Abs Light, Vsc Light And (!) Light

[Samuk]

Hi All

Thanks for the forum I have a 2008 Toyota Prius from new and done only 19k.

Last week it showing the ABS light, VSC light and (!) light when Im driving.

​I can drive normally but worried and Toyota said that it is out of their guaranty.

Any advice Toyota says may be wiring loom under the seats are damaged or ECU

replacement that's going to cost my arm and leg.

Your help is appreciate.

Thank you all,

Samuk

[MEP's Yaris GS]

It's all hearsay, you need to get it into a garage to be fault code read, anything else is stabbing in the dark and potentially wasting money.

[Samuk]

Hi Jonathan

Thanks for the post. Yes I have been to Toyota but their response is not very good codes they gave me is

Air Bag DTC B1653,B1655,B1821,B1826 OSF, NSF seat wire harness req Repair and

Transmission ECU Dtc C2300,C2318 Actuator System malfunction and Req further Diagnostic

This is the report I have got,

Thank you,

[Grumpy Cabbie]

First thing - Check your 12v, especially if it's the same one from new.

Don't trust the internal computer. Get a multimeter and check it from the 12v Battery itself.

The car will give all sorts of weird and wonderful error messages and lights when the 12v is failing. People think their car is broken but in 8/10 times it's the 12v. If nothing else, it's a cheap fix and worth checking regardless.

Oh and they cost about £90 fully fitted by Toyota. Non Toyota batteries are available but you may have to tinker with the vent hose. Search this Prius section for many many many other threads about failing 12v's.

[Devon Aygo]

The B codes are are body related and will be your airbag issues, is your SRS warning light on ? as these codes would not set the VSC, ABS ligthts, if your SRS light is not then these codes should be ignored/cleared.

C2300 & C2318 both relate to issues with the transmission park brake, if the park button is working as normal I would suggest your 12v Battery is failing and setting issues with the transmission park brake actuator. Have your 12v battery/checked and replaced if required and the codes deleted afterwards.

[Samuk]

Dear all

Thank you very much for your replies I will check the Battery hopefully(tomorrow)

can come back to you.This the Battery from new and Battery is in the boot is in it.

Kind regds,

Samuk

[ph47mf]

i suspect it's something else as i have the same problem, the car drives completely fine, the warning lights come and go whenever it feels like it, my 12v was changed last year. i too wonder what it is.

[Grumpy Cabbie]

If the Priuschat was up and running (they've had issues the last few days and have been offline) you could search literally hundreds of posts with alarm issues, abs lights, weird electrical errors and in 8/10 cases it's a failing 12v. It's always the first thing to check if the car is otherwise running normally.

A good indication (though obviously not fool proof) is that the owners car is usually 5 or 6 years old or about 70k/80k miles and on it's original 12v.

Also, the Prius 12v is very small and very 'weak' compared to a traditional car. In other words in can suffer a much shorter life if it has been allowed to discharge too low for too long. The Prius/Toyota hybrids don't top the 12v up with the same vigour as an alternator car does and thus if you do lots of short trips you maybe experience issues sooner.

If you feel able get a multimeter and check the levels on the 12v in the morning after the car has been left over night. Anything under 12v needs topping. Anything under 11v is duff. Anything at 10.5v is lucky the car is running. If you're able and if applicable, remove the 12v and charge it with a car Battery charge. Be VERY VERY VERY careful if you jump start the car. You CAN fry the electrics in a Prius if it's not done correctly!

You may still be unlucky and actually have a fault on the car, but seriously if the car is 6 years old and/or over 80k miles on the original 12v, that is a good first place to look.

[MEP's Yaris GS]

my 12v was changed last year

That's not to say that it hasn't failed again, if a tad prematurely.

[Samuk]

Dear All

Thanks for the all replies. I did check the Battery today . first thing in the morning Out side temp was 4c

Battery read 9.68v but immediately when the car start it jump up to 10.5 and to 13.4v

Waiting to here from you all,

Kind regards,

Samuk

[paultnl]

9.68v is way too low and could cause all of the problems mentioned. Readings once the car has started are no good as they are bolstered by the output of the alternator.

