Yellow warning light on stable

[Spice61]

Changed Key battery!
As it warned low battery!
Would this constitute yellow service engine soon light?

 

[scotman]

No. Can you get someone to plug a generic scan tool into the dlc under the steering column? Im not familiar with what an auto parts store offers in Thailand to help owners pinpoint the needed part.
Do you have "capless fuel filler" on Thai version of Fiesta? I know that you have right hand pilot. But unsure of what else is different.
Do you have 1.6 dohc or some other? Just curious.

 

[Handy Andy]

A Yellow "Service Engine Soon" or "Check Engine" light means something serious is going on.

If you're seeing this guy on your Dash...
Yes, it's a problem, or you have several problems can be under this light.
​

Low Battery? you have this guy on a the same time
...

This one means charging issues...
(Your battery)
​

If you only have the YELLOW Engine light, then the condition is something directly with engine - perhaps a fuse blew to a sensor or you have a wiring issue causing a drain on the battery. (Low battery "message" on the Console)

IF only the RED light is on, then the ALTERNATOR or the CHARGING system needs help.

IF BOTH are on, then the condition could something as simple as a broken belt. Low voltage, and the Alternator is not showing it's charging the system (returning power back into the system)

 

[Spice61]

No. Can you get someone to plug a generic scan tool into the dlc under the steering column? Im not familiar with what an auto parts store offers in Thailand to help owners pinpoint the needed part.
Do you have "capless fuel filler" on Thai version of Fiesta? I know that you have right hand pilot. But unsure of what else is different.
Do you have 1.6 dohc or some other? Just curious.

Hi
Thanks for the information!!
Yes my fiesta does not have a fuel cap as you say!
Not sue on Engine size ?
It’s a Sports edition I think as it is an S model
2014 late , first bought in March 2015

 

[Spice61]

Hi
Thanks for the information!!
Yes my fiesta does not have a fuel cap as you say!
Not sue on Engine size ?
It’s a Sports edition I think as it is an S model
2014 late , first bought in March 2015

Had a plug into scan done , and it is a Catalytic converter warning code 1 ?
I think 1st sensor?

 

[Spice61]

Had a plug into scan done , and it is a Catalytic converter warning code 1 ?
I think 1st sensor?

 

[Spice61]

Had reset done and the car ran for 80 km before service Engine Soon light came back on ?

 

[Spice61]

Had reset done and the car ran for 80 km before service Engine Soon light came back on .
Sorry the key battery was a dashboard warning, saying change key battery soon!.
Not the main battery warning!!

 

[Spice61]

My Ford Manual is all in Thai!!!
So cannot read it!!!

 

[econoboxrocks]

You may need to replace the sensor.

 

[scotman]

Sounds like an oxygen sensor. Being a four cylinder engine, there is only 1 bank. But, there are two O2 sensors. The fast sensing "upstream O2" that is just ahead of the catalyst and then you will see the "downstream O2" which is located on the tail end of the head pipe just before the resonator. It functions as a confirmatory or slower reading sensor. With average use, it might be wise to change both oxygen sensors. Primarily because they greatly affect the longevity of the catalyst. Which is much more costly than a pair of O2 sensors.
Plus there is the added bonus of improved fuel economy and drivability.

 

[Handy Andy]

Ok, well doesn't sound like it is any of my suggested - LOL - ah well. But we did narrow it down - it was not a charging problem.

I do find it interesting you have "low battery" on the key - this would not set a trouble code. so I think you fixed that when you replaced the battery in the key.

Doesn't mean the Key is perfect - it could be damaged from something else affecting the buttons on it. The battery, any battery in a key fob with a stuck or shorted out button is going to go dead pretty fast but in the process it will fight you when it comes to even using your car.

Glad to see you found a Reader and got the DTC code. - Catalytic converts the bad exhaust into something less toxic - so if one sensor is not working or "PROPERLY CONNECTED" yes it would set a dash board light.

I capitalized "Properly Connected" for a reason - the Sensor uses power from the system to heat up an element so it can use the element to sniff the exhaust for excessive Oxygen or Not Enough Oxygen - but to do that it needs a lot of current from the battery to heat the element up to make it work - if a fuse blew or the sensor connector is damaged - the Check Engine light and the stored Code is letting you know there is a problem and it thinks it's with the O2 sensor.

