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                                                                     EXHIBIT 4.8



                      FOURTH AMENDMENT TO CREDIT AGREEMENT


         THIS FOURTH AMENDMENT TO CREDIT AGREEMENT, dated as of February 8, 2001
(this "Amendment"), is by and between PERCEPTRON, INC., a Michigan corporation
(the "Borrower"), and BANK ONE, MICHIGAN, a Michigan banking corporation (the
"Bank").

                                    RECITALS

         A. The Borrower and the Bank have entered into the Credit Agreement,
dated May 28, 1999, as amended by First Amendment to Credit Agreement dated as
of August 24, 1999, Second Amendment to Credit Agreement dated as of June 30,
2000, and Third Amendment to Credit Agreement dated as of November 9, 2000 (the
"Credit Agreement"), pursuant to which the Bank provides to the Borrower a
revolving credit facility, including letters of credit, in the aggregate
principal amount not to exceed $15,000,000.

         B. The Borrower now desires that the Credit Agreement be amended in
order to extend the termination date of the revolving credit facility and modify
certain financial covenants of the Borrower thereunder, and the Bank is willing
to so amend the Credit Agreement on the terms and conditions herein set forth.

         NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein and in the Credit Agreement contained, the parties hereto
agree as follows:


                    ARTICLE 1. AMENDMENTS TO CREDIT AGREEMENT

         Retroactively effective as of December 31, 2000, the Credit Agreement
hereby is amended as follows:

         1.1 Subparagraph "(vi)" of Section 6.1 (relabeled as such pursuant to
the Second Amendment referenced above) is further relabeled as subparagraph
("vii)", and new subparagraph "(vi)" is added to Section 6.1, as follows:

                  (vi) As soon as available and in any event within 15 calendar
                  days after the end of each calendar month, a report of the
                  Borrower's domestic accounts receivable, including without
                  limitation the amount, age and account debtor for each
                  domestic account receivable, and otherwise in form and detail
                  satisfactory to the Bank.

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         1.2 Sections 6.12, 6.13, 6.14 and 6.19 (which was added pursuant to the
First Amendment referenced above) are amended and restated in full as follows:

                  6.12 FUNDED DEBT TO EBITDA RATIO. The Borrower will not permit
                  or suffer the ratio of (i) the Funded Debt of the Borrower as
                  of the fiscal quarter end corresponding to the determination
                  date to (ii) the EBITDA of the Borrower for the period of four
                  consecutive fiscal quarters of the Borrower then ending to
                  exceed (A) 6.75 to 1.00 as of September 30, 2001, December 31,
                  2001 and March 31, 2002, and (B) 4.75 to 1.00 as of June 30,
                  2002 and each subsequent fiscal quarter end of the Borrower.

                  6.13 EBITDA. The Borrower will not permit its EBITDA to be
                  less than (i) ($2,600,000) for the period from July 1, 2000
                  through the end of its fiscal quarter ending on or about
                  December 31, 2000, (ii) ($4,400,000) for the period from July
                  1, 2000 through the end of its fiscal quarter ending on or
                  about March 31, 2001, (iii) ($1,900,000) for the period from
                  July 1, 2000 through the end of its fiscal quarter ending on
                  or about June 30, 2001, (iv) $300,000 for the period from July
                  1, 2001 through the end of its fiscal quarter ending on or
                  about September 30, 2001, (v) $1,000,000 for the period from
                  July 1, 2001 through the end of its fiscal quarter ending on
                  or about December 31, 2001, (vi) $800,000 for the period from
                  July 1, 2001 through the end of its fiscal quarter ending on
                  or about March 31, 2002, and (vii) $3,100,000 for the period
                  from July 1, 2001 through the end of its fiscal quarter ending
                  on or about June 30, 2002.

                  6.14 FIXED CHARGE COVERAGE RATIO. The Borrower will not permit
                  its Fixed Charge Coverage Ratio to be less than 1.50 to 1.00
                  as of the fiscal quarter end of the Borrower corresponding to
                  September 30, 2001 and as of each subsequent fiscal quarter
                  end of the Borrower; such ratio to be determined as of each
                  fiscal quarter end of the Borrower (commencing with the fiscal
                  quarter end corresponding to September 30, 2001) for the
                  period of four consecutive fiscal quarters of the Borrower
                  then ending.

                                           * * *

                  6.19 TOTAL LIABILITIES TO TANGIBLE NET WORTH RATIO. The
                  Borrower will not permit the ratio of Total Liabilities to
                  Tangible Net Worth to exceed 0.75 to 1.00 at any time.



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                     [FOURTH AMENDMENT TO CREDIT AGREEMENT]

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                         ARTICLE 2. CONDITIONS PRECEDENT

         As conditions precedent to the effectiveness of the amendments to the
Credit Agreement set forth in Article 1 of this Amendment, the Bank shall
receive this Amendment duly executed on behalf of the Borrower, along with a fee
for this Amendment in the amount of $10,000 in immediately available funds.


                    ARTICLE 3. REPRESENTATIONS AND WARRANTIES

         In order to induce the Bank to enter into this Amendment, the Borrower
represents and warrants that:

         3.1 The execution, delivery and performance by the Borrower of this
Amendment are within its corporate powers, have been duly authorized by all
necessary corporate action and are not in contravention of any law, rule or
regulation, or any judgment, decree, writ, injunction, order or award of any
arbitrator, court or governmental authority, or of the terms of the Borrower's
charter or by-laws, or of any contract or undertaking to which the Borrower is a
party or by which the Borrower or its property is or may be bound or affected.

         3.2 This Amendment is a legal, valid and binding obligation of the
Borrower, enforceable against the Borrower in accordance with its terms.

         3.3 No consent, approval or authorization of or declaration,
registration or filing with any governmental authority or any nongovernmental
person or entity, including without limitation any creditor or stockholder of
the Borrower, is required on the part of the Borrower in connection with the
execution, delivery and performance of this Amendment or the transactions
contemplated hereby or as a condition to the legality, validity or
enforceability of this Amendment.

         3.4 After giving effect to the amendments contained in Article 1 of
this Amendment, the representations and warranties contained in Article 5 of the
Credit Agreement are true on and as of the date hereof with the same force and
effect as if made on and as of the date hereof.

         3.5 No Default or Unmatured Default has occurred and is continuing.


                            ARTICLE 4. MISCELLANEOUS

         4.1 If the Borrower shall fail to perform or observe any term, covenant
or agreement in this Amendment, or any representation or warranty made by the
Borrower in this Amendment shall prove to have been incorrect in any material
respect when made, such occurrence shall be deemed to constitute a Default.


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                     [FOURTH AMENDMENT TO CREDIT AGREEMENT]


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         4.2 All references to the Credit Agreement in any other document,
instrument or certificate referred to in the Credit Agreement or delivered in
connection therewith or pursuant thereto, hereafter shall be deemed references
to the Credit Agreement, as amended hereby.

         4.3 All promissory notes, security documents and other agreements,
instruments, certificates and other documents delivered in connection with the
Credit Agreement, and, subject to the amendments herein provided, the Credit
Agreement, are hereby ratified and confirmed, and shall in all respects continue
in full force and effect, notwithstanding that any of such documents may have
been executed by only one officer of the Borrower.

         4.4 Capitalized terms used but not defined herein shall have the
respective meanings ascribed thereto in the Credit Agreement.

         4.5 This Amendment shall be governed by and construed in accordance
with the laws of the State of Michigan.

         4.6 The Borrower agrees to pay the reasonable fees and expenses of
Dickinson Wright PLLC, counsel for the Bank, in connection with the negotiation
and preparation of this Amendment and the documents referred to herein and the
consummation of the transactions contemplated hereby, and in connection with
advising the Bank as to its rights and responsibilities with respect thereto.

         4.7 This Amendment may be executed upon any number of counterparts with
the same effect as if the signatures thereto were upon the same instrument.

                [The rest of this page intentionally left blank.]



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                     [FOURTH AMENDMENT TO CREDIT AGREEMENT]


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered as of the day and year first-above written.


                                         PERCEPTRON, INC.


                                         By: /S/ John J. Garber
                                             -----------------------------------
                                             John Garber
                                             Its: Chief Financial Officer


                                         By: /S/ Sylvia M. Smith
                                             -----------------------------------
                                             Sylvia M. Smith
                                             Its:  Controller


                                         BANK ONE, MICHIGAN
                                         (formerly known as NBD Bank)


                                         By: /S/ Donna Boris
                                             -----------------------------------
                                             Donna Boris
                                             Its: Vice President



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