Overheating?

[aelliott]

Hi, I am new to the forum and I am hoping I am posting to the right thread. About a year ago I had front end damage repair done. I went through my insurance company and they gave me people who did not know how to fix a prius
Now, whenever I travel long distances, especially if it is warm out, I get the Problem screen, the AC stops working, and the engine looses power. But the warning light I get says the breaks are malfunctioning. If I stop for about 10 min, I can drive again for a while but the problem screen doesn’t go away for a couple of days.
I took it to the dealer and they say they can’t find anything wrong. But they also said the warning code was not one they ever saw before.
Does anyone know a good Prius mechanic in Maryland?

Thanks.

[Patrick Wong]

What DTC was logged by your car? I suggest that you find another Toyota dealer for diagnosis.

Based upon your symptoms, I would guess that the inverter is overheating. When this happens, the DC to DC converter within the inverter will shut down and this will cause voltage on the 12V bus to sag. The skid control ECU is very sensitive to voltage fluctuations and will cause the BRAKE and VSC lights to come on.

Inverter overheating can be caused because the cooling system was not purged of air, or because the inverter coolant pump has failed.

Here's what you can do to narrow the problem down: When the car is READY, look at the inverter coolant reservoir (mounted on the inverter in the space between the engine and the inverter.) Do you see turbulence in the fluid level? If yes, then the pump is working. If no, then you might have air in the system or the pump is not working.

If no fluid turbulence, then place your head near the driver's side headlamp and listen for the inverter pump when the car is READY and the gasoline engine is not spinning. This sounds like a aquarium pump and is located immediately behind the headlamp assembly.

If you can hear the pump that's good, but if you can also hear air bubbles then you'll know there's air in the system. If you can't hear the pump then this must be replaced. Good luck.

[northwichita]

Agreed with Patrick, just to add a Dealer missed the fact my inverter pump was out, though it possibly could have been in my case that the problem with the inverter pump was intermittent.