Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Condition
Applicable Vehicles
Model(s)

Year

Eng. Code

Trans. Code

VIN Range
From

VIN Range To

All

2010-2021

All

All

All

All

Revision Table
Instance Number

Published Date

Version Number

2061094/1

10/29/20

87-20-02

Reason For Update
Original publication.

Diagnosing a large/medium leak with the use of Nitrogen.
Note:
This bulletin must be read in its entirety before beginning repair.

Technical Background
This bulletin explains the use of Nitrogen to aid in refrigerant leak diagnosis in cases where the refrigerant
evacuation process will not pass the vacuum test due to a large to medium leak where there is no
refrigerant in the A/C system.
This tester may speed up the diagnostic process and help identify some larger leaks without having to
recharge the system with refrigerant and dye. In most cases if the refrigerant is very low or empty there is
usually a large leak in the system.
Note:
In cases where a leak is not present using the nitrogen test further diagnosis is required. It will be
necessary to inject dye into the refrigerant circuit and recharge the system.

Production Solution
No production change required.

Service
To perform this procedure you must have the NITROKITG and (oxygen free) Nitrogen.
The nitrogen tank on KLI9210DLX Evaporative Emissions Tester can also be used with the NITROKITG.

Page 1 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Note:
Only the nitrogen tank on the KLI9210DLX should be used. The KLI9210DLX machine should not be
attached to the vehicle or damage to A/C system components will occur.
Although mentioned in Elsa Pro do not use compressed air on the refrigerant circuit. The use of
compressed air instead of nitrogen can introduce contamination and moisture into the refrigerant circuit.
Before setting up the NITROKITG on the vehicle, check for pressure in the refrigerant circuit. If there is
refrigerant in the system evacuate the refrigerant circuit using an approved R134a/R1234yf refrigerant
station.
Attach to the NITROKITG manifold to the nitrogen
tank.
Note:
If using the KLI9210DLX remove the smoke
manifold set and install the NITROKIT manifold set.
(Figures 1 and 2)

Figure1. Removing the KLI9210DLX manifold.

Page 2 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Figure 2. Installing NITROKITG manifold set.

Attach the yellow feed hose to the tank manifold
regulator and the other end to the single gauge
pressure regulator. (Figures 3 and 4)

Figure 3.

Page 3 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Note:
Pay close attention to the inlet arrow on the single
gauge pressure regulator when attaching the yellow
hose.

Figure 4.

Page 4 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Attach the red feed hose to the single gauge
pressure regulator and attach the other end to the
high side coupler valve.
Attach the high side coupler to the vehicle.
(Figure 5)

Note:
There are different high side couplers depending on
the systems refrigerant type (R1234yf or R134a).
Use the appropriate coupler based on the system
you are working on.

Figure 5.

Page 5 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Temporarily open the vehicle high side coupler to
check for any pressure in the system. (Figure 6)

Note:
If pressure is observed the refrigerant circuit is not
empty and must be evacuated in order to continue.
Repeat step 1.

Figure 6.

Close the high side coupler on the vehicle and
make sure both manifold regulators are fully closed.
Open the valve on the nitrogen tank and adjust the
manifold regulator to 200 psi (Figure 7).

Figure 7.
Page 6 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Reopen the vehicles high side coupler and slowly
start to open the single gauge regulator in 50 psi
increments.
Listen for any pressure leaks. If none are identified
increase the pressure by another 50 psi up to 200
psi. (Figure 8)

Note:
A soapy water mix can be sprayed around A/C
system joints and components in conjunction with
this kit to help pin point a leak location. Additionally,
the NITROKITG can be used with locally sourced
Tracer Gas. Using tool LDA1000H (Leak Detector)
the 5% of hydrogen that is mixed in with the
nitrogen makes it easier for the tool to detect leaks.

Figure 8.

Warranty
Information only.

Page 7 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.

Technical Service Bulletin

87-20-02 - Refrigerant Leak Diagnosis Using Nitrogen

Transaction
No:

2061094/1

Release date:

10/29/2020

Required Parts and Tools
Tool Description

Tool No:

Nitrogen test kit

NITROKITG

Compressed Nitrogen Gas

(Locally Sourced)

Additional Information
All part and service references provided in this Technical Bulletin are subject to change and/or removal.
Always check with your Parts Dept. and Repair Manuals for the latest information.

Page 8 of 8
© 2020 Volkswagen Group of America, Inc.
All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright and
other intellectual property rights of Volkswagen Group of America, Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any
time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the
publisher.