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                                                                     EXHIBIT 4.9

[CAPITAL ASSURANCE LOGO]

                                                     1221 Avenue of the Americas
                                                     New York, New York 10020
                                                     Telephone: (212) 478-3400
                                                     Facsimile: (212) 478-3597
       FINANCIAL GUARANTY
       INSURANCE POLICY

       OBLIGOR: Onyx Acceptance Owner Trust 2004-B  POLICY NO:  CA00969A

       INSURED OBLIGATION: The Class A-1 Notes,     EFFECTIVE DATE: May 27, 2004
       the Class A-2 Notes, the Class A-3 Notes
       and the Class A-4 Notes issued pursuant
       to that certain Indenture dated as of
       May 1, 2004 (the principal amount of
       which shall not exceed $450,000,000).

      XL CAPITAL ASSURANCE INC. ("XLCA"), a New York stock insurance company, in
consideration of the payment of the premium hereby unconditionally and
irrevocably guarantees to the Indenture Trustee for the benefit of the Owners of
the Insured Obligations, the full and complete payment by the Obligor of
Scheduled Payments in respect of the Insured Obligation, subject only to the
terms of this Policy (which includes the Endorsement attached hereto).

      XLCA will pay the Insured Amount to the Indenture Trustee upon the
presentation of a Payment Notice to XLCA (which Payment Notice shall include an
irrevocable assignment to XLCA of all rights and claims in respect of the
relevant Insured Obligation, as specified in the Payment Notice), on the later
of (a) one (1) Business Day following receipt by XLCA of a Payment Notice or (b)
the Business Day on which Scheduled Payments are due for payment. XLCA shall be
subrogated to the Owners' rights to payment on the Insured Obligations to the
extent of any payment by XLCA hereunder. The obligations of XLCA with respect to
a Scheduled Payment will be discharged to the extent funds to pay such Scheduled
Payment are deposited in the account specified in the Payment Notice, whether
such funds are properly applied by the Indenture Trustee or claimed by an Owner.

      In addition, in the event that any Scheduled Payment which has become Due
for Payment and which is made to an Owner by or on behalf of the Indenture
Trustee is recovered or is recoverable from the Owner pursuant to a final order
of a court of competent jurisdiction in an Insolvency Proceeding that such
payment constitutes an avoidable preference to such Owner within the meaning of
any applicable bankruptcy or insolvency law, XLCA unconditionally and
irrevocably guarantees payment of the amount of such recovery (in accordance
with Endorsement No. 1 hereto).

      This Policy sets forth in full the undertaking of XLCA and shall not be
cancelled or revoked by XLCA for any reason, including failure to receive
payment of any premium due hereunder or under the Insurance Agreement and may
not be further endorsed or modified without the written consent of XLCA and the
Indenture Trustee. The premium on this Policy is not refundable for any reason.
This Policy does not insure against loss of any prepayment or other acceleration
payment which at any time may become due in respect of any Insured Obligation,
other than at the sole option of XLCA, nor against any risk other than
Nonpayment and Avoided Payment, including any shortfalls, if any, attributable
to the liability of the Obligor for withholding taxes if any, including interest
and penalties in respect of such liability.

      THIS POLICY IS NOT COVERED BY THE PROPERTY/CASUALTY INSURANCE SECURITY
FUND SPECIFIED IN ARTICLE 76 OF THE NEW YORK INSURANCE LAW.

      Any capitalized terms not defined herein shall have the meaning given such
terms in the Endorsement attached hereto and forming a part hereof, or in the
Insurance Agreement referenced therein. In witness whereof, XLCA has caused this
Policy to be executed as of the Effective Date.

      XL CAPITAL ASSURANCE INC.

