L-SB-0105-12

October 8, 2012

Integration Relay Poor Ground
Service
Category

Power Source/Network

Section

Power Distribution

Market

USA

Applicability
YEAR(S)

MODEL(S)

2013

ES300H

2013

ES350

ADDITIONAL INFORMATION

Introduction

Some 2013 model year ES 350 and ES 300h vehicles may exhibit a condition where the passenger
headlight and rear defogger operate continuously.
This condition may be caused by a poor ground for the Engine Room Junction Block Assembly on
the left fender side panel bracket after a collision repair. This may occur during body shop repairs or
other repairs where the left side fender bracket grounds were left loose, not properly attached using
correct bolts, or improperly painted, and the vehicle’s battery was connected.
NOTICE
BEFORE performing work on electronic components, components including grounds, or fender
brackets with grounds, disconnect the cable from the negative (–) battery terminal to prevent
damage to the electrical system or components.

Parts Information
PREVIOUS PART NUMBER

CURRENT PART NUMBER

PART NAME

QTY

53804-33040

Same

Bracket, Front Side Panel, LH

1

82720-33350

Same

82720-33380

Same

82720-33390

Same

1
1

Block Assy, Engine Room Junction

1

Warranty Information
OP CODE

DESCRIPTION

TIME

OFP

T1

T2

N/A

Not Applicable to Warranty

–

–

–

–

© 2013 Lexus, a division of Toyota Motor Sales, USA

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Integration Relay Poor Ground

Required Tools & Equipment
SPECIAL SERVICE TOOLS (SST)

PART NUMBER

QTY

GR8 Battery Diagnostic Station*

00002-MCGR8

1

NOTE
Additional SSTs may be ordered by calling 1-800-933-8335.
* Essential SST.

Repair Procedure
CAUTION
At NO time should the battery be connected when any ground attachments (A1, A2, apron bolts, or
front side panel bracket) are loose.

1. Has the vehicle had body work or the A1/A2 grounds, or apron mounting bolts disconnected?
• YES / UNSURE — Continue to step 2.
• NO — This bulletin does NOT apply. Continue diagnosis using the applicable Repair Manual.
Figure 1.

Figure 2.

1

1

A1
A2

1

A1

A1 Ground

A2

A2 Ground

Apron Bolts

© 2013 Lexus, a division of Toyota Motor Sales, USA

L-SB-0105-12

October 8, 2012

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Integration Relay Poor Ground

Repair Procedure (Continued)

2. Disconnect the negative (–) battery terminal.
3. Charge the battery with the GR8 Battery Diagnostic Station until charge is over 12 volts.
4. Remove the front bumper cover and left headlight assembly.
Refer to the Technical Information System (TIS), applicable model and model year Repair
Manual:
• Bumper Cover:
2013 ES 350 / ES 300h:
Vehicle Exterior – Exterior Panels/Trim – “Exterior Panels/Trim: Front Bumper:
Removal”
• Left Headlight Assembly:
2013 ES 350 / ES 300h:
Vehicle Exterior – Lighting (ext) – “Lighting (Ext): Headlight Assembly:
Removal”
5. Visually inspect the wiring harness at the Engine Room Junction Block Assembly for physical
damage.
Is there physical damage to the wiring harness?
• YES — Replace the affected harness(es). Once replaced, continue to step 6.
• NO — Continue to step 6.
6. Reconnect the battery and verify passenger headlight is ON and rear defogger is warm.
• If YES — Continue to step 7.
• If NO — This bulletin does NOT apply. Continue diagnosis using the applicable Repair
Manual.
NOTICE
• When the rear defogger grid is warm to the touch and the right side headlamp is ON when
the key is OFF, or the cooling fans are running continuously, please remove the negative
(–) battery terminal to prevent additional damage as soon as testing is complete.
• Vehicles exhibiting these conditions should not be left unattended before or after testing
unless the negative (–) battery terminal is disconnected.

© 2013 Lexus, a division of Toyota Motor Sales, USA

L-SB-0105-12

October 8, 2012

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Integration Relay Poor Ground

Repair Procedure (Continued)

7. Perform voltage drop test* from the two left fender bracket ground wire eyelet tabs to body
ground (see Figure 3).
* For detailed information on performing the voltage drop test, please refer to the Quick Training Guide
“QL611A: Body Electrical Diagnosis” found on the Technical Information System (TIS),
under Technical Training – QTG – Skill Area: Electrical & A/C.
CAUTION
At NO time should the battery be connected when any ground attachments (A1, A2, or apron
mounting bolts) are loose.

