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                                                                    Exhibit 10.2

                                 PROMISSORY NOTE

US$ 1,750,000

                                      Westwood, Massachusetts, September 5, 2002

CAR SECURITY S.A. ("Car Security"), domiciled at Avenida del Libertador 4600,
1426 Buenos Aires, Argentina, hereby promises to unconditionally pay, on or
before August 31, 2004 (or sooner, in the event of acceleration for default
hereunder or under the Loan Agreement of even date) and WITHOUT PROTEST, to
LoJack Recovery Systems Business Trust, a Massachusetts business trust and a
subsidiary of the LoJack Corporation ("LoJack"), "NO A LA ORDEN", the amount of
US$ One Million Seven Hundred Fifty Thousand ($1,750,000 U.S. dollars), plus
reasonable legal, accounting and all other reasonable transaction costs directly
incurred in connection with this Note and the transactions contemplated hereby,
or so much thereof as may from time to time be advanced and remain unpaid
hereunder. Said payment shall only be made in U.S. dollars (effective payment in
foreign currency clause, section 44, third paragraph, Decree 5965/63) to the
order of LoJack at its offices located at Westwood Executive Center, 200 Lowder
Brook Road, Suite 1000, Westwood, MA 02090.

Car Security shall also pay LoJack financing interest at an interest rate fixed
at 0.7508 percent per month, compounded monthly.

In the event that, as a consequence of foreign exchange controls, restrictions
on the transfer of foreign currency from or to the Republic of Argentina or by
reason of any other action taken by a competent governmental body, we were
prevented from making the relevant payment in the currency agreed, we shall
deliver to the legitimated holder hereof, at the latter's option: a) External
Bonds of the Republic of Argentina or any other U.S. dollar-denominated
securities issued by the National Government of any series chosen by the
legitimated holder hereof, at its sole discretion, in such number and with such
nominal value as shall suffice so that upon the sale thereof in a foreign
market, at the option of the legitimated holder hereof, the proceeds in U.S.
dollars, net of all expenses, fees and/or taxes that may be payable by reason of
its transfer or sale, shall be equal to the amount in U.S. dollars payable; or
b) the amount in legal tender then in force in the Republic of Argentina as may
be required to acquire External Bonds of the Republic of Argentina or any other
U.S. dollar-denominated securities issued by the National Government of any
series chosen by the legitimated holder hereof, at its sole discretion, in such
number and with such nominal value as shall suffice so that upon the sale
thereof in a foreign market, at the option of the legitimated holder hereof, the
proceeds in U.S. dollars, net of all expenses, fees and/or taxes that may be
payable by reason of its transfer or sale, shall be equal to the amount in U.S.
dollars payable. In either case, any of the above procedures shall only be
regarded as a discharge of obligations once the legitimated holder hereof shall
have received the entire amount of U.S. dollars due hereunder.

Car Security expressly waives its right to invoke its inability to fulfill any
payment obligation based on acts of God or force majeure events (section 514 of
the Civil Code). Car Security

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further represents that, upon executing this acknowledgement of obligations, it
is fully familiar with the current economic and financial conditions (including
the exchange rate ratio among the Argentine currency, the Euro and the U.S.
dollar set forth in law 23.928 as amended by law 25.445), having considered all
possible consequences arising from those acts and having acted with the
independent advice it has deemed convenient, for which reason it expressly
waives the right to invoke hardship ("teoria de la imprevision") as contemplated
in section 1198 of the Argentine Civil Code, the unconscionability theory and/or
any other doctrine, concept or theory already established or which may be
established in the future either by law, case law or doctrine, which may in any
way release Car Security from the full, total and timely performance of its
obligations as acknowledged hereunder.

In case of lack of payment upon presentation of this promissory note, penalty
interest shall accrue hereon at a rate equal to 1.5 times the interest rate
charged by the Banco de la Nacion Argentina (Lending Rate) for discount
transactions of 30-day negotiable instruments.

For all legal purposes arising from this Promissory Note, Car Security
establishes special domicile at Avenida del Libertador 4600, 1426 Buenos Aires,
Argentina, where all notices served shall be deemed validly given. We expressly
accept that such domicile shall be regarded as our domicile ad litem for all
judicial purposes in the terms of section 40 and related sections of the
Argentine Code of Civil and Commercial Procedure. We submit to the jurisdiction
of the Ordinary First Instance Courts hearing Commercial Matters of the City of
Buenos Aires, expressly waiving any other venue or jurisdiction.

Pursuant to the provisions of section 36 of Executive Order 5965/63, the term
for presentation of this promissory note is extended to 5 years counted as from
the issuance date hereof.

This Promissory Note is issued under the terms of Decree 5965/63 of the Republic
of Argentina.


CAR SECURITY S.A.

/s/ Carlos R. Mackinlay
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By: Carlos R. Mackinlay
Title: President