But I don't know when or how this all started- were you just driving along? Or tried to start the car one morning and had problems starting the car? Ran over a bump in the road and it answered back with a loud "CLUNK" onto a heavy rain and got the vehicle stalled in a pool of standing water? We just don't know - you seem to have just started having these problems - so O2 sensors just don't "quit" unless there was some type of problem you would start to feel, know what, the vehicle is doing - leading up to this.

So following @scotman lead, did you have drive problems before?

Like;

• - stalling?
• - running rough?
• - hard to start?
• - just filled up gas tank and now this...?

Usually the O2 sensor starts to show problems by the mileage on the Odometer - so more miles driven by the car, the more likely something can go wrong. But you'd notice problems with poor performance - some actions like hesitation and low acceleration - are right away noticeable - caused by things like poor gas or fuel with water in it - you don't get very far or drive well with bad fuel.

It can damage sensors - O2 being one of them.

But if the exhaust pipe got damaged from striking a pothole - the sensor may not be damaged, the Catalytic converter downstream from it is and the O2 sensors are fighting - in contention; with one of them - the first one (Upstream towards the motor) - being the most sensitive to the changes in the exhaust - setting the light on the dash saying something like "I can't handle this - fix it". Cars don't have a conscience - but the error code developed from all this is simply letting you know there is something going wrong - fix me before I really blow-up.

But too, O2 sensors have "heaters" they need to warm up quickly once the car is started so they can do their job in trimming the air-fuel mixture - which gives the Fiesta the fuel economy and drivability. These sensors monitor the results by using the exhaust - they know or sense (by fumes the sense of smell) the Engines condition by knowing what is in the exhaust to tell the fuel system what to do next.

IF you have an Automatic - there are more than one type of system "sniffing" the motor - which if one is not right - may tell another to work harder at making the motor "smell this way" because it "sniffs" and says something it is doing is wrong.

That could be from the EGR valve - Exhaust Gas Recirculation Valve - if that is getting plugged - then the O2 sensor knows it and tell the system it has a problem and if this keeps going on in a cycle of your driving - the Light will go on on the dash.

So if the vehicle doesn't have a lot of miles on it - but lights up the Check Engine light - the scan tool says it's the O2 sensor?

This seems a little premature to just think it's bad - but if you live in an area where flooding, poor fuels or otherwise a lot of idling is occurring while your stuck in traffic - I can see why the light would turn on in the dash - lack of ability to drive the engine to get it hot and moving enough to purge the combustants (exhaust by-products) still trapped inside - out and allow fresh air into the motor and get it to breathe and clear fumes from systems.

 

[scotman]

Misfueling or getting contaminated fuel is also a possibility. I have experienced contaminated fuel here in Michigan.
Water in fuel is pretty uncommon now because of the relatively high amount of ethanol in regular motor fuels keeps that issue very uncommon. But, diesel fuel in gasoline is still a possibility. Mostly at stations that purchase fuel from refiners as bulk load buyers (there is an industry term for non affiliated distribution, that i can't recall) that might have less than kosher quality gasoline. Third world distribution and storage systems are anyone's guess regarding the potential for problems

 

[Spice61]

Ok, well doesn't sound like it is any of my suggested - LOL - ah well. But we did narrow it down - it was not a charging problem.

I do find it interesting you have "low battery" on the key - this would not set a trouble code. so I think you fixed that when you replaced the battery in the key.

Doesn't mean the Key is perfect - it could be damaged from something else affecting the buttons on it. The battery, any battery in a key fob with a stuck or shorted out button is going to go dead pretty fast but in the process it will fight you when it comes to even using your car.

Glad to see you found a Reader and got the DTC code. - Catalytic converts the bad exhaust into something less toxic - so if one sensor is not working or "PROPERLY CONNECTED" yes it would set a dash board light.

I capitalized "Properly Connected" for a reason - the Sensor uses power from the system to heat up an element so it can use the element to sniff the exhaust for excessive Oxygen or Not Enough Oxygen - but to do that it needs a lot of current from the battery to heat the element up to make it work - if a fuse blew or the sensor connector is damaged - the Check Engine light and the stored Code is letting you know there is a problem and it thinks it's with the O2 sensor.

