NHTSA ID Number: 10173985
Manufacturer Communication Number: T-TT-0520-19
TSB/Document Date: 2020-04-20
Summary
TT: In certain cases of leaking air conditioning systems, the root cause of the leak is inadvertently overlooked, causing a repeat repair. To improve customer satisfaction and repair A/C system leaks in one dealer visit, Toyota
has developed a set of guidelines for evaluating A/C system components.
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Service Category
Section
Vehicle Interior
Heating/Air Conditioning
Applicability
Toyota
APPLICABLE VEHICLES
2016-2021
2015
2015-2018
2015-2021
2020-2021
2015-2021
2016-2021
2015-2021
2015-2021
2018
2015-2021
2015-2019
2015-2021
2015-2016
2015-2021
Mirai
Prius PHV
Prius V
Tundra
Corolla HV
RAV4
RAV4 HV
Prius C
Camry
Mirai (Canada)
Avalon HV
Yaris
Highlander HV
Venza
Corolla
2015-2021
2015-2021
2017-2018
2015-2021
2017-2021
2019-2021
2015-2021
2015-2020
2015-2021
2015-2021
2015-2021
2017-2020
2015-2021
2017-2021
2015-2021
Land Cruiser
Hilux
iM
Avanza
Yaris THAI-Prod
Corolla Hatchback
Camry HV
Sienna
Prius
Avalon
Highlander
86
4Runner
Prius Prime
Sequoia
CONDITION
In certain cases of leaking air conditioning systems, the root cause of the leak is inadvertently
overlooked, causing a repeat repair. To improve customer satisfaction and repair A/C system leaks
in one dealer visit, Toyota has developed a set of guidelines for evaluating A/C system components.
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Rev2
© 2018, Toyota Motor Sales, USA
Page 1 of 7
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Applicability
RECOMMENDATIONS
2) Inspect for O-ring Abnormality
• Remove the O-ring from pipe/component for
inspection.
• Using a plastic pick tool to remove O-ring
and prevent damage to mating part.
Use a non-metallic
tool for
O-ring removal.
Using a metallic
tool could result in
damage to other
components
OK Part* - Line at middle of O-ring is straight with
no deformation. No tears, or crushed areas.
*O-rings should be replaced anytime they are
removed from a pipe/component to prevent leaks
and foreign material.
Twisted O-Ring – No Good Part
Line at middle of O-ring is not straight.
Cut/Dent/Crush – No Good Part
O-ring damaged by another component.
Replace O-ring, proceed with A/C Pipe
Inspection.
Foreign Material– No Good Part
O-ring contaminated by material outside A/C
system.
Replace O-ring, proceed with A/C Pipe
inspection.
Step 2:
Inspect
O-Ring
Complete
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Step 3:
Inspect
A/C Pipe
(Cont. to pg. 3)
Rev2
© 2018, Toyota Motor Sales, USA
Page 2 of 7
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Applicability
3) - Inspect for A/C Pipe Abnormality
OK Part - Light scratching parallel with O-ring
groove. This is caused by normal part
processing. Pipe is ok to reuse.
Damage – No Good Part
Pipe is damaged due to deep
scratching or gouge of base
metal. Pipe replacement is
recommended to prevent repeat
repair.
Foreign Material – OK Part
Pipe has foreign material stuck
to it. Material can be cleaned off
using a non-metallic tool and the
pipe is ok to be reused.
Corrosion – No Good Part
Pipe is damaged due to
corrosion of base material. Pipe
replacement is recommended to
prevent repeat repair.
Step 4:
Inspect Mating
Components
(Cont. to pg. 4,5,6)
Step 3:
Inspect
A/C Pipe
Complete
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Rev2
•
•
•
4a - Compressor Inspection – Pg.4
4b - Expansion Valve – Pg. 5
4c - Condenser Inspection – Pg.6
© 2018, Toyota Motor Sales, USA
Page 3 of 7
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Applicability
4a) - Inspect for A/C Compressor Abnormality
OK Part - Light scratching parallel with O-ring groove.
This is caused by normal part processing. Compressor is
ok to reuse.
Damage – No Good Part
Compressor seal bore is damaged
due to deep scratching
perpendicular to O-ring groove.
Compressor replacement is
recommended to prevent repeat
repair.
Foreign Material – OK Part
Compressor has foreign material
stuck to seal bore.
Material can be carefully cleaned
off using a non-metallic tool and
the compressor is ok to be reused.
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Rev2
© 2018, Toyota Motor Sales, USA
Page 4 of 7
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Applicability
4b) - Inspect for Expansion Valve Abnormality
OK Part - Light scratching parallel with O-ring
groove. This is caused by normal part processing.
Expansion valve is ok to reuse.
Damage – No Good Part
Expansion valve seal bore is
damaged due to deep scratching
perpendicular to O-ring groove.
Expansion valve replacement is
recommended to prevent repeat
repair.
Foreign Material – OK Part
Expansion Valve has foreign
material stuck to seal bore.
Material can be carefully cleaned
off using a non-metallic tool and
the expansion valve is ok to be
reused.
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Rev2
© 2018, Toyota Motor Sales, USA
Page 5 of 7
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Applicability
4c) - Inspect for Condenser Abnormality
OK Part - Light scratching parallel with O-ring groove. This is
caused by normal part processing. Condenser is ok to reuse.
Damage – No Good Part
Condenser seal bore is damaged
due to deep scratching perpendicular
to O-ring groove.
Condenser replacement is
recommended to prevent repeat
repair.
Foreign Material – OK Part
Condenser has foreign material
stuck to seal bore.
Material can be carefully cleaned
off using a non-metallic tool and the
condenser is ok to be reused.
Corrosion – No Good Part
Seal bore is damaged due to
corrosion of base material.
Condenser replacement is
recommended to prevent repeat
repair.
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Rev2
© 2018, Toyota Motor Sales, USA
Page 6 of 7
Tech Tip T-TT-0520-19
March 26, 2020
Subject
Market
Air Conditioning System - Improved Component
Inspection
USA
Applicability
LINK REFERENCES
This Tech Tip does not contain any link references
Expires on
Ver. 2.9 01/01/2018 L
03/26/2021
Rev2
© 2018, Toyota Motor Sales, USA
Page 7 of 7
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TSB/Document ID: T-TT-0520-19
Replacement Service Bulletin Number:
MFR Communication Date: 2020-03-26
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: EQUIPMENT:APPLIANCE:AIR CONDITIONER
MFR Component System:
MFR Component Subsystem:
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