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Legal & Dispute Support

Independent
Expert Witness

CPR Part 35 compliant expert technical reports for vehicle disputes. Small claims, Financial Ombudsman Service, and county court proceedings. Reports produced by a practising automotive diagnostic specialist with 28 years of professional experience.

CPR Part 35 Compliant
VAT Registered · GB286590361
Motor Trade Insurance Held
RMI Academy Trained
FOS & Small Claims Accepted
Qualifications & Standing

Who I Am

Jeremy Vinnicombe, sole principal of Autodiag. 28 years of professional automotive diagnostic experience across independent workshop, fleet, and specialist environments. Manufacturer-level system access across all major brands. RMI Academy of Automotive Skills trained. Fully VAT-registered sole trader with motor trade, public liability, and employers liability insurance.

Reports are prepared in the name of Autodiag, referenced as AUTOD-EXPR-[YEAR]-[NUMBER], and carry a signed CPR Part 35 statement of truth. My overriding duty is to the court, not to the instructing party.

Independent & Impartial

My duty under CPR Part 35 is to the court. Opinions are based solely on documented evidence and professional expertise. If the evidence does not support a claim, I will say so before a report is commissioned.

Court-Ready Reports

Every report includes a compliance statement, declaration of instructions, full list of documents considered, qualified technical opinions, acknowledged limitations, and a signed statement of truth. Ready for direct submission.

Areas of Expertise

Scope of Work

All reports are based on documentary evidence including workshop inspection reports, fault code records, manufacturer technical data, and case correspondence. Vehicle inspection can be arranged where required.

Engine Failure

Timing chain stretch, guide failure, compression loss, bearing failure, oil starvation. Pre-existing vs owner-caused determination with reference to manufacturer service data.

Turbocharger Failure

Underboost, overboost, oil feed restriction, bearing failure. Root cause analysis distinguishing design fault, wear, or abuse from documented diagnostic findings.

Electrical & Electronic

ECU failure, wiring faults, sensor failure, CAN bus issues. Fault code interpretation and root cause analysis from diagnostic scan records.

Transmission

Gearbox failure, clutch, differential, DSG and automatic transmission faults. Pre-existing defect analysis for used vehicle disputes across mileage and ownership timeline.

Known Manufacturer Defects

Technical service bulletins, known design faults, model-specific failure patterns. Applied to mileage and ownership timeline to establish pre-existing defect status under the Consumer Rights Act.

Used Vehicle Disputes

Consumer Rights Act s.9 satisfactory quality analysis. Finance provider disputes under s.75 CCA. Financial Ombudsman Service submissions. Small claims and county court proceedings.

How It Works

The Process

Four steps from initial contact to signed report. Typical turnaround is five to seven working days from receipt of all documents.

1

Submit Documents

Send inspection reports, diagnostic records, warranty documents, and correspondence by email. The more documentation provided, the stronger the output.

2

Briefing Call

A short call to cover the background, ownership timeline, and technical context. Your knowledge of the vehicle is captured alongside the paperwork.

3

Report Prepared

Full CPR Part 35 compliant expert technical report. All documents listed. Opinions clearly stated and qualified. Limitations acknowledged throughout.

4

Signed & Issued

Final PDF issued with wet signature and statement of truth. Report reference AUTOD-EXPR-[YEAR]-[NUMBER] assigned. Ready for direct submission.

Fees

What It Costs

Fees are agreed in advance. In many cases where a claim succeeds, the expert witness fee is recoverable from the respondent as part of the settlement.

"The report was submitted to the Financial Ombudsman Service. The FOS subsequently indicated, on the basis of rule 11.2, that the respondent companies had no standing to contest the claim. The expert witness fee was validated by the FOS and added to the claim as a recoverable cost."

Joel Diack, Rugby — Range Rover Velar dispute — April 2026 · Ref AUTOD-EXPR-2026-1322
£2,500
+ VAT · Standard report fee

Complex multi-party cases or cases requiring physical vehicle inspection are quoted individually. Contact first to discuss your situation before committing.

Start Your Enquiry

Send the case documents and a brief outline of the dispute. I will come back to you within one working day to confirm whether the case falls within scope and what the fee will be.

Email to Enquire 01788 877660

Disclaimer. This service provides independent expert technical opinion only. Autodiag is not a firm of solicitors and does not provide legal advice. Reports are prepared solely on the basis of documents provided and the briefing given — Autodiag is not liable for the accuracy of information supplied by the instructing party. Opinions may be revised if further evidence emerges. The expert’s overriding duty is to the court, not to the instructing party. Autodiag holds motor trade, public liability, and employers’ liability insurance and operates as a fully VAT-registered sole trader (VAT No. GB286590361). Reports are prepared in compliance with CPR Part 35 and Practice Direction 35.