But I don't know when or how this all started- were you just driving along? Or tried to start the car one morning and had problems starting the car? Ran over a bump in the road and it answered back with a loud "CLUNK" onto a heavy rain and got the vehicle stalled in a pool of standing water? We just don't know - you seem to have just started having these problems - so O2 sensors just don't "quit" unless there was some type of problem you would start to feel, know what, the vehicle is doing - leading up to this.

So following @scotman lead, did you have drive problems before?

Like;

• - stalling?
• - running rough?
• - hard to start?
• - just filled up gas tank and now this...?

Usually the O2 sensor starts to show problems by the mileage on the Odometer - so more miles driven by the car, the more likely something can go wrong. But you'd notice problems with poor performance - some actions like hesitation and low acceleration - are right away noticeable - caused by things like poor gas or fuel with water in it - you don't get very far or drive well with bad fuel.

It can damage sensors - O2 being one of them.

But if the exhaust pipe got damaged from striking a pothole - the sensor may not be damaged, the Catalytic converter downstream from it is and the O2 sensors are fighting - in contention; with one of them - the first one (Upstream towards the motor) - being the most sensitive to the changes in the exhaust - setting the light on the dash saying something like "I can't handle this - fix it". Cars don't have a conscience - but the error code developed from all this is simply letting you know there is something going wrong - fix me before I really blow-up.

But too, O2 sensors have "heaters" they need to warm up quickly once the car is started so they can do their job in trimming the air-fuel mixture - which gives the Fiesta the fuel economy and drivability. These sensors monitor the results by using the exhaust - they know or sense (by fumes the sense of smell) the Engines condition by knowing what is in the exhaust to tell the fuel system what to do next.

IF you have an Automatic - there are more than one type of system "sniffing" the motor - which if one is not right - may tell another to work harder at making the motor "smell this way" because it "sniffs" and says something it is doing is wrong.

That could be from the EGR valve - Exhaust Gas Recirculation Valve - if that is getting plugged - then the O2 sensor knows it and tell the system it has a problem and if this keeps going on in a cycle of your driving - the Light will go on on the dash.

So if the vehicle doesn't have a lot of miles on it - but lights up the Check Engine light - the scan tool says it's the O2 sensor?

This seems a little premature to just think it's bad - but if you live in an area where flooding, poor fuels or otherwise a lot of idling is occurring while your stuck in traffic - I can see why the light would turn on in the dash - lack of ability to drive the engine to get it hot and moving enough to purge the combustants (exhaust by-products) still trapped inside - out and allow fresh air into the motor and get it to breathe and clear fumes from systems.

 

[Spice61]

You could be spot on about the water on the road!!
I live off the main road and the dirt road gets flooded regularly with large puddles of water!!
The light first came on after a long trip and I drove slowly through a few large puddles of water!
Then I put the car into idle for a few minutes to open my sliding gate!
As I pulled into the driveway the yellow check engine light came on!!
But it was then reset by my friend after he checked it with his code reader!!
It came back on after about driving 80 kms??
I was just driving the car this time!!
What do you think?

 

[Spice61]

Misfueling or getting contaminated fuel is also a possibility. I have experienced contaminated fuel here in Michigan.
Water in fuel is pretty uncommon now because of the relatively high amount of ethanol in regular motor fuels keeps that issue very uncommon. But, diesel fuel in gasoline is still a possibility. Mostly at stations that purchase fuel from refiners as bulk load buyers (there is an industry term for non affiliated distribution, that i can't recall) that might have less than kosher quality gasoline. Third world distribution and storage systems are anyone's guess regarding the potential for problems

Yes 👍 I did fill the car!
But only with E95 premium at large Esso station!
I did drive through two large puddles of water after a long drive and then put the car into idle while I opened my sliding gate!
The check engine light came on when I pulled into driveway!
But the next day I had my friend check the status that said it was the Vatslytic converter , something about section 1 or system 1 ?
He then reset it.
The car drove for about 80km before the light returned!
The car seems to be running well !
Very smooth and no problems?
Does this give you any more clues?

