Radiator flush or not??

Hi Bob,

Yes, if you wish to adhere to the maintenance schedule recommendation, then your next coolant change should be at 80K miles.

 

Thank you for your very quick reply, Patrick.

Another reason to hate the dealers. They basically screwed me out of a couple of coolant flushes. I still have about $100 credit with this dealer. Otherwise, I would find an independent garage.

The dealer I bought the car from was even worse. Every time I took my car to them they scratched the interior or left grease marks on the upholstery. And it took me five trips to get the alignment correct.

When I complained to Toyota Customer "Service" they never even answered my letter. As much as I like my Prius, I will probably never buy another Toyota.

Taking my car in for service at a dealer actually gives me an upset stomach. I am retired and hope to move to a city in a few years where I don't need a car.

Bob

 

Patrick, et al,

Just wonder if anyone has tried the factory-prescribed coolant replacement procedure, which is outlined in Appendix C of Hybrid07 Appendix.pdf at Automotive Training and Resource Site which Patrick suggested. It appears that the limiting factor is the need for a DLC3 tester, which is no doubt expensive. Otherwise, I suppose one could repeatedly provide 12 volts directly to the coolant heat storage pump (assuming it's a 12V pump) for 30 second durations until the system is full. I'd guess that would throw a fault code, though.

 

Hi Rob,

This is my plan. Also part of my plan is to disconnect the 12V battery while powering up the CHS pump via a lab power supply, to avoid error codes being logged.

A further complication is to make sure that the CHS pump valve is open - so I am thinking about disconnecting the 12V battery while the pump is running upon engine shutdown - so that the valve will remain in the position used to fill the canister.

 

Patrick,

Looks like there might be two valves of concern: the coolant flow control valve, and the water valve, which permits hot water into the cabin heater. Wouldn't you want both to be open, or would it be safe to assume that when the water reaches thermostat temp the water (heater) valve will already be open because of the temp setting on the MFD? Clearly the coolant flow control valve is another matter, though. Maybe jumper the relay? Couldn't locate it in the Toyota wiring diagrams.

 

Hi Rob,

Thanks for providing that wiring diagram excerpt. BTW, the CHS pump relay is located in the relay box mounted to the center of the cowl above the engine. I haven't yet figured out how to control the CHS valve.

Regarding the valve that allows coolant into the passenger cabin heater core, my idea is to set the temp control to max high, turn the fan on full, then let the engine run for a while in inspection mode. Hopefully that would fill up the heater core.