ABS / VSC / Warning lights all on permanently?

Hi All.

Hopefully someone can help me with this one, I don;t really want to go to the shop for fear of getting overcharged for computer replacement that doesn't need doing?

I have a 2005 Prius and all was fine for first two months.

Then we had a some snow and pulling off one morning to go to work, the "slippery road" light flashed up as the front wheels tried to get grip and went out of sync. - Not a problem normally as the car is designed to do this...

The trouble was, all the other warning lights then came up and have been on ever since.

So I now have ABS VSC and the two Exclamation warning lights on all the time and obviously have no functioning ABS / traction.

I hoped this was just a logged fault on one of the computers and tried all the various ways shown on this Forum of getting rid of them. Battery off for 20 mins - no luck - connecting the terminals Tc and CG of DLC3 to go into diagnostics etc - no luck.

Eventually I spent £170 on a V-Scanner that has Can Bus compatibility to be able to talk to the ABS/VSC computers.

I was hoping to just clear the fault and be done.......

The codes I got were and are -

C1203 1/3
Engine Control System Communication circuit Malfunction

C1345 2/3
Not Learning Linear Valve offset abnormality

C1392 3/3
Un-Correction of a zero point of the stroke sensor

I can sometimes clear these faults (but mostly do not clear), but all this does is cause the lights to flash the next time I drive and then go solid again on the next drive.

The only thing learned from this is when flashing (more like strobing one on at a time) the slippery road light comes on (even when on a straight road) and the engine has now power for about 10 seconds. (Again what the car is designed to do - but why is it doing it?)

I assume from this, that something is telling the car that the wheel is spinning when it isn't causing (like the original fault) the lights to come on and log the fault.

With this info and reading about this a lot on this forum, I looked at the ABS speed sensors on both front wheels.
They both read 1500 ohms approx and show readings on an oscilloscope. (As well as logging separate faults on the V-scanner of ABS speed sensor disconnected) - so I conclude it's not these causing the fault?

If anyone has any idea with this, it's appreciated.

I'm looking at selling the Prius, as we're buying a house and need the money from it's sale asap.

If I get no luck, I will be taking it to the shop but am nervous of getting charged $1800 plus for computer changes that are not required if I get a mechanic who doesn't know what he's doing

Thanks for listening guys...... Hopefully someone has the missing piece of the jigsaw...

 

No warranty 110K Miles.
I've got it booked in with Toyota on Wednesday, they managed to squeeze me in between all these recalls.
£45 for running the diagnostics.
Hopefully it's not the skid control ECU - why would a computer just fail? I can understand a sensor giving a funny reading, but can't see why a computer would just fail?
Fingers crossed, I'll let you know, thanks for the responses anyway

 

As I thought!!

Rear ABS speed sensor according to Toyota.

An extra fault came up at Toyota that didn;t come on my V-Scanner.

C0215 - Rear Left ABS sensor
All the above warnings also came out which proves that the V-scanner wasn't making it up, but not sure where to look in the menus for this other message otherwise it may have saved me a trip to Toyota - Though I must admit they were very professional.

I've got a sesnor on order from the U.S as about 50% cheaper - delivered express by USPS.

Now for the big question, has anyone changed a rear ABS speed sensor on a Prius?
It looks like it goes in the centre of the hub.....
Anyone know how to change one before I get started ripping it apart ?

Cheers in advance!!

 

Changed the Sensor - Exactly the same problem occurs

Any one know how to change an ABS computer on one of these?

Anyone know where it is ?

Thanks.

 

Thanks for the info guys, I didn't think about getting them to do a drive diagnostics..

I will get a quote for this and fingers crossed will get it sorted.

I read somewhere else that it's possible to reset something on the skid ECU , so maybe it just needs resetting, or needs to re-learn something with the new sensor in ?