EPC without error entry

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Lupo.
1.4
APE
'I'm having this problem: the EPC warning light is on, but there are no error codes stored, even after driving for a while.'
All values in the measurement block are within the specified limits.
'An unusual reading on the MSG self-test channel 15 indicates a red outline around the catalytic converter (s).'
in German, what is the plural of 'Katze'?
What am I supposed to understand from this?

Exhaust emissions checked, within acceptable limits.
Lambda value also correct for the second sensor, indicating a lack of oxygen.

Best regards,
Motoextrem.

Translated on 27-10-2026, 6:27.

Are there any errors stored in the instrument cluster?
Are there any error codes stored in the engine control unit?
Are there any errors stored in the transmission control unit?

Which VAG-COM version?
Which interface?
Complete error log excerpt?

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Hello.
Error codes checked in all systems; no errors found.
VAG-COM 512.3
I'm experiencing the same issue with alternative diagnoses that are also available to me.
Launch X431 and 5051.
Okay, so that option is out.
I also rule out a fault in the combination instrument, as it can be observed that...
After the ignition is turned on, the indicator light comes on briefly and then goes off before coming back on again.
as if an error has been detected.

Best regards,
Motoextrem.

Translated on 27-10-2026, 6:29.

Sebastian@OpenOBD wrote:

Complete diagnostic trouble code report?

...please use VAG-COM, and then we can proceed.

...and when it comes to the topic of launches, I'd rather not comment - AAPEX 2005.

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I now have VAG-COM RKS 512.3.
Error codes checked for all systems. (System scan)
Engine / ABS / Combination instrument / Mileage / Central locking - no faults found.
No other systems available.
Hmm.

Translated on 27-10-2026, 6:31.

Motoextrem wrote:

I now have VAG-COM RKS 512.3.
Error codes checked for all systems. (System scan)
Engine / ABS / Combination instrument / Mileage / Central locking - no faults found.
No other systems are available.

As I have said twice already, please post the diagnostic trouble code (DTC) report (auto-scan), even if no errors are stored.