<PAGE>   1

                                    FORM 10-Q

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

(Mark One)

[X]  QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES AND
     EXCHANGE ACT OF 1934.

     For the quarterly period ended March 31, 1999.

                                       or

[ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934.

                  For the transition period from         to            .
                                                 -------    -----------


                         Commission File Number: 016441
                                                 ------


                               CODE - ALARM, INC.
                               ------------------
             (Exact name of registrant as specified in its charter)

                                    MICHIGAN
                                    --------
                         (State or other jurisdiction of
                         incorporation or organization)


                                   38-2334698
                                   ----------
                                (I.R.S. Employer
                               Identification No.)

          950   EAST WHITCOMB, MADISON HEIGHTS, MICHIGAN        48071

          --------------------------------------------------------------
        (Address of principal executive offices)              (Zip Code)

       (Registrant's telephone number, including area code): 248-583-9620
                                                             ------------

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.


     Yes  X             No
         ---                ---

     The number of shares outstanding of the registrants common stock, without
par value, as of May 28, 1999 is 2,320,861.



<PAGE>   2



                                      INDEX

<TABLE>
<CAPTION>


                                                                                            Page No.
                                                                                           --------
<S>                                                                                        <C>
Part I. - Financial Information

        Condensed Consolidated Balance Sheets
              As of March 31, 1999 (Unaudited) and December 31, 1998                           3

        Condensed Consolidated Statements of Operations (Unaudited) -
              Three months ended March 31, 1999 and 1998                                       4

        Condensed Consolidated Statements of Cash Flows (Unaudited) -
               Three months ended March 31, 1999 and 1998                                      5

        Notes to Condensed Consolidated Financial Statements                                   6

        Management's Discussion and Analysis of Financial
              Condition and Results of Operations                                              7



Part II.  -  Other Information                                                                 8
</TABLE>



                                       2


<PAGE>   3
                         PART I. - FINANCIAL INFORMATION

ITEM 1.    FINANCIAL STATEMENTS


                                CODE-ALARM, INC.
                     CONDENSED CONSOLIDATED BALANCE SHEETS
                                 (IN THOUSANDS)

<TABLE>
<CAPTION>

                                                                            March 31,
                                                                               1999            December 31,
ASSETS                                                                     (Unaudited)            1998
                                                                         ---------------   ----------------


<S>                                                                          <C>                 <C>
Cash                                                                         $    753            $     62
Accounts receivable, less allowance of $555 and $486 as of
    March 31, 1999 and December 31, 1998, respectively                          4,514               3,793
Inventories                                                                     2,575               2,727
Other                                                                             340                 474
                                                                             --------            --------
             Total current assets                                               8,182               7,056

Property and equipment, net of accumulated depreciation                         1,817               1,908

Other assets, net of amortization:
    Goodwill                                                                      287                 293
    Other intangibles                                                              92                 105
    Financing costs                                                             2,552               2,802
    Other                                                                         181                 187
                                                                             --------            --------
             Total assets                                                    $ 13,111            $ 12,351
                                                                             ========            ========

LIABILITIES AND SHAREHOLDERS' EQUITY (DEFICIT)

Accounts payable                                                             $  3,806            $  4,176
Accrued expenses                                                                2,224               1,775
Current portion of long-term debt                                                 416                 451
                                                                             --------            --------
             Total current liabilities                                          6,446               6,402

Long-term debt                                                                 20,084              18,006

Commitments and contingencies (Note 4)

Series A 10% redeemable preferred stock                                         7,351               7,351

Shareholders' equity (deficit):
    Preferred stock
    Series B redeemable preferred stock
    Common stock                                                               12,213              12,213
    Other equity                                                                7,179               7,179
    Accumulated deficit                                                       (40,162)            (38,800)
                                                                             --------            --------
             Total shareholders' equity (deficit)                             (20,770)            (19,408)
                                                                             --------            --------
             Total liabilities and shareholders' equity (deficit)            $ 13,111            $ 12,351
                                                                             ========            ========
</TABLE>


See accompanying notes to condensed consolidated financial statements.

