HEADLIGHT UNIT ASSEMBLY LH)
|
*1
|
Headlight Cord (Headlight Unit Assembly LH)
|
-
|
-
|
*a
|
Component without harness connected
(Headlight ECU Sub-assembly LH)
|
*b
|
Component without harness connected
(to Wire Harness)
|
(a) Disconnect the B, A21 and A23 headlight cord (headlight unit assembly LH) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
B-11 (ECUB) - A21-1 (TNS)
|
Always
|
Below 1 Ω
|
B-12 (GND) - A23-4 (GND)
|
Always
|
Below 1 Ω
|
OK
|
|
|
4.
|
INSPECT HEADLIGHT ECU SUB-ASSEMBLY LH
|
*a
|
Component without harness connected
(Headlight ECU Sub-assembly LH)
|
-
|
-
|
(a) Remove the headlight ECU sub-assembly LH.
Click here
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
C-20 (TURN+) - B-11 (ECUB)
|
Always
|
Below 1 Ω
|
C-13 (TURN-) - B-12 (GND)
|
Always
|
Below 1 Ω
|
OK
|
|
|
5.
|
CHECK LH SIDE FRONT TURN SIGNAL LIGHT (TURN SIGNAL LIGHT (HEADLIGHT UNIT ASSEMBLY LH))
|
(a) Interchange the turn signal light (headlight unit assembly) LH with RH and connect the connectors.
Click here
(b) Connect the headlight cord (headlight unit assembly LH) connectors.
(c) Connect the headlight ECU sub-assembly LH connectors.
(d) Operate the turn signal switch and check that the LH side front turn signal light operates normally.
HINT:
If the LH side front turn signal light operates normally, the turn signal light (headlight unit assembly LH) is malfunctioning.
Result
|
Proceed to
|
LH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(LH side front turn signal light does not blink)
|
B
|
B
|
|
|
6.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY LH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A21 and A23 headlight assembly LH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A21-1 (TNS) - I5-1 (LL)
|
Always
|
Below 1 Ω
|
A23-4 (GND) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
7.
|
CHECK LH SIDE FRONT TURN SIGNAL LIGHT (HEADLIGHT UNIT ASSEMBLY LH)
|
(a) Interchange the headlight unit assembly LH with RH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the LH side front turn signal light operates normally.
HINT:
If the LH side front turn signal light operates normally, the headlight unit assembly LH is malfunctioning.
Result
|
Proceed to
|
LH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(LH side front turn signal light does not blink)
|
B
|
8.
|
CHECK LH SIDE FRONT TURN SIGNAL LIGHT (FRONT TURN SIGNAL LIGHT SOCKET LH)
|
(a) Interchange the front turn signal light socket LH with RH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the LH side front turn signal light operates normally.
HINT:
If the LH side front turn signal light operates normally, the front turn signal light socket LH is malfunctioning.
Result
|
Proceed to
|
LH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(LH side front turn signal light does not blink)
|
B
|
B
|
|
|
9.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY LH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A90 headlight assembly LH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A90-1 (B) - I5-1 (LL)
|
Always
|
Below 1 Ω
|
A90-2 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
10.
|
CHECK LH SIDE FRONT TURN SIGNAL LIGHT (HEADLIGHT ASSEMBLY LH)
|
(a) Interchange the headlight assembly LH with RH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the LH side front turn signal light operates normally.
HINT:
If the LH side front turn signal light operates normally, the headlight assembly LH is malfunctioning.
Result
|
Proceed to
|
LH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(LH side front turn signal light does not blink)
|
B
|
B
|
|
|
11.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY LH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A83 headlight assembly LH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A83-2 (B) - I5-1 (LL)
|
Always
|
Below 1 Ω
|
A83-3 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
12.
|
CHECK LH SIDE FRONT TURN SIGNAL LIGHT (FRONT TURN SIGNAL LIGHT SOCKET LH)
|
(a) Interchange the front turn signal light socket LH with RH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the LH side front turn signal light operates normally.
HINT:
If the LH side front turn signal light operates normally, the front turn signal light socket LH is malfunctioning.
Result
|
Proceed to
|
LH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(LH side front turn signal light does not blink)
|
B
|
B
|
|
|
13.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY LH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A122 headlight assembly LH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A122-1 (B) - I5-1 (LL)
|
Always
|
Below 1 Ω
|
A122-3 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
(a) Choose the model to be inspected.