      By: /s/ Catherine R. Lau                  By: /s/ Mary Jane Constant
          ----------------------                    ----------------------------
      Name: Catherine R. Lau                    Name: Mary Jane Constant
      Title: Senior Managing Director           Title: Associate General Counsel

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                 FINANCIAL GUARANTY INSURANCE POLICY ENDORSEMENT
                           EFFECTIVE DATE MAY 27, 2004

                         ATTACHED TO AND FORMING PART OF
                FINANCIAL GUARANTY INSURANCE POLICY NO. CA00969A

Obligor:                   Onyx Acceptance Owner Trust 2004-B

Insured Obligation:        The Class A-1 Notes, the Class A-2 Notes,
                           the Class A-3 Notes and the Class A-4 Notes issued
                           pursuant to that certain Indenture, dated as of May
                           1, 2004 (the "Indenture"), between the Obligor and
                           the Indenture Trustee (the principal amount of which
                           shall not exceed $450,000,000)

Beneficiary:               JPMorgan Chase Bank as indenture trustee (the
                           "Indenture Trustee") under the Indenture

Capitalized terms used herein and not otherwise defined herein or in the Policy
shall have the meanings assigned to them in the Insurance Agreement, the Sale
and Servicing Agreement and the Indenture.

            As used herein the term "Business Day" means any day other than
Saturday or Sunday on which commercial banking institutions in New York, New
York, Los Angeles, California and in Wilmington, Delaware, are generally open
for banking business.

            As used herein the term "Insolvency Proceeding" means the
commencement, after the date hereof, of any bankruptcy, insolvency, readjustment
of debt, reorganization, marshalling of assets and liabilities or similar
proceedings by or against any Person, the commencement, after the date hereof,
of any proceedings by or against any Person for the winding up or liquidation of
its affairs, or the consent, after the date hereof, to the appointment of a
trustee, conservator, receiver or liquidator in any bankruptcy, insolvency,
readjustment of debt, reorganization, marshalling of assets and liabilities or
similar proceedings of or relating to any Person.

            As used herein the term "Insurance Agreement" means the Insurance
and Indemnity Agreement, dated as of May 27, 2004, among XLCA, the Obligor, the
Seller, the Servicer and the Indenture Trustee, as may be amended or modified
from time to time.

            As used herein the term "Insured Amount" means, that portion of the
Scheduled Payments that shall become due for payment but shall be unpaid by
reason of Nonpayment.

            As used herein the term "Nonpayment" means, with respect to any
Distribution Date, the failure of the Indenture Trustee to receive in full, in
accordance with the terms of the Indenture that Scheduled Payment that is due
for payment with respect to such date.

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            As used herein the term "Owner" means the registered owner of any
Insured Obligation as indicated in the registration books maintained by or on
behalf of the Obligor for such purpose or, if the Insured Obligation is in
bearer form, the holder of the Insured Obligation.

            As used herein, the term "Person" means any legal person, including
without limitations, an individual, a partnership, a limited liability company,
a joint venture, a corporation, a trust, an unincorporated organization, a state
banking corporation, a national banking association or a government or any
department or agency thereof.

            As used herein the term "Scheduled Payment" means (i) with respect
to any Distribution Date the amounts due and payable as the Servicing Fee to the
Servicer, and, if applicable, the Backup Servicer, including any accrued and
unpaid Servicing Fees with respect to one or more prior Collection Periods, (ii)
with respect to any Distribution Date any accrued and unpaid fees (which amounts
do not include any expenses) to the Indenture Trustee, the Owner Trustee and the
Trust Agent, (iii) with respect to any Distribution Date during the Term of this
Policy, the Note Interest Distributable Amount for each Class of Notes on such
Distribution Date and (iv) on a Note Final Scheduled Distribution Date for any
Class of Notes, the Note Principal Distributable Amount for such Class of Notes
on such Note Final Scheduled Distribution Date, in each case in accordance with
the original terms of the Insured Obligations when issued and without regard to
any subsequent amendment or modification of the Insured Obligations that has not
been consented to in writing by XLCA. Notwithstanding the foregoing, "Scheduled
Payments" shall in no event include payments which become due on an accelerated
basis as a result of (a) any default by the Obligor, (b) the occurrence of an
Event of Default under the Indenture, (c) mandatory or optional redemption, in
whole or in part, or (d) any other cause, unless XLCA elects, in its sole
discretion, to pay such amounts in whole or in part (in which event Scheduled
Payments shall include such accelerated payments at such time and to the extent
so elected by XLCA). In the event that it does not make such election, Scheduled
Payments shall include payments due in accordance with the original scheduled
terms without regard to any acceleration. In addition, "Scheduled Payment" shall
not include, nor shall coverage be provided under the Policy in respect of, (i)
any make whole, redemption or call premium payable in respect of the Insured
Obligations, (ii) any amounts due in respect of the Insured Obligations
attributable to any increase in interest rate, penalty or other sum payable by
the Issuer by reason of any default or event of default in respect of the
Insured Obligations, or by reason of any deterioration of the creditworthiness
of the Issuer or (iii) any shortfalls, if any, attributable to the liability of
the Trust for withholding taxes, if any (including interest and penalties in
respect of such liability).

