// Workshop Guide

How to Charge Properly for Diagnostic Labour

Published by DiagEdge  ·  5 min read

Walk into most independent Australian workshops and ask what they charge for a diagnostic check, and you'll hear something between A$90 and A$140. Ask a main dealer and you'll hear A$150 to A$220 — sometimes more. The gap isn't just about brand prestige. It reflects a fundamentally different understanding of what diagnostic work actually costs.

The uncomfortable truth is that most independent workshops are subsidising their customers' diagnostic work out of their own margins — and most don't even realise it.

1. The Real Cost of Diagnostic Work

Diagnostic work is fundamentally different from servicing or repair work. When a technician services a car, the time, parts, and labour all map predictably to an outcome. Diagnostic work is investigative — the outcome is genuinely unknown at the start, the time required is variable, and the expertise required is far higher than for routine maintenance.

Consider what goes into a single diagnostic job:

Technician time — often 1–3 hours for an intermittent fault, before any repair work begins
Diagnostic equipment — a professional multi-brand scan tool costs A$3,000–A$12,000, with annual software subscriptions on top
Technical data access — wiring diagrams, technical service bulletins, and workshop databases cost A$150–A$600 per month depending on coverage
Training — keeping a technician current on diagnostics across multiple makes requires continuous investment — particularly with the growth of EVs and advanced driver-assist systems in the Australian market
Your time — every senior tech interruption has a real cost

When you add all of this up and spread it across your diagnostic jobs for the year, the cost per diagnostic hour is often A$20–A$40 higher than your general labour rate — before you've earned a cent of profit.

2. How to Calculate Your True Diagnostic Labour Rate

Start with your base labour rate — whatever you charge for servicing and mechanical work. Now add the following:

// Diagnostic Rate Formula

Base labour ratee.g. A$120/hr
Equipment cost allocation (annual cost ÷ diagnostic hours/year)+A$12–20/hr
Technical data subscription (monthly cost ÷ diag hours/month)+A$5–12/hr
Training investment recovery+A$8–15/hr
True diagnostic labour rateA$145–167/hr

Even at A$145–165 per hour, a diagnostic check that takes 90 minutes should be billed at A$215–250. If you're charging A$110 for a "diagnostic check" that takes your best technician 90 minutes plus your time for 15 minutes to discuss findings, you're running that job at a loss.

3. How to Present Diagnostic Charges Without Losing Customers

The most common objection to raising diagnostic rates is customer pushback — particularly the "the garage down the road does it for free" comparison. Here's how to reframe the conversation:

Be transparent about what they're paying for.

Tell customers upfront: 'Our diagnostic fee is A$X. That covers specialist equipment, technical data access, and a full written report of findings. You're not paying for us to plug in a code reader — you're paying for a qualified technician to investigate and diagnose the fault accurately.'

Offer a diagnostic report.

Give customers a written summary of what was found, what was tested, and what the recommended repair is. This makes the charge feel tangible and professional. It also significantly reduces the 'but you didn't do anything' objection.

Separate the diagnostic from the repair.

Don't absorb the diagnostic cost into the repair quote. Charge for the diagnosis, then quote the repair. Customers who accept the repair see the diagnostic charge offset — customers who go elsewhere have still paid for your time, which is fair.

Qualify the 'free diagnostic' competition.

A free code read at a parts shop is not the same as a professional diagnosis. Most Australian customers understand the difference when it's explained clearly. Those who don't are likely to be more trouble than they're worth as long-term customers.

4. How AI Diagnostic Tools Change the Maths

The economics of diagnostic work are changing rapidly. AI-assisted diagnostic tools don't replace a technician's judgement — but they dramatically reduce the time a technician spends stuck, researching, or pulling in help.

In a typical workshop without diagnostic AI support, technicians spend 15–30% of their diagnostic time either stuck on a fault pathway, waiting for help from a senior tech, or doing manual research. In a workshop of three technicians with four daily interruptions each averaging 20 minutes, that's four hours of billable time lost every single day — around A$480 at a standard Australian labour rate.

AI tools like DiagEdge give every technician access to a structured diagnostic pathway immediately. They can work through faults independently, reducing interruptions and increasing throughput. The result is more diagnostic jobs completed per day, fewer write-offs on diagnostic time, and a more confident, capable workshop team.

For a workshop spending A$50 per month on a diagnostic AI subscription, recovering even one hour of previously lost diagnostic time per week more than covers the cost — typically within the first week of the month.

The Bottom Line

Properly pricing diagnostic work isn't about gouging customers — it's about accurately reflecting the true cost of skilled, equipment-intensive, investigative work. Under-pricing diagnostic time is one of the most common and most damaging habits in Australian independent workshops, and most owners only realise the scale of the problem when they sit down and do the maths.

Start by calculating your true diagnostic rate. Apply it consistently. Communicate it confidently. And invest in tools that help your team diagnose faster and more accurately — because diagnostic throughput is as important as diagnostic pricing.

Try DiagEdge in your workshop

Give every technician access to AI-powered diagnostic guidance across 6 specialist modules. First month just A$1.

Start for A$1 today