Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001G707
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 09/2022]
Title: METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM (for HV Model): B150718; Turn Signal Light Circuit Current Below Threshold; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 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:

  • Auxiliary battery voltage is 10 V or more

Malfunction Status:

  • Open in front turn signal light circuit
  • Open in rear turn signal light circuit
  • Headlight unit assembly
  • Rear combination light cord
  • Rear turn signal light bulb
  • Harness or connector
  • Combination meter assembly

WIRING DIAGRAM

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.
  • Inspect the turn signal light bulbs before performing the following procedure.

PROCEDURE

1.

CHECK SYMPTOMS

(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
B

GO TO STEP 4

C

GO TO STEP 6

D

GO TO STEP 8

A

2.

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 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY

(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
A

REPLACE HEADLIGHT UNIT ASSEMBLY LH 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY

B

3.

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
OK

REPLACE COMBINATION METER ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.

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 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 -        ]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL

(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
A

REPLACE REAR COMBINATION LIGHT CORD LH 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 -        ]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL

B

5.

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
OK

REPLACE COMBINATION METER ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.

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 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY

(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
A

REPLACE HEADLIGHT UNIT ASSEMBLY RH 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY

B

7.

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
OK

REPLACE COMBINATION METER ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

8.

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 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 -        ]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL

(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
A

REPLACE REAR COMBINATION LIGHT CORD RH 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 -        ]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY (for Sedan): REMOVAL

B

9.

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
OK

REPLACE COMBINATION METER ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR