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                                                                    EXHIBIT 4.15


                                 AMENDMENT NO. 1


                                       to

                          SALE AND SERVICING AGREEMENT


                                     between

                       ONYX ACCEPTANCE OWNER TRUST 2003-B
                                   as Issuer,


                      ONYX ACCEPTANCE FINANCIAL CORPORATION
                                   as Seller,


                           ONYX ACCEPTANCE CORPORATION
                                  as Servicer,


                                       and

                                 CITIBANK, N.A.
                      as Indenture Trustee and Trust Agent

                                -----------------


                          Dated as of November 14, 2003
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         This Amendment No. 1 to Sale and Servicing Agreement between Onyx
Acceptance Owner Trust 2003-B, as Issuer, Onyx Acceptance Financial Corporation,
as Seller, Onyx Acceptance Corporation, as Servicer, and Citibank, N.A., as
Indenture Trustee and Trust Agent (this "Amendment") is dated and effective as
of November 14, 2003.

         WHEREAS, the parties hereto entered into the Sale and Servicing
Agreement, dated as of May 1, 2003 (the "Sale and Servicing Agreement");

         WHEREAS, the parties hereto desire to modify certain provisions of the
Sale and Servicing Agreement relating to the rights and obligations of the
Back-up Servicer;

         WHEREAS, Section 9.01 of the Sale and Servicing Agreement permits the
amendments contemplated herein by the Issuer, the Seller, the Servicer, the
Indenture Trustee and the Trust Agent without the consent of any Noteholders,
provided the Rating Agency Condition is satisfied and the consent of the Insurer
is obtained;

         WHEREAS, the parties hereto have notified the Rating Agencies and have
confirmed that the Rating Agency Condition has been satisfied with respect to
this Amendment;

         WHEREAS, the parties hereto wish to amend the Sale and Servicing
Agreement;

         NOW, THEREFORE, the parties hereto agree that the Sale and Servicing
Agreement is hereby amended as follows:

         SECTION 1. EFFECTIVE DATE. This Amendment shall be effective as of
November 14, 2003.

         SECTION 2.  DEFINITIONS.

         (a) Capitalized Terms. For purposes of this Amendment, all capitalized
terms used and not otherwise defined herein have the meanings set forth in the
Sale and Servicing Agreement.

         (b) Amendment of Section 1.01. The following defined term is hereby
amended and restated in its entirety as follows:

                  "SERVICER" means Onyx in its capacity as the servicer of the
         Contracts under Section 3.01, and, in each case upon succession in
         accordance herewith, each Successor Servicer; provided, however, that
         the Back-up Servicer, if appointed Successor Servicer, shall succeed
         only to those responsibilities, duties and liabilities of the Servicer
         described hereunder as may be set forth in or modified by the Back-up
         Servicing Agreement.

         SECTION 3. TRUSTEE TO ACT; APPOINTMENT OF SUCCESSOR. The first
paragraph of Section 7.02 is hereby amended and restated in its entirety as
follows:

                  Except as otherwise provided in this Section 7.02, upon the
         termination or resignation of the Servicer, the Insurer shall appoint


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         a successor servicer (the "Successor Servicer"), which Successor
         Servicer shall succeed to all the responsibilities, duties and
         liabilities of the Servicer hereunder other than the obligation of the
         Servicer to purchase Contracts pursuant to Section 3.07 of this
         Agreement. If the Insurer fails to appoint a Successor Servicer within
         ten (10) Business Days of the termination or resignation of the
         Servicer, the Back-up Servicer, if any, shall become the Successor
         Servicer pursuant to the terms of the Back-up Servicing Agreement. In
         such case, the Back-up Servicer shall assume the servicing obligations
         and duties of the Servicer in accordance with Section 2.1(b) of the
         Back-up Servicing Agreement but shall not be obligated to purchase
         Contracts pursuant to Section 3.07 of this Agreement. Upon its
         appointment as Successor Servicer, any Successor Servicer appointed
         pursuant to the provisions of this Section 7.02, other than the Back-up
         Servicer, shall be entitled to that portion of the Servicing Fee
         payable to the Servicer and such other compensation (whether payable
         out of the Collection Account or otherwise) as the Servicer would be
         entitled to under this Agreement. The Back-up Servicer shall be
         entitled to such compensation specified in the Back-Up Servicing
         Agreement.

         SECTION 4. GOVERNING LAW. THIS AGREEMENT SHALL BE CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA AND THE OBLIGATIONS, RIGHTS,
AND REMEDIES OF THE PARTIES UNDER THE AGREEMENT SHALL BE DETERMINED IN
ACCORDANCE WITH SUCH LAWS, EXCEPT THAT THE DUTIES OF THE TRUST AGENT AND THE
INDENTURE TRUSTEE SHALL BE GOVERNED BY THE LAWS OF THE STATE OF NEW YORK.

         SECTION 5. COUNTERPARTS. This Amendment may be executed in several
counterparts, each of which shall be an original and all of which shall
constitute but one and the same instrument.

         SECTION 6. INSURER INSTRUCTION TO OWNER TRUSTEE. By its consent hereto,
the Insurer hereby confirms that no Insurer Default has occurred and is
continuing and authorizes and instructs the Owner Trustee to execute and deliver
this Amendment, on behalf of the Issuer.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 1
to Sale and Servicing Agreement to be duly executed and delivered as of the day
and year first above written.


                             ONYX ACCEPTANCE OWNER TRUST 2003-B
                             as Issuer

                             By:  Chase Manhattan Bank USA, National
                                  Association, not in its individual capacity
                                  but solely as Owner Trustee


                                  By:___________________________________________
                                  Name:_________________________________________
                                  Title:________________________________________


                             ONYX ACCEPTANCE FINANCIAL
                             CORPORATION, as Seller

                             By:________________________________________________
                                Michael A. Krahelski
                                Senior Vice President


                             ONYX ACCEPTANCE CORPORATION, as
                             Servicer and Custodian


                             By:________________________________________________
                                Don P. Duffy
                                Executive Vice President and
                                Chief Financial Officer


                             CITIBANK, N.A., not in its individual capacity but
                             solely as Indenture Trustee and as Trust Agent


                             By:________________________________________________
                             Name:______________________________________________
                             Title:_____________________________________________


Amendment No. 1 to Sale and Servicing Agreement (2003-B) - Signature Page
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Consented to:

MBIA INSURANCE CORPORATION


By:
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Name:
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Title:
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