£90 for a new Battery is money well spent even if it doesn't resolve everything though I would be willing to put money on it doing so.

[Grumpy Cabbie]

Dear All

Thanks for the all replies. I did check the battery today . first thing in the morning Out side temp was 4c

Battery read 9.68v but immediately when the car start it jump up to 10.5 and to 13.4v

Waiting to here from you all,

Kind regards,

Samuk

And you found the reading was less than 10v on a 12v Battery. What do you think you should do? I personally would change the 12v. We've mentioned that a 12v below 11.5v will cause bizarre issues.

You can choose to ignore that and continue to suffer issues. You asked a question on the forum, we've mostly suggested a failing 12v and that it should be replaced. You've found it is indeed a failing 12v and yet still ask what to do?

Using a Prius with a failing 12v will cause poor fuel economy and can put strain on the charging circuits possibly leading to expensive failure of those circuits. One cold morning you'll also find your 12v doesn't have enough power to start the car leaving you stranged - usually when you're in a rush and skint.

Your call.

[timberwolf]

You need a new Battery, it's dead/flat, and I am amazed that you haven't experienced any other symptoms such as slow door locks, failed to unlock doors or failed attempts to switch on to Ready along with the triangle /!\ of doom?

A brand new 12V Battery fully charged should read 12.8V to 13.1V.

The slightly higher voltage is the surface voltage immediately after switching off the charger and this will drop off after the Battery rests.

With the car in Ready that is showing that the battery charging via the DC-to-DC convertor is working at 13.4V.

[barrycoll]

Interestingly, after leaving the Prius on Smart charge with the Ctek charger, for 3 weeks, I then started the car with an outside temp

of 2'C, and plenty of ice to scrape, the car showed 53 mpg after a city/Mway 20 mile run...and on the way homei it ended at 61 mpg despite the deperate chill

maybe the full Battery had contributed to this result

[Joseph D]

Dear All

Thanks for the all replies. I did check the battery today . first thing in the morning Out side temp was 4c

Battery read 9.68v but immediately when the car start it jump up to 10.5 and to 13.4v

Waiting to here from you all,

Kind regards,

Samuk

All of those readings look too low to me. The last one should be ~14.4 V, so I wonder if your volt meter needs to be calibrated.

Not withstanding that, your first reading is far too low, so even if your meter was 1 V out, adjusting for that it is still 10.68 V which is still well passed its prime.

As others have said, it is time to replace and the fixed price service at the dealers of £90 (was £95 last I looked) fitted, is an exceptional deal for a good quality Battery.

If your meter is correct and the charging circuit is only delivering 13.5 V, there may already be damage. It will not bode well for your new Battery, as it will never fully charge with normal around town driving.

[timberwolf]

On my Prius, the charging voltage varies between 13.5 - 13.8 V depending on the state of charge of my 12V Battery and the load on the 12V system. I can't remember what the charging voltage read when my last Battery reached the end of the road. There is a lot of conflicting information posted about the 12V systems on the Prius, some maybe variation in specification between countries and over the models life, and unfortunately some is myth.

As long as the charging voltage is higher than 12 V Battery it will charge the battery. How well? We can guess from a long history of battery problems over the various Hybrid models reported by owners that the charging systems are not the best.

*The car's internal voltage sensor as presented on a data packet via the CAN-Bus and my own DVM match and owing to cost my DVM was tested against some store bought dry-cell batteries.

[Joseph D]

On my Prius, the charging voltage varies between 13.5 - 13.8 V depending on the state of charge of my 12V battery and the load on the 12V system. I can't remember what the charging voltage read when my last battery reached the end of the road. ...

On mine since I installed a new 12 V, I regularly see 13.8-14.0 in regular operation. Occasionally I see 13.5 V (especially if I've externally charged my 12 V overnight). With my old Battery I never saw anything except 14.4 V. Just my observations.

