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A vehicle diagnostic scan at Route 66 Auto Repair in Upland reads every computer module in your vehicle, not just the engine. That includes ABS, airbags, transmission, body, climate and network modules. It is the scan to book after a warning light, before a road trip, after body work or when you want a baseline. The written report lists every stored code by module, with what it means and what we would test next.
When to book a full vehicle scan
- An ABS, airbag, traction or other warning light is on
- Several lights came on at once after a battery change or jump start
- You finished body or glass work and want to confirm no faults were left
- Before a long trip or after buying a used car
- Features like power windows or climate control act strangely
How is a full scan different from a code read?
A basic code reader talks to the engine computer through the OBD-II port. Modern vehicles have many more modules, and each stores its own faults. A full scan polls every module the vehicle has and lists each one's status, even those with no faults.
For each code we record whether it is current or history, and the freeze frame data when available, which shows the conditions when the fault set. We check readiness monitors to see if codes were cleared recently. Communication faults between modules get special notice, since they often point to wiring or a low battery rather than a failed module. We do not clear codes before you have seen the report.
What the scan report lists
- Every module found, and whether it reported faults
- Each code, its description and current or history status
- Freeze frame data when stored
- Readiness monitor status
- Communication faults between modules
- Our recommended next test for each active fault
How we run a full vehicle scan
Step 1: Battery check
Low voltage can cause false codes, so we check it first.
Step 2: Scan every module
The scan tool polls every module the vehicle supports.
Step 3: Record and review
Codes, status and freeze frames are recorded before anything is cleared.
Step 4: Report
You get the list, explained, with next steps and costs for any testing.
What's included in a vehicle diagnostic scan
Included on the work order
- 01Battery voltage check
- 02Scan of all supported modules
- 03Code list with current or history status
- 04Freeze frame and readiness monitor review
- 05Plain-language explanation of each code
- 06Written next-step recommendations
Which scan results are need-now?
Need now: call
- Airbag system faults
- ABS or stability control faults that disable those systems
- Active engine or transmission faults with a drivability change
Need later: book
- History codes that have not returned
- Body or comfort module faults with no safety impact
How pricing and timing work
The fee is stated at the counter before we scan. A scan is quick. Diagnosing a code to its cause is a separate step, and the written estimate tells you what that testing involves before we do it. The diagnostic fee applies to approved related repair. AAA members save 10% on parts and labor, up to $75, with the card at time of service.
What to read next
If you only need engine codes, OBD-II scanning covers that report. When a code needs tracing to a cause, auto diagnostic testing is the next step. ABS codes lead to ABS system diagnostics. Buying a used car? A full-module scan is part of the deluxe pre-purchase inspection, and you can check open recalls on the NHTSA recall lookup (opens in a new tab).
Frequently asked questions
Does a code tell you what part to replace?
No. A code tells us which system noticed a problem. Testing finds the cause. The report explains each code and what we would test next.
Will you clear my codes?
Not until you have seen the report. Clearing codes erases useful information. After repairs, we clear them and confirm they do not return.
Why scan after body work?
Collisions and repairs can disturb sensors and wiring for airbags, parking aids and lights. A full scan confirms nothing was left in a fault state.