first time here and I was hoping some of the Gen 1 experts out there may be able to help me. It all started 3 weeks ago when I brought my Gen 1 in to have the windows tinted (it's a solarium!). When I got the car back and tried to leave I got the discharge warning light even though the car would start. It would lurch forward and rev up without going more than a few miles per hour. After 1/2 hour of running and some help from a nearby auto shop who reset the fault codes, I was able to cruise home. I can only assume that the shop left the car on while they did the work and ran down the battery which was able to recharge itself after some time running. After taking some voltage readings from the 12v battery and determining it was on its last legs, I decided to replace it with the OEM Toyota one. Then we were on the way up to Big Sur last week and the hybrid battery system warning light came on and the car literally stopped as we pulled into the campground. Again, it would move forward in a very reduced manner but not enough to get us home. I pulled the negative cable from the 12v battery thinking it might reset the code, which it did. The camp host was nice enough to put a trickle charger on the 12v battery because I just could not think of anything else to do - a $600 tow was out of the question. We got it charged up to max, put it in a day later and left the following morning. Managed to get it to the Toyota dealer in San Luis Obispo driving at 45 mph with a lot of unhappy folks behind us. They take it in and can't find anything wrong with it telling me that I cleared the codes when I unhooked the 12v battery. We were able to make it home the next day but there is definitely something still wrong with the car despite no recurrence of warning lights. There seems to be a loud whirring coming from the area of the engine compartment where the inverter is. The fuel economy is much worse than before and the hybrid battery does not seem to want to offer much assistance, especially at lower speeds when I used to be able to drive it in all-electric for a good distance. The car has 120,000 miles on it and I know the previous owner replaced the hybrid battery pack at 80,000 miles in 2010. So, I don't think that's the problem. I replaced the plugs and cleaned the throttle body yesterday and that did not seem to solve it. I am thinking it is probably something electrical like the inverter or ECM. But I am kind of flying blind without indicator lights. Any ideas?
That sounds indicative of a bad inverter water pump and the inverter is overheating. Take a look at your inverter coolant reservoir and see if you see any turbulence. If not, another sign of a failed inverter water pump. The whirring sound from the inverter area is another sign. If you are a DIY'er this water pump is not that hard to change. You will need to change your coolant also.
I agree with JD. Give us some more info though. Does the car still only go 45mph max? And despite that the dealer said they can't find anything wrong?? Does the car only going 45 max mean all is well to them????? Assuming that's not the case, then the inverter cooling pump is your likely culprit. If you have a bad inverter coolant pump, the car will function normally until the inverter heats up, then it will cease to provide your mg's with power (causing the symptoms you indicated). If you pull over and let the inverter cool down, it should function properly again (provided you didn't allow the inverter to become extremely overheated).
I thought about the inverter water pump but coolant still seems to be circulating in the reservoir. But it does explain why I've lost some electric assist. It also explains why I had the problem in Big Sur - it's very hilly there and I'm sure it was having to work pretty hard to maintain speed/keep cooled. And yes, I asked the dealer to drive the car - the whirring is very pronounced - but I don't think they did. And no, the car will go faster and seems to do much better on the highway maintaining speed. Thank you so much for the replies! I will change that out
If the inverter coolant is moving then there is no reason to swap pump, unless it is making a lot of noise - you can easily determine that by opening the hood, turning the car "ON" without starting the engine and listening immediately behind the driver side (left) headlight. You can also put your hand on the black plastic pump and hoses. There might be a minimal vibration, barely noticeable in normal operation. If yours is making a lot of noise and/or vibration, then it is good to replace it, before it fails. Another version of lack of power problem is when the transaxle develops a shorted winding, then the inverter will limit its output and thus there will also be hardly any "electric assist". Yet another way to lack assist is when the hybrid battery is worn out, then the battery management will notice the large voltage swings and too large difference between modules, so it will limit current drawn from the HV battery. At times it was so bad that I could not even drive backwards, because the system did not allow the motors to draw enough current to do that. And the engine was racing to deliver enough electricity, even while standing still. All that was solved when swapping HV battery, although a long slow charge of the HV battery allowed it to run normally for a short while - until some charge was taken from the HV battery and bad modules started dropping like rocks. But do start with the simple checks like opening the cap on the inverter coolant reservoir next to the inverter in the center of the engine bay. look down into the reservoir and you should see a "waterfall" of coolant from the small front section into the remainder of the reservoir, due to the coolant flow. If you see that then the power reduction was *not* due to a coolant problem and you need to search further - if needed after taking the car for a spin to get it to drive no faster than 45 MPH and then verify *why*...
To which I would add, get a Prius-aware scanner to read the vehicle metrics. There are half-dozen control computers more than willing to report what is going on and a Prius-aware scanner can read them out. Bob Wilson
Run2live, The car's not currently showing any codes right? I know you said you cleared the Master warning light but does this car have any indicators like Check Engine Light, TOD, etc?
The symptoms you describe are those of a failing hybrid battery. My experience is that the hybrid battery life is about eight years. Do you know the age of the replacement battery. My 2001 needed a new battery in January 2009 at 197,000 miles. My sister-in-law's 2001 needed a battery replacement in September 2009 at 97,000 miles. I think that is why Toyota changed the warranty in 2004 to eight years from ten years. Bob Edwards 859-509-3872
Bob, I don't think we have enough info to make that call yet. A failing battery wouldn't give those exact symptoms without TOD, turtle and CEL would it??? It sounds like a failed inv coolant pump but, not enough info to even make that call at this point.
I'm not even sure it sounds like the pump to me yet, with the OP reporting visible flow. If the pump is the source of the loud whirring then either it's going out or there's trapped air there, but it should be really easy for the OP to check whether that's where the noise is coming from. If it's not ... hmm ... I really can't think of anything inside the inverter that would make a whirr sound, unless high currents at various frequencies could be wiggling something that's loose. I'd first guess the sound's from somewhere else. If it were me I'd start by querying the computers as step one, and we don't have any of that info yet. If any codes are stored that's essential information naturally, and even if there aren't, inverter temps, motor temps, battery temps, module voltages, etc., would all be helping to fill in the picture here. It's a pretty indistinct sketch at the moment. -Chap