                                        3
<PAGE>   4


                                CODE-ALARM, INC.
                CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
                                  (UNAUDITED)
                   (IN THOUSANDS, EXCEPT FOR PER SHARE DATA)
<TABLE>
<CAPTION>

                                                                      Three Months Ended
                                                                          March 31
                                                                   -------------------------
                                                                   1999               1998
                                                                   ----               ----
<S>                                                               <C>                <C>
Net sales                                                         $ 8,362            $13,826
Cost of sales                                                       5,429              8,816
                                                                  -------            -------
Gross profit                                                        2,933              5,010
Operating expenses:
      Sales and marketing                                           1,809              1,836
      Engineering                                                     465                396
      General and administrative                                    1,028              1,496
                                                                  -------            -------
                                                                    3,302              3,728
                                                                  -------            -------
Income (loss) from operations                                        (369)             1,282
Other expense:
      Interest expense                                                424                347
      Amortization of financing costs                                 385                206
      Other                                                                               79
                                                                  -------            -------
                                                                      809                632
                                                                  -------            -------
Income (loss) before income taxes                                  (1,178)               650
Income taxes
                                                                  -------            -------
Net income (loss)                                                  (1,178)               650
Preferred stock dividends                                             184                175
                                                                  -------            -------
Net income (loss) applicable to common stock                      $(1,362)           $   475
                                                                  =======            =======
Basic earnings (loss) per share                                   $ (0.59)           $  0.20
                                                                  =======            =======
Weighted average common shares outstanding                          2,321              2,321
                                                                  =======            =======
Diluted earnings (loss) per share                                 $ (0.59)           $  0.14
                                                                  =======            =======
Weighted average common and dilutive shares outstanding             2,321              3,493
                                                                  =======            =======
</TABLE>



See accompanying notes to condensed consolidated financial statements.

                                       4
<PAGE>   5
                                CODE-ALARM, INC.
                CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                                  (UNAUDITED)
                                 (IN THOUSANDS)
<TABLE>
<CAPTION>


                                                                         Three Months Ended March 31
                                                                       ------------------------------
                                                                          1999               1998
                                                                          ----               ----

<S>                                                                     <C>                <C>
Cash flows from operating activities                                    $(1,143)           $   777

Cash flows from investing activities:
     Capital expenditures                                                   (74)              (251)

Cash flows from financing activities:
     Net advances (payments) on credit agreements                         2,078                (46)
     Payments on term notes and capitalized lease obligations               (35)              (476)
     Financing issue costs                                                 (135)
                                                                        -------            -------

Net increase in cash                                                        691                480

Cash, beginning of period                                                    62                 36
                                                                        -------            -------

Cash, end of period                                                     $   753            $   516
                                                                        =======            =======


Supplemental disclosures of cash flow information:
     Cash paid during the three month period for interest               $   245            $   256
                                                                        =======            =======
</TABLE>



See accompanying notes to condensed consolidated financial statements.


                                       5
<PAGE>   6
                                 CODE-ALARM, INC
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

1.   The unaudited condensed consolidated financial statements have been
     prepared on the same basis as the audited condensed consolidated financial
     statements and, in the opinion of management, reflect all adjustments
     (consisting of normal recurring adjustments) necessary for a fair
     presentation for each of the periods presented. The results of operations
     for the interim periods are not necessarily indicative of results to be
     expected for the fiscal years.

     The accompanying condensed consolidated financial statements and related
     footnotes have been prepared in accordance with instructions under Rule
     10-01 of Regulation S-X and do not contain all information for complete
     financial statements. For further information, refer to the consolidated
     financial statements and related footnotes for the year ended December 31,
     1998 included in the Company's Annual Report on Form 10-K.

     On January 1, 1998, the Company adopted Financial Accounting Standards
     Board Statement No. 130, "Reporting Comprehensive Income." During the
     interim periods presented, the Company had no elements of comprehensive
     income, other than net loss. Accordingly, a Statement of Comprehensive
     Income has not been provided as comprehensive income (loss) equals net
     income (loss) for the interim periods presented.

2.   The financial statements include the accounts of the Company and its wholly
     owned subsidiaries. All significant intercompany accounts and transactions
     have been eliminated.

