I was driving my NHW11 in the hot Australian sun this afternoon when, about 30 minutes of pleasant and unhurried driving, I got the dreaded 'hybrid system error' message: I was able to quickly pull over (in limp mode) and park in a shady spot. When I popped the hood ('bonnet', as we call it), the metal inverter cover was very hot, but there was no visibly leaking coolant, and the radiator was not too hot. I let the car sit in the shade for 15 or 20 minutes and when I started the car, got the message again. Before the car threw the message, I did notice the red temperature lamp was on, but a few seconds after noticing, it turned off. When I pulled over, I remembered also that there 'used to be' a noticeable pump or fan noise that would cut in and out, but I realised that I had not heard the sound in a few weeks. Ironically, I had that morning been on the phone to a local hybrid mechanic, organising to get the car serviced, as I suspected the engine needs tuning, and also wanted the other components checked! As it was a Friday afternoon I was not able to organise a tow so decided to leave my Prius parked in the street and was able to get a ride home. I can get the car towed to the mechanic on Monday morning (at a cost of about $90) but the mechanic seemed to imply that it could be drivable and that this may not present a problem. It is about a 10 minute drive. I could do this late at night when there is no traffic, so I could drive slowly with regular stops and monitor temps. So there is my dilemma. Do I wait until Monday (and leave my car in some strange neighbourhood!) or try driving it to the mechanics over the weekend? Based on the symptoms I described, does anyone have a clue what the likely fault is, and therefore whether it could be damaged by further driving? I'm just totally in the dark and trying to weigh up my options. I'm tempted to just pay the $90 to have it towed and not risk further damage, but if consensus is that another short drive won't hurt, I'll consider risking it. Many many thanks, Jeremy
Hi Jeremy, Certainly check at least that the coolant for the inverter isn't low (should be between the two level marks at the small reservoir next to the inverter) and that the pump for that coolant is doing its job (whenever the key is ON, you should be able to see the fluid level higher in the front of that reservoir than the back, with a little waterfall going on). If the problem is the pump, the pump's not very expensive, but overheating parts of the inverter can be a risk if coolant isn't circulating. -Chap
I agree with Chap (as usual). Check the pump like he said. It sounds like its not circulating and therefore, not cooling. If it is not circulating, It is still safe to drive for short distances. Esp if it is late at night or early morn but def not the heat of the day. 10 minutes of driving should be ok.
OK, cheers guys. I will head back today to check it out. I have borrowed an OBDII adapter to try to scan for error codes too. If everything indicates a coolant pump fault I will consider driving it over myself. Thanks again. If anyone has any more input it's more than welcome.
Hello, I went to visit my car today and had a look at the ECU codes using an OBDII scanner. It showed a P3130 error code, which I understands pretty much confirms a dud coolant pump.. I actually decided to 'clear' the error code from the ECU so that I could try driving a short distance. After clearing the code, the car ran fine - actually better than ever - and I did a slow once around the block. After getting back and having the car idle for a little while the inverter lid was pretty warm. I'd say 60C. Almost too hot to touch. Coolant level is OK but does not appear to be flowing (no 'waterfall') and I can't feel it going through the hoses. Question: Now that I have 'cleared' the code, will the car bring the error up again if the same condition (excess temperature?) arises? In other words, if I do drive the car to the mechanics, can I assume that the car will protect itself from further damage by throwing the error if it gets too hot? Or is it more of a 'silence alarm' type operation .. Many thanks Jeremy
Jeremy, just curious, in Australia do you have something like AAA like we have here in the U.S.? (AAA is a membership organization you can call 24/7/365 and they will tow you, jump start, change tire, etc. I have the plus membership for $79. which means I can get towed anywhere for 100 miles twice a year if the need arises.) When I read about you having to leave your Prius in an unknown neighborhood over the weekend, this made me think of AAA. I am glad I am a member, let's just say it is "peace of mind" whether I use any of the benefits or not. Something to think about when driving an older vehicle.
yes we do - the organisation is called the RAC and basic membership is $96/year. I actually planned to do this and rang up and gently asked how soon the coverage starts after signing up. I spoke to two people and they were both very cagey, they obviously don't like people joining then making a claim. But their terms and conditions are pretty clear that standard coverage (towing) for the plan starts after payment is made. Extended coverage (for taxis, accommodation etc) starts 24 hours after joining, but there's noticeably no clause like that for the standard coverage. Question: Can the classic prius be safely towed (~10km) on its back wheels? Thanks Jeremy
Good Question! Actually not sure. Whenever I have had to use AAA (for other vehicles not my Prius) they have come with a flatbed. Loaded the vehicle on top and then transported. No towing!
Ended up driving it to the mechanic's workshop late at night - I used Torque and a bluetooth OBDII adapter to chart the MG1 and MG2 inverter temperatures as I drove and was able to keep them down by slowing/pulling over. The max they hit was about 95°C/98°C respectively, averaging about 80°C.
