check engine, (!) and VSC light

[aanimate]

Was driving yesterday and suddenly triangle, check engine, (!) and VSC lights came on. I stopped and restarted my 2005 prius, but red triangle and check engine light still on. Car drives the same, no problem at all.
My tank was half full, I pulled to gas station and filled the tank, and the lights went away.
So I thought that I didn't put the gas cap tight enough.
Today I was driving home and the same thing happened, all 4 light came back. I filled my tank again and lights went away.
Does anybody know what the problem is. Could it be a bad gas cap?

[Blegate]

Originally Posted by aanimate

Was driving yesterday and suddenly triangle, check engine, (!) and VSC lights came on. I stopped and restarted my 2005 prius, but red triangle and check engine light still on. Car drives the same, no problem at all.
My tank was half full, I pulled to gas station and filled the tank, and the lights went away.
So I thought that I didn't put the gas cap tight enough.
Today I was driving home and the same thing happened, all 4 light came back. I filled my tank again and lights went away.
Does anybody know what the problem is. Could it be a bad gas cap?

Codes... you need to get the codes generated by the car's computer. A toyota place can do this or if you know someone who has a scanguage.

Sorry

[Patrick Wong]

Originally Posted by aanimate

Was driving yesterday and suddenly triangle, check engine, (!) and VSC lights came on...Could it be a bad gas cap?

I suppose you know that when you tighten the gas cap, you need to tighten to get at least one click? Also, when the cap is removed, you can look at the black rubber O-ring to see if it looks damaged.

However, even if the cap is bad, that would not cause the master warning triangle, (!), and VSC lights to come on. The latter two lights indicate a brake problem which might be related to the 12V system. Maybe your inverter coolant pump has failed so your inverter becomes slightly overheated. This causes the DC to DC converter voltage to sag and the skid control ECU turns on those warning lights. Then, when you stop for gas, this gives the inverter a chance to cool down and restores normal operation of the DC to DC converter temporarily.

I suggest that you visit your Toyota dealer very soon to have the DTC retrieved to confirm or deny the above.

[aanimate]

Originally Posted by Patrick Wong

I suppose you know that when you tighten the gas cap, you need to tighten to get at least one click? Also, when the cap is removed, you can look at the black rubber O-ring to see if it looks damaged.

However, even if the cap is bad, that would not cause the master warning triangle, (!), and VSC lights to come on. The latter two lights indicate a brake problem which might be related to the 12V system. Maybe your inverter coolant pump has failed so your inverter becomes slightly overheated. This causes the DC to DC converter voltage to sag and the skid control ECU turns on those warning lights. Then, when you stop for gas, this gives the inverter a chance to cool down and restores normal operation of the DC to DC converter temporarily.

I suggest that you visit your Toyota dealer very soon to have the DTC retrieved to confirm or deny the above.

Thanks so much for the help.
I am bringing the car to the toyota dealer tomorrow.
The thing is though, even I if don't drive the car for extended time( 4-8 hours) the two lights will come on, and to make them go away I just have to put the gas in.
The other interesting thing that dealer told me after I describe the problem is; sometimes the lights related to a loose fuel tank cap can come back (even though they went away for a while), so I need to drive it couple more times to make it go away.

[richard schumacher]

I think Patrick is right about this. Your weather is not very hot, so the inverter gets just warm enough to panic, and then it cools down enough while you're buying gas to clear itself. See a dealer. If your 60 month/60K miles warranty is still in effect the inverter pump replacement will be free.

[aanimate]

Originally Posted by richard schumacher

I think Patrick is right about this. Your weather is not very hot, so the inverter gets just warm enough to panic, and then it cools down enough while you're buying gas to clear itself. See a dealer. If your 60 month/60K miles warranty is still in effect the inverter pump replacement will be free.

As I mentioned in the post before the light still come on even if I don't drive my car for more then 8 hours, that should be plenty for it to cool down.
Anyways I just connected the OBD II tool and it says "no codes found".
Very strange.

[johnjamis]

It is easy to tell if the inverter pump is working. With the car in "ready", just look in the inverter coolant reservoir(next to the inverter). If there is turbulence, the pump is working. If the pink fluid surface is dead calm, it is off.