Result
|
Proceed to
|
for Bulb Type Rear Turn Signal Light
|
A
|
for LED Type Rear Turn Signal Light
|
B
|
A
|
|
|
15.
|
CHECK LH SIDE REAR TURN SIGNAL LIGHT (REAR COMBINATION LIGHT CORD LH)
|
(a) Interchange the rear combination light cord LH with RH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the LH side rear turn signal light operates normally.
HINT:
If the LH side rear turn signal lights operates normally, the rear combination light cord LH is malfunctioning.
Result
|
Proceed to
|
LH side rear turn signal lights operates normally
|
A
|
Problem symptoms do not change
(LH side rear turn signal light does not blink)
|
B
|
B
|
|
|
16.
|
CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT ASSEMBLY LH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the O104 rear combination light assembly LH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
O104-3 (B) - I5-5 (TRNL)
|
Always
|
Below 1 Ω
|
O104-4 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
17.
|
CHECK LH SIDE REAR TURN SIGNAL LIGHT (REAR COMBINATION LIGHT ASSEMBLY LH)
|
(a) Interchange the rear combination light assembly LH with RH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the LH side rear turn signal light operates normally.
HINT:
If the LH side rear turn signal lights operates normally, a component of the rear combination light assembly LH is malfunctioning.
Result
|
Proceed to
|
LH side rear turn signal lights operates normally
|
A
|
Problem symptoms do not change
(LH side rear turn signal light does not blink)
|
B
|
A
|
|
|
18.
|
INSPECT REAR COMBINATION LIGHT LED LH
|
(a) Remove the rear combination light LED LH from rear combination light assembly LH.
Click here
(b) Inspect the rear combination light LED LH.
Click here
19.
|
CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT ASSEMBLY LH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the O43 rear combination light assembly LH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
O43-4 (B) - I5-5 (TRNL)
|
Always
|
Below 1 Ω
|
O43-3 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
(a) Choose the model to be inspected.
Result
|
Proceed to
|
Specifications
|
Front Turn Signal Light
|
for TMC Made
|
LED Type
(w/ AFS)
|
A
|
LED Type
(w/o AFS)
|
B
|
Bulb Type
|
C
|
for TMMMS Made
|
LED Type
|
D
|
Bulb Type
|
E
|
A
|
|
|
21.
|
INSPECT HEADLIGHT CORD (HEADLIGHT UNIT ASSEMBLY RH)
|
*1
|
Headlight Cord (Headlight Unit Assembly RH)
|
-
|
-
|
*a
|
Component without harness connected
(Headlight ECU Sub-assembly RH)
|
*b
|
Component without harness connected
(to Wire Harness)
|
(a) Disconnect the D, A20 and A22 headlight cord (headlight unit assembly RH) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
D-11 (ECUB) - A20-1 (TNS)
|
Always
|
Below 1 Ω
|
D-12 (GND) - A22-4 (GND)
|
Always
|
Below 1 Ω
|
OK
|
|
|
22.
|
INSPECT HEADLIGHT ECU SUB-ASSEMBLY RH
|
*a
|
Component without harness connected
(Headlight ECU Sub-assembly RH)
|
-
|
-
|
(a) Remove the headlight ECU sub-assembly RH.
Click here
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
E-20 (TURN+) - D-11 (ECUB)
|
Always
|
Below 1 Ω
|
E-13 (TURN-) - D-12 (GND)
|
Always
|
Below 1 Ω
|
OK
|
|
|
23.
|
CHECK RH SIDE FRONT TURN SIGNAL LIGHT (TURN SIGNAL LIGHT (HEADLIGHT UNIT ASSEMBLY RH))
|
(a) Interchange the turn signal light (headlight unit assembly) RH with LH and connect the connectors.
Click here
(b) Connect the headlight cord (headlight unit assembly RH) connectors.
(c) Connect the headlight ECU sub-assembly RH connectors.
(d) Operate the turn signal switch and check that the RH side front turn signal light operates normally.
HINT:
If the RH side front turn signal light operates normally, the turn signal light (headlight unit assembly RH) is malfunctioning.
Result
|
Proceed to
|
RH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(RH side front turn signal light does not blink)
|
B
|
B
|
|
|
24.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY RH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A20 and A22 headlight assembly RH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A20-1 (TNS) - I5-2 (LR)
|
Always
|
Below 1 Ω
|
A22-4 (GND) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
25.
|
CHECK RH SIDE FRONT TURN SIGNAL LIGHT (HEADLIGHT UNIT ASSEMBLY RH)
|
(a) Interchange the headlight unit assembly RH with LH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the RH side front turn signal light operates normally.
