When you close a loaner contract, Dealerware checks the Customer VIN for common entry errors before the contract closes. If the VIN doesn’t pass, you’ll see an error message with the specific issue.
How validation works
Validation runs when you select Finish Contract. Four checks run against the VIN you’ve entered:
- No invalid characters — VINs never contain the letters I, O, or Q
- Exactly 17 characters — no more, no less, no spaces
- Letters and numbers — can’t be all numbers or all letters
- Valid check digit — a mathematical check of the 9th character against the other 16; catches around 98% of typos and transpositions
Note: A VIN that passes all four checks may still not be assigned to a real vehicle. Dealerware will address this in a future update.
What happens when validation fails
If the VIN fails any check, the contract won’t close. You’ll see one of these error messages:
- VIN is required — the field was left blank
- Must be exactly 17 characters with no spaces — the VIN is too short or too long
- Please enter a valid VIN — the VIN failed one or more of the format checks
Correct the VIN and select Finish Contract again.
How this works with your settings
Validation works alongside the Customer VIN Required setting in Settings > Location > Preferences.
- Setting ON, field left blank — contract is blocked
- Setting ON, VIN entered and valid — contract closes normally
- Setting ON, VIN entered but invalid — contract is blocked
- Setting OFF — validation doesn’t run, regardless of what’s entered
Frequently asked questions
When does validation run?
Only when you select Finish Contract. It doesn’t run when adding or editing a contract.
Does this affect me if I don’t use Customer VIN Required?
No. If the Customer VIN Required setting is off, validation doesn’t run.
Is this available on mobile?
Yes. Validation works on both web and mobile.
What if I started a contract before VIN validation was added?
If your Customer VIN Required setting is on, the VIN will be validated when you close the contract — regardless of when the contract was started.
Does Dealerware contact any external service to check the VIN?
No. Validation runs locally in the browser or app with no added wait time.