Hi, this warning light (red car outline with exclamation mark through it, bottom right of display) has come on along with others (VSC , brake warning & Catalytic converter) which have now cleared, it was a very hot day. The red car remains on & I have lost all hybrid function ie seemingly no hybrid assist or regen braking; no energy flow arrows; no air con etc. Im wondering if it's related to the inverter coolant system, & wanted to check the coolant header, which is described as being a separate tank from the main engine coolant expansion tank but I cannot find a separate tank. Does anyone know if there is a separate header or if not a cooling issue, what else could be causing this fault. Thanks, Chris

The inverter cooling system uses a separate part of the radiator at the bottom so you won't see it. The system involves the radiator plus the cooling pump. The pumps do go faulty, I replaced mine at about 65k miles. If the petrol engine runs you can check if the pump is working by taking off the inverter cooling filler cap which is the one on the right side of the top of the rad. With the engine running there should be some movement of the coolant usually you will see it going up and down in the filler neck. You should also check if there is sufficient coolant in the system. Anyone with a hybrid should consider changing the pump anyway as a precaution as failure is not uncommon at a longish mileage. It is not complicated. Ensure you fill up with Toyota Pink coolant which is non conductive electrically.

Thanks Paul, the expansion vessel is near minimum level so i'll get some pink coolant & check the inverter side flow as you suggest.

Wow, I was just coming on here because I have the exact same problem! @PaulE do you know the official part name for the pump?

Is it this by chance?

Edited 17 hours ago17 hr by alphardoh
added link

The Toyota diagram ref is 16290A - PUMP ASSY, WATER W/MOTOR & BRACKET

There are several part no.s as they kept changing them for the same part and updating the part nos. You can usually get them on Ebay.

These are the numbers from Amayama. Toyota Alphard Parts - Toyota Car and Auto Spare Parts Online - Genuine Online Car Parts Catalogue - Amayama

G9020 58010 /58011/ 58012. However I ended up with a spare one after the post office cocked up my delivery and this is

G9020 28022 (see pics) Double check your vehicle against any you see for sale.