            As used herein the term "Term of this Policy" means the period from
and including the Effective Date to and including the first date on which (i)
all Scheduled Payments have been paid that are required to be paid by the
Obligor under the Indenture; (ii) any period during which any Scheduled Payment
could have been avoided in whole or in part as a preference payment under
applicable bankruptcy, insolvency, receivership or similar law has expired, and
(iii) if any proceedings requisite to avoidance as a

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preference payment have been commenced prior to the occurrence of (i) and (ii)
above, a final and nonappealable order in resolution of each such proceeding has
been entered; provided, that if the Owners are required to return any Avoided
Payment (as defined below) as a result of an Insolvency Proceeding, then the
Term of this Policy shall terminate on the date on which XLCA has made all
payments required to be made under the terms of this Policy in respect of all
such Avoided Payments.

            To make a claim under the Policy, the Indenture Trustee shall
deliver to XLCA a Payment Notice in the form of Exhibit A hereto (a "Payment
Notice"), appropriately completed and executed by the Indenture Trustee. A
Payment Notice under this Policy may be presented to XLCA by (i) delivery of the
original Payment Notice to XLCA at its address set forth below, or (ii)
facsimile transmission of the original Payment Notice to XLCA at its facsimile
number set forth below. If presentation is made by facsimile transmission, the
Indenture Trustee shall (x) simultaneously confirm transmission by telephone to
XLCA at its telephone number set forth below, and (y) as soon as reasonably
practicable, deliver the original Payment Notice to XLCA at its address set
forth below. Any Payment Notice received by XLCA after 10:00 a.m., New York City
time, on a Business Day, or on any day that is not a Business Day, will be
deemed to be received by XLCA at 9:00 a.m., New York City time, on the next
succeeding Business Day. XLCA shall make payments due in respect of Insured
Amounts to the Indenture Trustee upon the presentation of a Payment Notice to
XLCA on the later of (a) one (1) Business Day following receipt by XLCA of a
Payment Notice or (b) the Business Day on which Scheduled Payments are due for
payment. XLCA shall make such payments, in the case of (a) above, no later than
2:00 p.m. New York City time and, in the case of (b) above, no later than 12:00
p.m. New York City time.

            Subject to the foregoing, if the payment of any amount with respect
to the Scheduled Payment is voided (a "Preference Event") as a result of an
Insolvency Proceeding and, as a result of such Preference Event, the Owner is
required to return such voided payment, or any portion of such voided payment,
made in respect of the Insured Obligation (an "Avoided Payment"), XLCA will pay
an amount equal to such Avoided Payment, as and when such payment would
otherwise be due pursuant to the Indenture without regard to acceleration or
prepayment, and upon receipt by XLCA from the Indenture Trustee on behalf of
such Owner of (x) a certified copy of a final order of a court exercising
jurisdiction in such Insolvency Proceeding to the effect that the Owner or the
Indenture Trustee on behalf of the Owner is required to return any such payment
or portion thereof because such payment was voided under applicable law, with
respect to which order the appeal period has expired without an appeal having
been filed (the "Final Order"), (y) an assignment, substantially in the form
attached hereto as Exhibit B, properly completed and executed by such Owner
irrevocably assigning to XLCA all rights and claims of such Owner relating to or
arising under such Avoided Payment, and (z) a Payment Notice in the form of
Exhibit A hereto appropriately completed and executed by the Indenture Trustee.

            XLCA shall make payments due in respect of Avoided Payments no later
than 2:00 p.m. New York City time on the Business Day following XLCA's receipt
of the documents required under clauses (x) through (z) of the preceding
paragraph. Any

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such documents received by XLCA after 10:00 a.m. New York City time on any
Business Day or on any day that is not a Business Day shall be deemed to have
been received by XLCA at 9:00 a.m., New York City time, on the next succeeding
Business Day. All payments made by XLCA hereunder on account of any Avoided
Payment shall be disbursed to the receiver, conservator, debtor-in-possession or
trustee in bankruptcy named in the Final Order and not to any Holder directly
(unless a Holder previously paid such amount to the receiver, conservator,
debtor-in-possession or trustee in bankruptcy named in the Final Order, in which
case such payment shall be disbursed to the Indenture Trustee for distribution
to such Holder upon proof of such payment reasonably satisfactory to XLCA).

            XLCA hereby waives and agrees not to assert any and all rights to
require the Indenture Trustee to make demand on or to proceed against any
person, party or security prior to the Indenture Trustee demanding payment under
this Policy.

            If any Payment Notice received by XLCA is not in proper form or is
otherwise insufficient for the purpose of making a claim hereunder, it shall be
deemed not to have been received by XLCA, and XLCA shall promptly so advise the
Indenture Trustee, and the Indenture Trustee may submit an amended Payment
Notice.

            Payments due hereunder unless otherwise stated herein will be
disbursed by XLCA to the Indenture Trustee on behalf of the Owners by wire
transfer of immediately available funds in the amount of such payment.

            No defenses, set-offs and counterclaims of any kind available to
XLCA so as to deny payment of any amount due in respect of this Policy will be
valid and XLCA hereby waives and agrees not to assert any and all such defenses
(including, without limitation, defense of fraud in the inducement or fact, or
any other circumstances which would have the effect of discharging a surety in
law or in equity), set-offs and counterclaims, including, without limitation,
any such rights acquired by subrogation, assignment or otherwise. Upon any
payment hereunder, in furtherance and not in limitation of XLCA's equitable
right of subrogation and XLCA's rights under the Insurance Agreement, XLCA will
be subrogated to the rights of the Owner in respect of which such payment was
made to receive any and all amounts due in respect of the obligations in respect
of which XLCA has made a payment hereunder. Any rights of subrogation acquired
by XLCA as a result of any payment made under this Policy shall, in all
respects, be subordinate and junior in right of payment to the prior
indefeasible payment in full of any amounts due the Owner on account of payments
due under the Insured Obligation.

            This Policy is neither transferable nor assignable, in whole or in
part, except to a successor trustee duly appointed and qualified under the
Indenture. All Payment Notices and other notices, presentations, transmissions,
deliveries and communications made by the Indenture Trustee to XLCA with respect
to this Policy shall specifically refer to the number of this Policy and shall
be made to XLCA at:

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                           XL Capital Assurance Inc.
                           1221 Avenue of the Americas
                           New York, New York 10020
                           Attention: Surveillance
                           Telephone: (212) 478-3400
                           Facsimile:  (212) 478- 3597

or such other address, telephone number or facsimile number as XLCA may
designate to the Indenture Trustee in writing from time to time. Each such
Payment Notice and other notice, presentation, transmission, delivery and
communication shall be effective only upon actual receipt by XLCA.

            The obligations of XLCA under this Policy are irrevocable, primary,
absolute and unconditional, subject to satisfaction of the conditions for making
a claim under the Policy, and neither the failure of any Person to perform any
covenant or obligation in favor of XLCA (or otherwise), nor the failure or
omission to make a demand permitted hereunder, nor the failure of any assignment
or grant of any security interest, nor the commencement of any Insolvency
Proceeding shall in any way affect or limit XLCA's obligations under this
Policy. If a successful action or proceeding to enforce this Policy is brought
by the Indenture Trustee, the Indenture Trustee shall be entitled to recover
from XLCA costs and expenses reasonably incurred, including, without limitation,
reasonable fees and expenses of counsel.

            This Policy and the obligations of XLCA hereunder shall terminate on
the expiration of the Term of this Policy. This Policy shall be returned to XLCA
by the Indenture Trustee upon the expiration of the Term of this Policy.

            The Property/Casualty Insurance Security Fund specified in Article
76 of the New York Insurance Law does not cover this Policy. The Florida
Insurance Guaranty Association created under Part II of Chapter 631 of the
Florida Insurance Code does not cover this Policy. In the event that XLCA were
to become insolvent, the California Insurance Guaranty Association, established
pursuant to Article 14.2 of Chapter 1 of Part 2 of Division 1 of the California
Insurance Code excludes from coverage any claims arising under this Policy.

            THIS POLICY SHALL BE CONSTRUED, AND THE OBLIGATIONS, RIGHTS AND
REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED, IN ACCORDANCE WITH THE
LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES
THAT WOULD REQUIRE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

            In the event any term or provision of the form of this Policy is
inconsistent with the provision of this Endorsement, the provision of this
Endorsement shall take precedence and be binding.

                  [Remainder of Page Intentionally Left Blank]

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            IN WITNESS WHEREOF, XL Capital Assurance Inc. has caused this
Endorsement to the Policy to be executed on the Effective Date.

By: ___________________________                 By: ____________________________
Name: Catherine R. Lau                          Name: Mary Jane Constant
Title: Senior Managing Director                 Title: Associate General Counsel

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               EXHIBIT A TO FINANCIAL GUARANTY POLICY NO. CA00969A

         XL Capital Assurance Inc.
         1221 Avenue of the Americas
         New York, New York 10020
         Attention: Surveillance

                                 PAYMENT NOTICE
                  UNDER FINANCIAL GUARANTY POLICY NO. CA00969A

            JPMorgan Chase Bank as Indenture Trustee (the "Indenture Trustee"),
hereby certifies to XL Capital Assurance Inc. ("XLCA") with reference to that
certain Financial Guaranty Policy, No. CA00969A, dated May 27, 2004 (the
"Policy"), issued by XLCA in favor of the Indenture Trustee on behalf of the
Owner under the Insurance Agreement, the Sale and Servicing Agreement and the
Indenture as follows:

            1.    The Indenture Trustee is the indenture trustee under the
Indenture and the beneficiary on behalf of each Owner of the Policy.

            2.    The Indenture Trustee is entitled to make a demand under the
Policy pursuant to Section 4.02 of the Sale and Servicing Agreement.

            3.    This notice relates to the [insert date] Distribution Date.
The amount demanded is to be paid in immediately available funds to the Payment
Account at [Identify Financial Institution Holding Account] account
number[_____].

      [For a Payment Notice in respect of Insured Amounts other than Avoided
Payment, use paragraph 4.]

            4.    The Indenture Trustee demands payment of $________ which is an
amount equal to the amount by which the [Describe calculation of Insured Amount
under Policy].

      [For a Payment Notice in respect of an Avoided Payment use the following
paragraphs [4] or [5].]

[4.] or [5.] The Indenture Trustee hereby represents and warrants, based upon
information available to it, that (i) the amount entitled to be drawn under the
Policy on the date hereof in respect of Avoided Payments is the amount paid or
to be paid simultaneously with such draw on the Policy, by the Owner on account
of a Preference Event [$________] (the "Avoided Payment Amount"), (ii) the Owner
with respect to which the drawing is being made under the Policy has paid or
simultaneously with such draw on the Policy will pay such Avoided Payment
Amount, and (iii) the documents required by the Policy to be delivered in
connection with such Avoided Payment and Avoided Payment Amount have previously
been presented to XLCA or are attached hereto.

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            [6]   The Indenture Trustee agrees that, following payment of funds
by XLCA, it shall use reasonable efforts to procure (a) that such amounts are
applied directly to the payment of any Insured Amount which is due for payment;
(b) that such funds are not applied for any other purpose; and (c) the
maintenance of accurate record of such payments in respect of the Insured
Obligation and the corresponding claim on the Policy and the proceeds thereof.

            [7]   The Indenture Trustee, on behalf of itself and the Owners,
hereby assigns to XLCA all rights and claims (including rights of actions and
claims in respect of securities laws violations or otherwise) of the Indenture
Trustee and the Owners with respect to the Insured Obligation to the extent of
any payments under the Policy. The foregoing assignment is in addition to, and
not in limitation of, rights of subrogation otherwise available to XLCA in
respect of such payments. The Indenture Trustee shall take such action and
deliver such instruments as may be reasonably required by XLCA to effectuate the
purposes of provisions [ ] of this Clause 7.

            [8]   The Indenture Trustee, on behalf of itself and the Owners,
hereby appoints XLCA as agent and attorney-in-fact for the Indenture Trustee and
the Owners in any legal proceeding in respect of the Insured Obligation. The
Indenture Trustee, on behalf of itself and the Owners, thereby (and without
limiting the generality of the preceding sentence) agrees that XLCA may at any
time during the continuation of any proceeding by or against any debtor with
respect to which a Preference Claim (as defined below) or other claim with
respect to the Insured Obligation is asserted under any Insolvency Proceeding,
direct all matters relating to such Insolvency Proceeding, including, without
limitation, (a) all matters relating to any claim in connection with a
Insolvency Proceeding seeking the avoidance as a preferential transfer of any
payment made with respect to the obligations (a "Preference Claim"), (b) the
direction of any appeal of any order relating to any Preference Claim and (c)
the posting of any surety, supersedes or performance bond pending any such
appeal. In addition, the Indenture Trustee, on behalf of itself and the Owners,
hereby agrees that XLCA shall be subrogated to, and the Indenture Trustee, on
behalf of itself and the Owners, hereby delegates and assigns, to the fullest
extent permitted by law, the rights of the Indenture Trustee and the Owners in
the conduct of any Insolvency Proceeding, including, without limitation, all
rights of any party to an adversary proceeding or action with respect to any
court order issued in connection with any such Insolvency Proceeding.

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            Capitalized terms used herein and not otherwise defined herein shall
have the meanings assigned to them in the Policy or [Identify Document]

            IN WITNESS WHEREOF, this notice has been executed this ____ day of
________, ____.

                                         _________________, as Indenture Trustee

                                                 By:____________________________
                                                    Authorized Officer

Any Person Who Knowingly And With Intent To Defraud Any Insurance Company Or
Other Person Files An Application For Insurance Or Statement Of Claim Containing
Any Materially False Information, Or Conceals For The Purpose Of Misleading
Information Concerning Any Fact Material Thereof, Commits A Fraudulent Insurance
Act, Which Is A Crime, And Shall Also Be Subject To A Civil Penalty Not To
Exceed Five Thousand Dollars And The Stated Value Of The Claim For Each Such
Violation

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         EXHIBIT B TO FINANCIAL GUARANTY INSURANCE POLICY, NO. CA00969A

      FORM OF ASSIGNMENT

      Reference is made to the Financial Guaranty Insurance Policy No. CA00969A,
dated May 27, 2004 (together with the Endorsement attached thereto, the
"Policy") issued by XL Capital Assurance Inc. ("XLCA") relating to the [Identify
Insured Obligation]. Unless otherwise defined herein, capitalized terms used in
this Assignment shall have the meanings assigned thereto in the Policy as
incorporated by reference therein. In connection with the Avoided Payment of [$
] paid by the undersigned (the "Owner") on [ ] and the payment by XLCA in
respect of such Avoided Payment pursuant to the Policy, the Owner hereby
irrevocably and unconditionally, without recourse, representation or warranty
(except as provided below), sells, assigns, transfers, conveys and delivers all
of such Owner's rights, title and interest in and to any rights or claims,
whether accrued, contingent or otherwise, which the Owner now has or may
hereafter acquire, against any person relating to, arising out of or in
connection with such Avoided Payment. The Owner represents and warrants that
such claims and rights are free and clear of any lien or encumbrance created or
incurred by such Owner.(1)

                                                         _______________________
                                                         Owner

--------
            (1) In the event that the terms of this form of assignment are
reasonably determined to be insufficient solely as a result of a change of law
or applicable rules after the date of the Policy to fully vest all of the
Owner's right, title and interest in such rights and claims, the Owner and XLCA
shall agree on such other form as is reasonably necessary to effect such
assignment, which assignment shall be without recourse, representation or
warranty except as provided above.

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