VSC OFF/ TC OFF/ Flashing Engine Warning Light

[Ben O]

Hi all

I have noticed my 1.8 VVT-i Avensis has been showing these warning lights, the VSC and the TC OFF lights. This along with the check engine warning light which flashes whilst accelerating.

To my incompetence when it first came up, I didn't do anything until i realised the car was misfiring and duly serviced the car changing all the plugs and filters. (I think they were original plugs and original air filter after 129,000 miles!!!).

I got a mechanic to clear the codes but they came back on. Disconnected the Battery and all the codes went off & then went back on. 

When I had the codes checked the first time, it indicated a misfire on cylinder 2 which was fixed with the new plugs.

I have seen somewhere on this forum about past owners experiences with this however I believe a lot of these were diesels whereas I have a petrol.

 

Is there any long term solution that I can do, also did notice today the car was understeering a little bit so the VSC OFF is real not just for show.

 

Many Thanks

Ben 

[avetoy]

Hello.

"If the check engine light starts flashing, that means that the problem needs immediate attention and the car should be brought to workshop instantly..." (That is Mr T opinion).

Do you know what the fault codes were? 

[Gerg]

I don't have an Avensis, but from what I've gathered on here, if there is an engine problem logged, then the ABS/VSC/TC will often light.  I think the problem here is likely to be the engine fault.  Perhaps someone can correct me.

From about the age of 17 years old, our 2001 vvti Corolla began to have an ignition coil failure every year or so (not the same cylinder!), I would think that in your situation, given the cars age, and the fact that worn spark plugs give the ignition coil insulation a marginally harder time, an ignition coil failing must be a possibility on the list of culprits.  But on the Corolla, the EML was on hard, and not triggered by acceleration.

I doubt that the coils are the same as the Corolla, but the design/technology will be similar, and probably the same manufacturer.

If you do go down that route of coil replacement (after checking the codes again, and if it's a coil fault on cylinder 2, swapping coil 2 with one of the other ones, and seeing if the fault code changes!), then of the three coils I have bought, marginally the cheapest was the last one, an NGK, for £31 off an eBay UK seller. But the ones bought locally were only £12 more. The Toyota dealer price for the Corolla coil was about £185. 

The coil failure was sometimes obvious when driving, but once it was not.  But on that car, at all times a solid EML light was triggered and a fault code logged.

I can see no outward difference in build quality between the original and aftermarket coils (an Intermotor brand and two NGKs).

[mrfixer]

A 'poke and hope' approach is not the way forward.  Get the codes read by someone with appropriate equipment - ideally Techstream.  A flashing light is usually a pollution control fault - ign system, O2 sensor/injector fault etc etc..

[Ben O]

Hi all thanks for the responses

When the flashing engine light came on, I left it for about 3-4 weeks, suspected a misfire.

When the car was serviced by a mechanic, I watched and helped, he changed all the plugs said they looked original and I agreed with him. He then plugged in his equipment which confirmed that the light was as a result of a misfire. 

The code read 'misfire cylinder 2' to my memory.

He then cleared the codes as this had been fixed.

But the light came back so I disconnected the Battery and the light went away and then came back on.

Coils is a good shout it could be faulty coils. I will look into it.

 

[Gerg]

If your friendly mechanic chap is happy reading codes for next-to-nothing, then code reading would be the next step I would definitely take.  Actually, I'd get them read regardless!

And/or, I'd look into buying or borrowing a code reader. They are a very reasonable price (£10 - 12 upwards for the an ELM327 Obd2 dongle type, to work with an android phone and, say, Torque app.) and a great investment. 

The misfire (if that is what it is) can start to damage the catalytic converter (through local overheating of the cat. via the unburnt fuel hitting it), so this is not good to leave!  And the MoT implications, of course. 

[Ben O]

When we read the code initially it said it was a misfire, but we repaired that so mechanically should be fine. 

I would swap the coil packs over but only problem is I don't have a code reader, so cant determine if the fault would be down to coil packs. 

What code reader would you recommend works with an iPhone best I will look into buying one.

 

Side note - I remember spark plug 2 was covered in black so was a misfire.

[Gerg]

I've not used an OBD2 dongle with an iPhone (when I had one!), so I'd have to leave that to others.  I think there are issues with the way Apple lets the bluetooth connectivity function with other non-Apple devices which makes this much more difficult.  But I'm a long way from knowing the details.  If you can find one, it will probably be much more cash!

If you can borrow an Android phone or tablet off someone, that actually might be the easiest route.

For my Android phone, I got the predecessor to this dongle below, a few years back, it was £10 in 2016.  It seems to work ok, and if yours doesn't you could always return it...

https://www.amazon.co.uk/Torque-Pro-Elm-327-Bluetooth/dp/B01AC7I7BO/ref=sr_1_3?crid=1FNK7VK3KGBMH&dchild=1&keywords=torque+elm327+pro&qid=1606483226&sprefix=torque+elm%2Caps%2C170&sr=8-3

But there is plenty choice out there, and other folk might have their own favourites.  I think any working Android phone will do to connect it to - something hiding at the back of the draw, as long as the Android version will support the app. you choose.  Some apps will give you the fault code and a very simple explanation in words as to what the code means.  

Worth noting this message at the end of that Amazon listing:

"Please note this is a engine code reader, it will not reset service lights, airbag, ABS or SRS lights."

It also gives a list of OBD protocols that it will fit, but I think that is a pretty normal group to cover, and yours would be in it.

[avetoy]

Perhaps you already have it but here is link to most common engine fault codes list (Toyota):

https://www.engine-light-help.com/toyota-check-engine-light.html