HINT:
If the RH side front turn signal light operates normally, the headlight unit assembly RH is malfunctioning.
Result
|
Proceed to
|
RH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(RH side front turn signal light does not blink)
|
B
|
26.
|
CHECK RH SIDE FRONT TURN SIGNAL LIGHT (FRONT TURN SIGNAL LIGHT SOCKET RH)
|
(a) Interchange the front turn signal light socket RH with LH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the RH side front turn signal light operates normally.
HINT:
If the RH side front turn signal light operates normally, the front turn signal light socket RH is malfunctioning.
Result
|
Proceed to
|
RH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(RH side front turn signal light does not blink)
|
B
|
B
|
|
|
27.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY RH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A87 headlight assembly RH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A87-1 (B) - I5-2 (LR)
|
Always
|
Below 1 Ω
|
A87-2 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
28.
|
CHECK RH SIDE FRONT TURN SIGNAL LIGHT (HEADLIGHT ASSEMBLY RH)
|
(a) Interchange the headlight assembly RH with LH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the RH side front turn signal light operates normally.
HINT:
If the RH side front turn signal light operates normally, the headlight assembly RH is malfunctioning.
Result
|
Proceed to
|
RH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(RH side front turn signal light does not blink)
|
B
|
B
|
|
|
29.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY RH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A82 headlight assembly RH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A82-2 (B) - I5-2 (LR)
|
Always
|
Below 1 Ω
|
A82-3 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
30.
|
CHECK RH SIDE FRONT TURN SIGNAL LIGHT (FRONT TURN SIGNAL LIGHT SOCKET RH)
|
(a) Interchange the front turn signal light socket RH with LH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the RH side front turn signal light operates normally.
HINT:
If the RH side front turn signal light operates normally, the front turn signal light socket RH is malfunctioning.
Result
|
Proceed to
|
RH side front turn signal light operates normally
|
A
|
Problem symptoms do not change
(RH side front turn signal light does not blink)
|
B
|
B
|
|
|
31.
|
CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY RH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the A121 headlight assembly RH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A121-1 (B) - I5-2 (LR)
|
Always
|
Below 1 Ω
|
A121-3 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
(a) Choose the model to be inspected.
Result
|
Proceed to
|
for Bulb Type Rear Turn Signal Light
|
A
|
for LED Type Rear Turn Signal Light
|
B
|
A
|
|
|
33.
|
CHECK RH SIDE REAR TURN SIGNAL LIGHT (REAR COMBINATION LIGHT CORD RH)
|
(a) Interchange the rear combination light cord RH with LH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the RH side rear turn signal light operates normally.
HINT:
If the RH side rear turn signal lights operates normally, the rear combination light cord RH is malfunctioning.
Result
|
Proceed to
|
RH side rear turn signal lights operates normally
|
A
|
Problem symptoms do not change
(RH side rear turn signal light does not blink)
|
B
|
B
|
|
|
34.
|
CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT ASSEMBLY RH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the O103 rear combination light assembly RH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
O103-3 (B) - I5-6 (TRNR)
|
Always
|
Below 1 Ω
|
O103-4 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
35.
|
CHECK RH SIDE REAR TURN SIGNAL LIGHT (REAR COMBINATION LIGHT ASSEMBLY RH)
|
(a) Interchange the rear combination light assembly RH with LH and connect the connectors.
Click here
(b) Operate the turn signal switch and check that the RH side rear turn signal light operates normally.
HINT:
If the RH side rear turn signal lights operates normally, a component of the rear combination light assembly RH is malfunctioning.
Result
|
Proceed to
|
RH side rear turn signal lights operates normally
|
A
|
Problem symptoms do not change
(RH side rear turn signal light does not blink)
|
B
|
A
|
|
|
36.
|
INSPECT REAR COMBINATION LIGHT LED RH
|
(a) Remove the rear combination light LED RH from rear combination light assembly RH.
Click here
(b) Inspect the rear combination light LED RH.
Click here
37.
|
CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT ASSEMBLY RH - COMBINATION METER ASSEMBLY AND BODY GROUND)
|
(a) Disconnect the O42 rear combination light assembly RH connector.
(b) Disconnect the I5 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
O42-4 (B) - I5-6 (TRNR)
|
Always
|
Below 1 Ω
|
O42-3 (E) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
|