 

[Handy Andy]

We're thinking - but puddles - not likely. This may be fuel related - as wrong fuel - but not from your end - poor fuel at the station - end.

You can't be held liable for a mistake at the station - but for now since you're running ok, let's get some mileage to drive off the fuel - for the change in BLEND of fuel might be setting off the light. Blends - like in US here, Summer fuels are "pushed down" to reduce volatility and boiling in hot weather - while in Winter - that kind of blend is more volatile with stuff to make the car start easier and give better emissions when it's really cold outside.

Water from the puddle would only affect the pipes and perhaps cast moisture onto the harness if the water was really deep, but if water got into the exhaust pipe or thru the snorkel for air intake - that would also plug up an air filter with water - might want to open the hood and check the Air cleaner - it will need a T25 Torx tool to loosen the 4 bolts and (maybe) 1 side bolt - so you can pop the cover off and see if the filter is soaked with water.

Not sure if that blend mix could affect you, but you're running a E95 stuff means there more alcohol than gas in the mix as Ethanol - so this may cause a knock sensor to hear something then set a condition that forces the O2 sensor to monitor and if it cant adjust timing - it may think the sensor is over-reacting.

The vehicle has a "time - monitor" that places values in an area of memory in the PCM as it runs the motor - think of this as a "Hours of run time" clock - if you change fuel to say a lower grade - but you've used premium ever since you've owned the car - that area of memory in the PCM (it's chart of values for specific conditions and run times) is checked on a run-time basis - if something is not right - like knock or a potential mis-fire detected - then the PCM places itself in a mode that forces real-time data to get compared to that stored data and it can set codes if things are not matching up in the averages it thinks they should be.

It's a long shot but it just might be the "blend" is causing the issue - keep an eye, and a feel - out for how your car runs these next few times with this fuel. IF the sensor is going off, you only have two choices - one - to drive off the tankful you have now, or siphon it out and put in new fuel from a different station.

 

[Spice61]

Thanks for your replies!
My other problem with the car is a road noise ?
The car seems to have a whirring noise and we cannot seem to locate the exact spot it’s coming from?
We thought it may have been a lumpy rear tyre as that was what my friend suggested!
As it was on a showroom floor for some time?
But I replaced the tyre with new tyre and still have the same noise?
We checked the bearings by spinning the wheels but did not seem to pinpoint any wheel creating a noise whilst spinning?
Although the tyre man put on hoist and says the back passenger wheel has a slight vibration when he spins it?
He told me to put my hand on the shock absorber when he spun the wheel?
You could feel a vibration going through the shock absorber!
We tried the other rear wheel doing the same thing and it had no vibration through the shock absorber?
But there was no whirring sound on spinning the wheel with the vibration?
What are your thoughts?

 

[Handy Andy]

The technique he did, was to show or demonstrate the bad bearings that you have in the rear hub. So usually they replace both sides as a pair to just keep the vehicle driving straight. So bad flooded potholes are problems for any type of vehicle - they may be tough little vehicles but they are not submersibles nor designed at become a torpedo like you'd see in a James Bond Film.

Might want to go back to the ODB Scan tool and take another look into the Check Engine light - it may be a combination of factors - including a bad rear wheel hub sensor causing the ABS, Trac Control - even Hill-Assist (if you have it) these can act up and cause conditions of drag on the motor hurting your fuel economy in the process let alone add more wear and tear on the motor and drivetrain you don't need.

 

[Spice61]

The technique he did, was to show or demonstrate the bad bearings that you have in the rear hub. So usually they replace both sides as a pair to just keep the vehicle driving straight. So bad flooded potholes are problems for any type of vehicle - they may be tough little vehicles but they are not submersibles nor designed at become a torpedo like you'd see in a James Bond Film.

Might want to go back to the ODB Scan tool and take another look into the Check Engine light - it may be a combination of factors - including a bad rear wheel hub sensor causing the ABS, Trac Control - even Hill-Assist (if you have it) these can act up and cause conditions of drag on the motor hurting your fuel economy in the process let alone add more wear and tear on the motor and drivetrain you don't need.

Thanks 🙏
For your replies
Now this car is seemingly like a lemon?
Now tha AC is blowing its fuse around every 20 minutes?
What are your thoughts?