Why engine oil indicator is turned on while the oil level is high?

Question

Today, on my Ford Fiesta Diesel (2009 Econetic), the oil engine orange light is turned on while driving and stayed on since.

Like this (not my car):

Panicked, I checked the engine oil manually using the oil dipstick, it was on the highest mark. There is no unusual noise from the engine, but after coming back home, I noticed a couple of oil stains under the car in the garage (not sure when they're dropped).

The last time that I've changed the oil was 10 month ago, and I've driven like 5000Km since. The car has ~100K Km under the clock.

I took the car to a generic car repair shop and the dismissive guy there said it should be a faulty sensor and does not matter much as long as your dipstick shows the oil in normal range. But I'm still wondering what other issues can cause this, and whether they might be serious enough to stop driving the car to the next mechanic?

Answer 1

This is a sensor to tell you it's time to change your oil. Some are triggered at 3000 miles, some at 5000, depends on the year. check your owner's manual to find out how to reset it. It usually involves a number of steps.

Answer 2

As mentioned in comments above, it seems to be an indicator to check your oil status.

The low level or low pressure indicators shows the oil can with a scale. The amber indicates low level/low pressure, the red one indicates critically low level/pressure.

The "check oil" indicator, or service interval usually follows two rules:

• Mileage since last interval reset.
• Time passed since last interval reset.

The indicator is triggered by the rule, that comes first. It is a software feature so a well-equipped mechanic can change the values.

10 kkm is a reasonable interval for oil change since the additives protecting engine and all the other parts may be burnt and there can be fuel, ashes, etc. contamination it the oil. The time counter it there because the additevies also decay over time.

My advice is to follow these steps and do not skip any:

1. Change the oil / get the oil changed.
2. Change the oil filter / get the filter changed.
3. Change other filters (cabin, air-intake, fuel) / get them changed. - optional
4. Reset the service interval counter.
5. Expect to do this in next 10 kkm again.

There is also a rule of thumb how to read the indicators regarding their colour:

• Blue - High beams: The only blue icon on the dash.
• Green - Informative: headlights, turn signals,...
• Amber - Decent Warnings: Low level of screenwash fluid, ESP off, rear fog lights, ECU in safety mode...
• Red - Serious Warnings: Battery not charging, cooling failure, low oil pressure, brakes failure, handbrake engaged,...

The amber ones indicates warnings that can be anticipated at home. Serious damages may happen when ignored for a long period of time. The red ones indicates to stop immediately or at the closest safe point and solve the problem now.

Answer 3

The light has come on to indicate low oil pressure.

You should get this checked by a good mechanic - not the same one you have already seen.

Some cars will use a pressure gauge or led display to show oil level but most likely not a 2009 fiesta...

I suggest you don’t drive it until the pressure has been checked - you can cause a lot of engine damage...