<PAGE>   1
                                                                    EXHIBIT 10.1

                  AMENDMENT NO. 3 dated as of June 15, 2001 (this "Amendment"),
amending the CREDIT AGREEMENT (as amended by Amendment No. 1 dated as of
September 25, 2000 and Amendment No. 2 dated as of November 29, 2000, the
"CREDIT AGREEMENT") dated as of November 17, 1999, among INTERLOGIX, INC., a
Delaware corporation (formerly known as ITI Technologies, Inc. and successor by
merger to SLC Technologies, Inc.) (the "DOMESTIC BORROWER"), the institutions
party thereto, PNC BANK, NATIONAL ASSOCIATION, as administrative agent for the
Banks (the "ADMINISTRATIVE AGENT"), THE BANK OF NOVA SCOTIA, as syndication
agent for the Banks, and FIRST UNION NATIONAL BANK, as Documentation Agent.

                                   BACKGROUND

                  WHEREAS, the Domestic Borrower, the Banks, and the Agents have
entered into the Credit Agreement providing for extensions of credit from time
to time to the Borrowers; and

                  WHEREAS, the Domestic Borrower has requested the Banks agree
to certain amendments to the Credit Agreement and the Banks have, subject to the
terms and conditions contained herein, agreed to such amendments;

                  NOW THEREFORE, for good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, and in consideration
of the agreements herein, the parties hereto agree as follows:

                  SECTION 1. Definitions; References. Unless otherwise
specifically defined herein, each term used herein which is defined in the
Credit Agreement shall have the meaning assigned to such term in the Credit
Agreement.

                  SECTION 2. Representations and Warranties. The Domestic
Borrower represents and warrants to the Administrative Agent that:

                  (a) Good Standing and Power. The Domestic Borrower is duly
organized, validly existing and in good standing under the laws of the State of
Delaware.

                  (b) Corporate Authority. The Domestic Borrower has full
corporate power and authority to execute, deliver and perform this Amendment and
the Credit Agreement as hereby amended and to incur the obligations provided for
herein and therein, all of which have been duly authorized by all proper and
necessary corporate action. No consent or approval of stockholders is required
as a condition to the validity or performance or the

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exercise by the Administrative Agent of any of its rights or remedies under the
Credit Agreement as hereby amended.

                  (c) Authorizations. All authorizations, consents, approvals,
registrations, notices, exemptions and licenses with or from governmental
authorities and other persons, if any, which are necessary for the execution and
delivery of this Amendment, the performance by the Domestic Borrower of its
obligations hereunder and under the Credit Agreement as hereby amended and the
exercise by the Administrative Agent of its rights and remedies hereunder and
thereunder, have been effected or obtained and are in full force and effect.

                  (d) Binding Agreements. This Amendment and the Credit
Agreement as hereby amended constitute the valid and legally binding obligations
of the Domestic Borrower enforceable in accordance with their terms subject to
bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and
similar laws of general applicability relating to or affecting creditors rights
and to general equity principles.

                  (e) No Default. As of the date hereof, and after giving effect
to this Amendment, there does not exist any Event of Default or Incipient
Default.

                  SECTION 3. Amendments. The Domestic Borrower and the Banks
agree that effective on the Effective Date (as defined below), the definition of
the term "Letter of Credit Sublimit" in Section 1.1 is amended and restated to
read as follows:

                    "Letter of Credit Sublimit" means the least of (a) the
           aggregate Commitments, (b) Seventeen Million Dollars ($17,000,000.00)
           or (c) such lesser amount as reduced by the Borrowers pursuant to
           SECTION 2.4."

                  SECTION 4. Effectiveness. This Amendment shall become
effective on the date (the "EFFECTIVE DATE") on or prior to June 30, 2001, if
the Administrative Agent shall have received by fax or otherwise counterparts of
this Amendment signed by the Domestic Borrower, the Issuing Banks and the
Required Lenders.

                  In the event the foregoing condition precedent is not
satisfied on or before June 30, 2001, the provisions of this Amendment shall
automatically become null and void and shall have no further force or effect.

                  SECTION 5. Continuing Effectiveness. The Credit Agreement
shall remain in full force and effect in accordance with its terms except as
expressly modified by this Amendment. The Domestic Borrower agrees that this
Amendment in no way acts as a release or relinquishment of the liens or other
rights created under the Credit Agreement or any Transaction Document. Such
liens and other rights are hereby ratified and confirmed by the Domestic
Borrower in all respects.

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                  SECTION 6. Governing Law. This Amendment shall be governed by
and construed in accordance with the laws of the State of New York.

                  SECTION 7. Counterparts. This Amendment may be signed in any
number of counterparts, each of which shall be an original, with the same effect
as if the signatures thereto and hereto were upon the same instrument.

                                      -3-

<PAGE>   4



                  IN WITNESS WHEREOF, the undersigned have executed this
Amendment as of the date written above.



INTERLOGIX, INC., individually
as a Borrower and as agent for
the Borrowers


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------



PNC BANK, NATIONAL ASSOCIATION,
individually, as an Issuing
Bank and as Administrative
Agent


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------




THE BANK OF NOVA SCOTIA,
individually, as an Issuing
Bank and as
Syndication Agent


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------

                                      -4-


<PAGE>   5


FIRST UNION NATIONAL BANK,
individually and as
Documentation Agent


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------





THE CHASE MANHATTAN  BANK


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------




NATIONAL CITY BANK OF
PENNSYLVANIA


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------




SUNTRUST BANK


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------




THE BANK OF NEW YORK


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------


                                      -5-

<PAGE>   6

BANK OF AMERICA, N.A.


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------



SUMMIT BANK


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------


COMERICA BANK


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------







(WELLS FARGO BANK MINNESOTA,
N.A. (formerly know as NORWEST
BANK MINNESOTA, N.A.)


By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------


                                      -6-

<PAGE>   7


DANSKE BANK A/S

(FORMERLY KNOWN AS DEN DANSKE
BANK AKTIESELSKAB)

By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------



By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------



                                      -7-

<PAGE>   8







ERSTE BANK DER
OESTERREICHISCHEN SPARKASSEN
AG-NEW YORK

By
  -------------------------------
Name
    -----------------------------
Title
     ----------------------------





                                      -8-


<PAGE>   9



                              CONSENT AND AGREEMENT

The undersigned as of the 15th day of July, 2001 (as to itself and not any other
signatory below):

         (i) consents and agrees to the foregoing amendments to the Credit
Agreement (as amended by the foregoing, the "Amended Credit Agreement") and

         (ii) agrees that the Guaranty, dated as of May 2, 2000 of the
undersigned in favor of PNC Bank, National Association, as Administrative Agent,
remains in full force and effect after giving effect to such amendments.

SLC HOLDINGS, INC.


By:
    --------------------------------
    Name:
    Title:


CCTV CORP


By:
    --------------------------------
    Name:
    Title:


IMPAC TECHNOLOGIES


By:
    --------------------------------
    Name:
    Title:


INTERACTIVE TECHNOLOGIES, INC.


By:
    --------------------------------
    Name:
    Title:


CADDX CONTROLS, INC.


By:
    --------------------------------
    Name:
    Title:



<PAGE>   10

ITI INTERNATIONAL, INC.


By:
    --------------------------------
    Name:
    Title:


ITI FINANCE CORPORATION


By:
    --------------------------------
    Name:
    Title:


ITI DIRECT, INC.


By:
    --------------------------------
    Name:
    Title:



                                      -2-