A. Use a left front strut tower mounting bolt as a good body ground (see Figure 4).
B. To perform voltage drop test, connect the negative lead of the DVOM to the strut tower bolt,
and the positive lead to the ground wire eyelet tab.
Figure 3.

Figure 4.

8. Is voltage drop from each ground location less than 0.2 volts?
• YES — This bulletin does NOT apply. Continue diagnosis using the applicable Repair
Manual.
• NO — A voltage drop of 0.2 volts or more from either of the ground locations may indicate
poor continuity in the ground circuit. Proceed to step 9.
9. With battery disconnected, remove the left hand fender bracket from the apron for inspection.

© 2013 Lexus, a division of Toyota Motor Sales, USA

L-SB-0105-12

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Integration Relay Poor Ground

Repair Procedure (Continued)

10. Inspect the grounds on the left hand fender bracket. Confirm the following:
• Ground bolts are “E” bolts (see Figures 5 and 7).
• Apron bolts should be “E” bolts if left hand fender bracket has been replaced (see Figures 5
and 7).
• The area around the bracket to apron mounting bolt holes (see Figure 6) is free of paint.
• The area around the apron mounting bolt holes do not show masking tape or painted
masking tape (see Figures 5 and 6).
If ALL conditions above are met, continue with diagnosis using the applicable Repair Manual.
If ANY of the conditions above are NOT met, continue to step 11.
NOTICE
• Do NOT drive the vehicle or hook up the battery without proper "E" bolts in all 4 locations
at apron and both grounds. The fender bracket must have a good ground path to prevent
Engine Room Junction Block damage.
•

Do NOT remove the fender bracket or grounds without first disconnecting the negative (–)
battery cable.
Figure 6.

Figure 5.
1

1
2

1

Confirm Green Masking Tape Is Removed

2

Confirm “E” Bolts Are Installed

1

Masking Tape — REMOVE After Painting,
NO Paint in This Area

© 2013 Lexus, a division of Toyota Motor Sales, USA

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Integration Relay Poor Ground

Repair Procedure (Continued)
Figure 7.

NOTE
• It is important that the bracket to
apron mounting bolts/washers are
free of paint on the front portion of
the bracket.

2

1

• The new part number bracket comes
with instructions that should be
followed carefully when replacing.
• The new bracket also comes
with green tape around the apron
mounting bolts to protect it during
the painting phase (see Figures 5
and 6). This green masking tape
MUST be removed in order for the
bracket to be properly installed on
the vehicle.

1

Old Bolt: DO NOT USE or Reuse These Bolts

2

NEW “E” Bolt

• The new bracket includes new apron
“E” mounting bolts. It is important
that the new “E” bolts are used and
are torqued properly. See Figure 7
on how to identify new bolts.
Torque: Ground Bolts:
6.9 – 9.8 N*m (70 – 100 kgf*cm,
5.1 – 7.2 ft*lbf)
Torque: Bracket to Apron Bolts:
3.9 – 8.8 N*m (40 – 90 kgf*cm,
2.8 – 6.5 ft*lbf)

11. Is there masking tape or painted masking tape or paint around the apron bolt holes?
• NO — Replace the left hand fender bracket.
• YES — Remove the tape or paint and continue to step 12.
NOTE
Apply cavity wax to apron bolts and area surrounding washers once bracket is completely
installed.

12. Once areas are repaired and secured with new “E” bolts, replace the Engine Room Junction
Block Assembly.

© 2013 Lexus, a division of Toyota Motor Sales, USA

L-SB-0105-12

October 8, 2012

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Integration Relay Poor Ground

Repair Procedure (Continued)

13. Reconnect battery, verify passenger headlight and rear defogger are OFF, then perform another
voltage drop test from both ground wire tabs to a strut tower bolt and verify the voltage drop is
less than 0.2 volts.
Is voltage drop less than 0.2 volts?
• YES — Continue to step 14.
• NO — Go back to step 10.
14. Reinstall front bumper cover and left headlight assembly.
Refer to TIS, applicable model and model year Repair Manual:
• Bumper Cover:
2013 ES 350 / ES 300h:
Vehicle Exterior – Exterior Panels/Trim – “Exterior Panels/Trim: Front Bumper:
Installation”
• Left Headlight Assembly:
2013 ES 350 / ES 300h:
Vehicle Exterior – Lighting (ext) – “Lighting (Ext): Headlight Assembly:
Installation”
15. Verify all affected systems work properly.

© 2013 Lexus, a division of Toyota Motor Sales, USA