I used a diagnostic code reader on a used car, and I saw four flashing red monitors. What does this mean?
Mar 11, 2022 at 8:48 AM
What does it me when a diagnostic code reader has four flashing red monitors?
ERICTHOMPSON283
- MEMBER
- 1 POST
Hi,
It may be different based on the scan tool you used and what program you were in when testing, but in most cases, which indicates the monitors have not completed the required drive cycle to properly determine if a circuit is ready for an emission inspection.
For this to happen, either the battery was disconnected, or someone cleared diagnostic trouble codes which will return if repairs weren't completed.
Is this a vehicle you are interested in purchasing? Has the battery been disconnected for any reason recently?
Let me know.
Joe
It may be different based on the scan tool you used and what program you were in when testing, but in most cases, which indicates the monitors have not completed the required drive cycle to properly determine if a circuit is ready for an emission inspection.
For this to happen, either the battery was disconnected, or someone cleared diagnostic trouble codes which will return if repairs weren't completed.
Is this a vehicle you are interested in purchasing? Has the battery been disconnected for any reason recently?
Let me know.
Joe
Mar 11, 2022 at 12:19 PM
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