Know before you replace parts
ScanWrench captures what your car actually reported, shows you the proof, and tells you the cheapest test to run next. No account. No guesswork.
Available now on the App Store. Bring a compatible OBD adapter. Device Only and Save Nothing keep the scan under your control.
Android beta: ScanWrench 1.0.2 (9) is in limited Google Play testing. Request access
Live scan
7B8F 2A11 C09EPlain-language answers for warning lights, codes, inspections, used cars, and adapters.
Browse all answersSometimes the scan leaves clues, but it cannot prove who cleared the codes or why. Check readiness, permanent codes, MIL status, and scan completeness before buying.
Sometimes—but not everywhere. The allowed number and type of incomplete OBD readiness monitors depend on the vehicle and the current rules where it is tested.
A lit check-engine light usually means an OBD-based emissions test will not pass, but readiness, communication, permanent codes, and local rules also matter. Learn what to check before the inspection lane.
One illustrative P0171 capture shows the difference between receiving a code and choosing the next useful test.
Elevated short-term and long-term fuel trim support testing for a vacuum or intake leak before condemning the catalytic converter or replacing a sensor.
7B8F 2A11 C09E 44D3Illustrative demo data. No vehicle was connected for this example.
The evidence stays technical. The path changes based on what you need to decide.
My light is on
See the evidence, the uncertainty, and the least expensive telling test before anyone starts replacing parts.
Follow the driver pathI am buying a car
Challenge the vehicle, review readiness and fault memory, and keep a VIN-reduced decision record.
Follow the buyer pathI run a shop or fleet
Capture before-and-after evidence, retain unchanged outcomes, and keep the technical record ready for the next person.
Follow the shop path Ask a fleet questionA calm, direct workflow keeps hardware truth, vehicle evidence, and the next decision in the right order.
Measure the exact adapter, transport, and available command surface before describing coverage.
P0171+18.7%731 RPMRecord the returned codes, freeze frame, live context, readiness, and evidence gaps.
Get a conservative test order and a privacy-reduced report with an integrity fingerprint.
Prices are U.S. catalog references. Verified in-app storefront controls availability, localized pricing, tax, purchase, and restoration.
The essential evidence workflow without an account or card.
The complete owner and buyer intelligence workflow.
100 vehicles, unlimited scans, 10,000 sessions, technician handoffs, and Fleet Drift.
Review ShopPermanent Core access. Recurring Academy, deep Buyer Intel, and continuing services remain separate.
Review Founders termsThe Mac and Linux releases are free today. Paid desktop unlocks remain unavailable until cross-device restoration passes its release gates.
Search your model for an instant preview. When you connect, ScanWrench confirms the adapter, connection, and data your car makes available before the scan begins.
Results appear as you type. A model name is a candidate. The exact unit earns the claim. This preview does not verify a physical unit; the app confirms your connection in 5 seconds.
Start typing a brand or model. ScanWrench checks the adapter, connection, and available data before your scan begins.
Compared using each company's official product information. A check means the feature is clearly offered; an X means we could not verify it.
| Workflow | ScanWrench | FIXD | BlueDriver | Carly |
|---|---|---|---|---|
| Tamper-proof scan report | Yes. Proof ID included | No. No named tamper-proof report | No. No named tamper-proof report | No. No named tamper-proof report |
| Find the exact replacement part | Yes. Exact manufacturer part-number search | No. Repair guidance only | No. Repair Reports only | No. Repair guidance only |
| Fresh test before buying a car | Yes. Buyer Challenge | No. Vehicle history is separate | No. No named fresh-test workflow | Yes. Used Car Check |
| Use the adapter you already own | Yes. 5-second compatibility check | No. FIXD Sensor required | No. BlueDriver sensor required | No. Carly scanner required for most features |
The limits stay visible because the evidence has to hold up.
No. ScanWrench uses compatible customer-supplied adapter candidates and checks the exact unit at connection. A model name is a candidate, not a guarantee.
No. Generic OBD, manufacturer-enhanced data, full-system access, read-only functions, and state-changing functions are separate capability levels. ScanWrench reports only the level supported by the exact configuration.
No. ScanWrench preserves observed evidence and offers cited hypotheses plus the next safest test. A code alone does not prove which part failed.
Yes. Choose Device Only to retain data on your device or Save Nothing to erase the session. An account is optional for supported cloud features.
ScanWrench Desktop 0.5.1 is available for Apple silicon Mac. Version 0.6.0 is available for Linux x64 and Linux ARM64. Windows remains unavailable until its exact Authenticode-signed installer passes the release gates.
No. The verified in-app storefront controls availability, localized pricing, tax, purchase, and restoration. Free remains available without a website checkout.
Download the public iPhone app from Apple, request limited Android access, or use a signed desktop release. Windows stays behind its exact Authenticode release gates.
Bring a compatible OBD2 scanner. Read your check-engine code and see the cheapest useful test to run next.
Get ScanWrench for iPhoneAvailable on the App Store3 free scans. No account required.Approved testers can install 1.0.2 (9) now. New volunteers can request tester eligibility without joining a marketing list.
Join the Android betaApproval is manual. The internal test is not the 12-person closed-test requirement.Apple silicon Mac is notarized and stapled. Linux x64 and ARM64 packages include exact detached signatures.
View desktop releasesRelease record and requirements