Check Engine Light: Causes & Solutions

Hello,

I have a question.

Okay, so I have a Skoda Octavia Estate (station wagon) Elegance 1.9 TDI, manufactured in 2003, which actually has pretty much all the available features.

Due to a problem I encountered, I've noticed that the engine check light never comes on.

All the other indicator lights turn on briefly when the ignition is turned on.

No engine check light.

The actual problem can be described as follows:
Occasionally, the coolant light flashes briefly shortly after starting the engine.
After a few meters, the engine cuts out and then restarts, and everything is fine again.
Ideally, this is best done when it's a bit cooler.
Subsequently, the temperature sensor was replaced.
The problem, however, remains. The coolant level is also fine.

Now, occasionally, the engine has been going into emergency mode.
This has happened three times in the last two months, and it's not reproducible.

The engine control unit reported the following error code: 17965, "Boost pressure control, exceeded regulation limit."
However, the engine check light did not come on.

And it was only then that I realized that it also doesn't light up when you turn on the ignition.

Do I not have a check engine light?
How can I find this out?
Or is it even defective?
Can this be tested using actuator diagnostics?

I would be grateful for answers...

Hi, I recently had a 2003 Octavia with an ASV engine, and the coolant warning light was illuminated on the FIS (multifunction display). There were error codes stored in the engine control unit (ECU) and the instrument cluster.
What I mean is, perhaps he doesn't have a check engine light if he has the driver information system (FIS). You should check your owner's manual to see if that's the case; I'd be very interested to know.
When I select the "basic settings" option for the engine control module (ECM) in VCDS, the check engine light starts to blink.

Shadow1975 wrote:

Hello, Can this be tested using actuator diagnostics?

Actuator diagnostics AI. There's a function that activates all the indicator lights.

Hello,

Thank you for the quick responses.

According to the operating manual, the engine check light is an optional feature.
So far, so good.

I can't find any information anywhere about how to determine whether or not I have this additional equipment.

I'll try using the AI-powered actuator diagnostics this weekend, when I'm back at work.
But even then, I don't know if the indicator light might simply be defective, if I even have one...

Okay, here's the translation:

"By the way, if it's important: the engine code is ASV."

Thank you and best regards.

Hi Shadow1975,

Quote:

Due to a problem, I've now noticed that the engine check light never comes on.

Was für ein Problem meinst du da? Boost pressure control?

Bye, Ronny.

Quote:

What kind of problem are you talking about?

Is it a boost pressure regulation issue? }

This issue appeared later and has not been reproducible so far.

The error log entry has not reappeared within the last two weeks, even after being cleared.

However, when I read through various forums, it always seemed to be about the engine warning light...

And that's exactly why it made me suspicious.

Apart from the check engine light, which may not be in its traditional form anymore but might appear as a coolant symbol, are there any other error codes stored in the instrument cluster or engine control unit? Have you already replaced the temperature sensor?

Hello,

Since I really "pushed" the car on the highway about two weeks ago and cleared the error memory, there have been no new entries.

I read out all the error codes last night.

The coolant light (warning light) is also no longer illuminating.

Since I have to get a few other things done next week anyway, the system will be checked again.

But the car actually doesn't have a check engine light.
In the manual, this is listed as a special feature, depending on the engine variant.
It's kind of funny... well... you can't have everything... lol...

Best regards,

Quote:

Due to a problem, I've now noticed that the engine check light never comes on.

The engine control light is on, manufactured by Euro FZ .

Quote:

Occasionally, the coolant light flashes briefly shortly after starting the engine. After a few meters, the engine cuts out and then restarts, and everything is fine again. Ideally, this is best done when it's a bit cooler. Subsequently, the temperature sensor was replaced. The problem, however, remains. The coolant level is also okay.

It's a known issue: the sensor located in the coolant reservoir is likely contaminated and has become insulated. Clean both pins with a bare metal object. If that doesn't work, replace the reservoir.

Emergency program: Start the navigation!

The yellow engine block symbol is the standardized Malfunction Indicator Lamp (MIL), which indicates the readiness of the On-Board Diagnostics (OBD) system by illuminating when the ignition is turned on and then turning off shortly after the engine starts.

Therefore, checking the MIL (Malfunction Indicator Lamp) is the first step in the diesel OBD (On-Board Diagnostics) emissions test.

Your vehicle therefore does not have an OBD system and will continue to display permanent errors as before, via the flashing glow plug indicator.

According to your description, your intermittent 'overboost' error has not been permanently stored in the system's memory because it needs to occur in five consecutive driving cycles for that to happen.

Following the sporadic error, there were twenty cycles without the error occurring. This causes it to be erased from the volatile memory, and everything starts again from the beginning!

To check and trigger the error, you need to drive with full throttle for longer than five seconds; only then will the control unit reduce the turbocharger boost pressure.

Most often, the turbocharger pressure sensor is defective. You can find replacements from brands like Hella or Bosch (around €38 plus VAT).

The note in the operating manual regarding 'special equipment' refers to countries with stricter emission regulations, such as the USA.

hardyscheibe wrote:

Most often, the turbocharger pressure sensor is defective. You can find replacements from brands like Hella or Bosch (around €38 plus VAT).

Sure, here is the translation of the text from German to English, with "meistens" replaced by "sometimes":

"Sometimes, the weather is nice, but other times it is cold and rainy. Sometimes, I go to the park, but other times I stay at home. Sometimes, I eat healthy food, but other times I eat junk food. Sometimes, I am happy, but other times I am sad."