[timberwolf]

No problem. My own observations differ and led me to a different conclusion, i.e. the charging system was nothing to unduly worry about at this time.

I bet the OP did not really want to hear us all say, replace the 12V Battery? Although that would be much cheaper than wiring loom or ECUs problems, so I can't understand the reluctance to replace unless it was an excuse to get rid of the car?

[Grumpy Cabbie]

I bet the OP did not really want to hear us all say, replace the 12V battery? Although that would be much cheaper than wiring loom or ECUs problems, so I can't understand the reluctance to replace unless it was an excuse to get rid of the car?

They'd not be alone. They come on here with a weird or strange error and ask our advice. If it's not what they expected or simple, then it seems to be rejected. You and I all know the 12v issues with a Prius. The dealers still seem to be totally oblivious to it, as are most owners. It seems the simple things are discounted. Also, people seem to have their own idea what the fault is and want us to confirm it. If we all come back with something different, it seems to be discounted. How many times have we all pushed and suggested the 12v here?

There's one on the Priuschat forum at the moment where someone appears to be suffering a failing MFD on a gen2 and possibly a failing 12v. But the dealers and the owner think it's something else and keep pushing that suggestion. Why ask if you know the answer already guys.

Fun n games :)

[Joseph D]

No problem. My own observations differ and led me to a different conclusion, i.e. the charging system was nothing to unduly worry about at this time. ...

Sorry Timber, I hope I did not come across dismissive of your data, I was just adding (hopefully) additional data. I do actually agree with you.

[Samuk]

Dear all

Thank you so much for all advice's and your time As i told yo my car has done only 20 k and 6 years and 4 month old fully

Toyota service thats why im worried,

Today again we have checked the Battery (last night car used for 3 miles) out side Temp was 8C today Battery showing 11.57V .

Tomorrow Im going to call Toyota for replacing a Battery but I have got time end of the week end let all you know what has happend.

Meantime My Toyota can rest in the cold.

Thank you again,

Kind Regards

Samuk

[Samuk]

Dear All

I did change the my prius Battery from Toyota but still dash board lights are on

any more suggestions

Thank you,

[Joseph D]

Dear All

I did change the my prius battery from Toyota but still dash board lights are on

any more suggestions

Thank you,

I'm unclear whether you got Toyota to change the Battery, or you changed it yourself. Did you check the voltage of the new Battery? If so, what was it? If not can you measure it and report the voltage? If it is less than 12.5 V, get hold of a smart charger that is AGM capable and charge up your new Battery for a good 12-16 hours.

If the old battery was disconnected when the the new one was fitted, all existing DTC's will have been cleared, so warning lights still on indicate that you have a genuine problem setting a DTC or multiple DTC's. You now need to take it to Toyota and ask them to read the codes and give them to you. You can then post them here and knowledgeable people here can help you with your next steps.

[Samuk]

Hi Mr Joseph

Battery is changed by Hills Toyota and they charged £96.60 My error codes are Air Bag DTC B1653,B1655,B1821,B1826 OSF, NSF seat wire harness req Repair and

Transmission ECU Dtc C2300,C2318 Actuator System malfunction and Req further Diagnostic

Thank you

[Joseph D]

Hi Jonathan

Thanks for the post. Yes I have been to Toyota but their response is not very good codes they gave me is

Air Bag DTC B1653,B1655,B1821,B1826 OSF, NSF seat wire harness req Repair and Transmission ECU Dtc C2300,C2318 Actuator System malfunction and Req further Diagnostic

This is the report I have got,

Thank you,

Hi Mr Joseph

Battery is changed by Hills Toyota and they charged £96.60 My error codes are Air Bag DTC B1653,B1655,B1821,B1826 OSF, NSF seat wire harness req Repair and Transmission ECU Dtc C2300,C2318 Actuator System malfunction and Req further Diagnostic

Thank you

This looks to be the same list you posted back in post #3.

Did Toyota clear all the codes after they installed the new Battery. If they didn't they should do that and then check for new DTC's if the warning lights come back on.

Let us know how you get on.