3.   Inventories consist of the following:

<TABLE>
<CAPTION>

                           March 31, 1999      December 31
                            (Unaudited)            1998
                           --------------     --------------
                                   (In thousands)
<S>                           <C>                 <C>
    Raw materials             $1,980              $2,234
    Work in process              394                 310
    Finished goods               201                 183
                              ------              ------
                              $2,575              $2,727
                              ======              ======
</TABLE>


4.   In 1995, the Company was named as a defendant in an action filed in August
     1990 in the United States District Court for Puerto Rico to enforce a
     patent infringement default judgment rendered against certain predecessors
     in title to assets now owned by the Company which were purchased by the
     Company from a bank in Illinois in January 1990. The amount of the judgment
     was $19.4 million, which with accumulated interest had reached
     approximately $30 million. The Puerto Rico court dismissed the action and
     held that any action to collect from the Company and its subsidiary as
     successors in interest to the judgment debtor must be raised before the
     Illinois court. On March 20, 1997, the case was refiled by the judgment
     creditors in Illinois. The bank is providing for up to 50% of the defense
     of the Company subject to reservation of rights against the Company. The
     Company, through its counsel, filed a Motion to Dismiss, which resulted in
     a limitation of the claims the plaintiffs could pursue. After the close of
     discovery, the Company filed a Motion for Summary Judgment, on which the
     court has not yet ruled. While the Company believes that it has meritorious
     defenses to the claims asserted in this lawsuit, the ultimate outcome of
     this lawsuit cannot be determined at this time, and the Company is unable
     to estimate the range of possible loss, if any.

     In March 1999, the Company was named as a defendant in a motion to reopen a
     case enforcing terms of a settlement agreement, granting partial summary
     judgment. The motion alleged that the plaintiff is entitled to at least
     $1.3 million, and asked for a partial judgment in that amount, attorney
     fees and costs, and the production of certain documents. The Company
     intends to vigorously defend the motion, but there can be no assurance that
     the Company will prevail or of the amount of damages to which it may be
     subject if it does not prevail.

     Various other legal actions and claims are pending or could be asserted
     against the Company. Litigation is subject to many uncertainties; the
     outcome of individual litigation matters is not predictable with assurance,
     and it is reasonably possible that some of these matters may be decided
     unfavorably to the Company. Based on information currently available and
     established reserves, it is the opinion of management that the ultimate
     liability, if any, with respect to these matters will not materially affect
     the financial position, and the results of operations of the Company.

5.   As reported in the Company's 1998 Annual Report on Form 10-K, on March 29,
     1999, the Company entered into agreements amending the warrants previously
     issued by the Company to the holders of its Series A-1 Preferred Stock and
     senior lender.  The agreements provide, among other things, for a reduction
     in exercise price of certain warrants from a $1.04 and $1.88 to $.52 per
     share.  The Company is currently  reviewing the appropriate valuation and
     accounting treatment of the reduction in warrant exercise price, and
     expects to determine and record any necessary amount by the end of the
     quarter ending June 30, 1999.


                                       6
<PAGE>   7


ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
         RESULTS OF OPERATIONS.


Results of Operations

     The Company's sales were down $5.5 million, or 39.5%, to $8.4 million for
     the three months ended March 31, 1999, as compared to $13.8 million for the
     three months ended March 31, 1998. Quarter to quarter sales to
     international distributors in several of the Company's key overseas
     markets, GM dealer sales, port-of-entry, and expediter sales all decreased,
     contributing to the decline. The Company anticipates that near term sales
     will approximate the first quarter 1999 levels.

     For the three months ended March 31, 1999, consolidated gross profit
     decreased $2.1 million, or 41.5%, to $2.9 million as compared to $5 million
     for the three month period ended March 31, 1998. Gross profit as a
     percentage of consolidated net sales decreased to 35.1% for the period
     ended March 31, 1999, from 36.2% for the comparable period in 1998.
     Although lower volumes had an adverse impact on the gross profit
     percentage, the Company was able to partially offset the gross profit
     percent decrease with reduced product costs.

     Consolidated operating expenses for the first three months of 1999
     decreased $426,000, or 11.4%, to $3.3 million as compared to $3.7 million
     for the first three months of 1998. The decrease was due to lower general
     and administrative expenses, resulting from cost reduction efforts and
     lower reserves for trade receivable allowances.

     As a result, the Company reported an operating loss for the three months
     ended March 31, 1999, of $369,000 as compared to operating income of
     $1,282,000 for the comparable period in 1998.

     Interest expense was up 22.2% for the three months ended March 31, 1999, as
     compared to the three month period ended March 31, 1998. The increase was
     primarily due to additional borrowings, offset by lower average interest
     rates during the current period.

     The Company has determined that any income tax benefit, and related asset,
     resulting from current and prior period operating losses is not currently
     recognizable, and therefore no related amounts have been recorded for the
     three month periods ended March 31, 1999 and 1998.

     As a result of the foregoing, the Company recorded a net loss for the three
     months ended March 31, 1999, of $1,178,000, compared to net income of
     $650,000 for the three months ended March 31, 1998.

Liquidity and Capital Resources

     The Company's consolidated working capital was $1,736,000 at March 31, 1999
     as compared to $654,000 at December 31, 1998. In addition, the current
     ratio (current assets divided by current liabilities) was 1.27 to 1 at
     March 31, 1999, as compared to 1.10 to 1 at December 31, 1998. The increase
     in working capital and current ratio as of March 31, 1999, as compared to
     December 31, 1998, was due to proceeds received on March 31, 1999, from the
     new credit agreement and higher end of period sales.

     The Company's net loss for the quarter ended March 31, 1999, and increased
     working capital requirements were financed with additional borrowings. As
     of March 31, 1999, the Company had outstanding $8.1 million on its $12
     million revolving credit line, and $1 million on the $1.5 million credit
     agreement. As of March 31, 1999, the Company had $753,000 in cash on hand,
     and $846,000 available for borrowing under these facilities.

Year 2000 Readiness Disclosure

     The "Year 2000 issue" is generally used to describe various problems that
     may result from the improper processing of dates related to the year 2000
     and beyond by computers and other types of equipment, including embedded
     technology in production machinery and equipment, due to some systems
     storing the year as two digits versus four digits. This generally means
     that affected computer hardware and software will not properly distinguish
     dates in 2000 from dates in 1900.

     See the Company's Annual Report on Form 10-K as filed on May 20, 1999, for
     a current discussion on this matter.




                                       7

<PAGE>   8



                          PART II. - OTHER INFORMATION




ITEM 6.        EXHIBITS AND REPORTS ON FORM 8-K.

(a)               Exhibits

Exhibit
Number            Description


10.1.9   Amendment No. 5 and Waiver No. 8 to Credit Agreement dated as of March
         29, 1999, by and among the Company, the other Credit Parties from time
         to time party to the Credit Agreement, General Electric Capital
         Corporation ("GECC") in its capacity and the other financial
         institutions from time to time party to the Credit Agreement (the
         "Lenders"), and GECC in its separate capacity as agent for the Lenders.

10.42    Credit Agreement dated as of March 29, 1999 among the Company, Pegasus
         Partners, L.P., Pegasus Related Partners, L.P., and General Electric
         Capital Corporation.

10.43    Amendment Agreement dated as of March 29, 1999 between the Company and
         General Electric Capital Corporation.

10.44    Amendment Agreement dated as of March 29, 1999 among the Company and
         Pegasus Partners, L.P. and Pegasus Related Partners, L.P.

11       Statement regarding Computation of Per Share Earnings.

27       Financial Data Schedule.


(b)      During the quarter ended March 31, 1999, there were no reports on Form
         8-K filed.


                                       8
<PAGE>   9




                                   SIGNATURES


     Pursuant to the requirements of the Securities Exchange Act of 1934, the
     Registrant has duly caused this report to be signed on its behalf by the
     undersigned thereunto duly authorized.


                                                     CODE-ALARM, INC.
                                                     ----------------
                                                        (Registrant)


Date:    May 28, 1999                                /s/  Rand W. Mueller
         ------------                                --------------------
                                                     Rand W. Mueller
                                                     President, Chief
                                                     Executive Officer
                                                     And Director


Date:    May 28, 1999                                /s/  Craig S. Camalo
         ------------                                --------------------
                                                     Craig S. Camalo
                                                     Vice President of
                                                     Finance, Chief
                                                     Financial Officer







                                       9
<PAGE>   10


                                  EXHIBIT INDEX




10.1.9   Amendment No. 5 and Waiver No. 8 to Credit Agreement dated as of March
         29, 1999, by and among the Company, the other Credit Parties from time
         to time party to the Credit Agreement, General Electric Capital
         Corporation ("GECC") in its capacity and the other financial
         institutions from time to time party to the Credit Agreement (the
         "Lenders"), and GECC in its separate capacity as agent for the Lenders.

10.42    Credit Agreement dated as of March 29, 1999 among the Company, Pegasus
         Partners, L.P., Pegasus Related Partners, L.P., and General Electric
         Capital Corporation.

10.43    Amendment Agreement dated as of March 29, 1999 between the Company and
         General Electric Capital Corporation.

10.44    Amendment Agreement dated as of March 29, 1999 among the Company and
         Pegasus Partners, L.P. and Pegasus Related Partners, L.P.

11       Statement regarding Computation of Per Share Earnings.

27       Financial Data Schedule.