Dear all, My car is being a terror. Pulled off from the lights to the left today, not hard, and just lost power. It drives in limp mode via the engine only and the P0A93 and P0A94 are what shows up. I believe the 93 ones refers to the coolant pump of the inverter, and the 94 one refers to the inverters in general. Other than getting my Mini VCI thing to work (no driver for it as the cd is scratched, could do with a working link to get it set up properly) to connect to Techstream to read the subcodes. The code, didn't clear and it doesn't clear by disconnecting the battery. I haven't checked it since it's cooled down (assuming it was a heat issue as is suggested). The inverter reservoir is full and has clean pink coolant. It doesn't leak because the level never changes. I can't say if the inverter coolant pump is broken, but the code seems to suggest this. But all of a sudden? Very bizarre. Could anyone suggest what the most likely issue is here? Are there any specific things I can check? Thanks in advance.
P0A94 is a problem with the DC/DC converter (one of the things inside the inverter assembly), and means you get a new one under Customer Confidence Program 23TE03. So whatever you do, don't clear that code before getting to the dealership. P0A93 means that excess temperature has been noted of some parts inside the inverter assembly. That can often be because of the pump, but that's not the only possible reason. If you get Techstream working, you should be able to active-test the pump and make sure that it runs. There's a chicken-and-egg question here. If the pump is actually bad, the overheating could have been because of that, and maybe could have been the cause of the DC/DC converter failing. But if the pump is ok, the excess temperature might have been noticed because the magic smoke was leaving the converter.
Oh, sorry, I hadn't noticed your location. If there is an analogous program in the UK, I doubt it is called 23TE03, and some local research will be needed to find out if there is, and what its terms are.
Its ok. I bet it won't be applicable, I can hope though can't I. If it is, I'll be down there like a shot. Where would I even begin to search for that info?
and sometimes they find it. When I'm looking, I go to nhtsa.gov, which in the US is the regulatory agency to which such things must be reported by the manufacturer, and which makes them transparently available to search without relying on dealers to tell you facts against their financial incentives. Presumably the UK also has such an agency.
So i got TechStream working. The inf codes for the P0A94 are 553 and 557. The P0A93 stayed cleared up and hasn't returned, so it might have been a red herring. I did top up the inverter coolant to the Full mark. And I managed to run the inverter coolant pump, so I know that works. Now the car does still rattle under a charging load but generally it was better. I think I was barking up the wrong tree lately. The car DOES drive albeit with zero relation to the hybrid system (but I MG2 is spinning) and it does seem to want to load up if I'm not too heavy on the throttle. But it'a definately a limp mode. While attempting to clear the code, the engine briefly tries to reintroduce the hybrid system (presumably to charge the battery because it's on 2 bars).,but it instantly fails and brings the fault back up. Even without trying to clear the fault code, it's 'like' it's trying to get back to normal but isn't. How likely is this to be a catastrophic mechanical failure of Torque Damper Plate between the engine and gearbox? Or is is much more lilely to be an electrical issue? I can do any of the checks suggested in the repair manual. God, I hope MG1 isn"t broken. Can anyone offer any futher insights based on the above? As always thanks.
If the code that keeps coming back is P0A94, it's a problem with the DC/DC converter inside the inverter housing. Or is some other code coming up?
So am I safe to assume there's no mechanical failure then? And one can assume it could be a blown component in the inverter with converter housing. Thanks ChapmanF
For each trouble code, there is a whole section (sometimes more than one section, split up by INF code) in the repair manual, that will explain exactly what is detected to set the code, and how troubleshooting should go to pin down what the root cause (which won't always be the same) was. The troubleshooting steps are important, because if you get a code for the Flux Capacitor, say, that won't always mean the Flux Capacitor itself is the problem. The code's Detection Condition might say that an unusually low amount of capacitor flux is what sets the code, and the troubleshooting steps then lead you through how to figure out whether the fault is really in the Flux Capacitor itself, or the flux sensor, or the wiring, or a squirrel nest between the capacitor and the sensor. I'm being vague here about the P0A94 details because I'm looking right now in a big PDF somebody else made of the repair manual, and they just completely left out the full troubleshooting sections for P0A94 codes. This PDF includes the summary chart of all the hybrid codes, so some brief mentions of P0A94 are there, but that's not where the good info is. In the US, because of the Customer Confidence Program, nobody really needs to think too hard about troubleshooting that code, since here it means "go to the dealer and get free stuff". In a part of the world without the free stuff, I would still want to go through the troubleshooting steps before deciding what to do ... and because this circulating PDF file doesn't include the info, that would mean using one of the other means of access to the repair manual, described here: Toyota Service Information and Where To Find It | PriusChat
I've been on the online paid Toyota Technical Repair manual section of that part including the -553 and -557 parts. And they seem to be going through the same checks. I can go through all the checks and then identify the issue. I'll even swap the inverter if I need to. What irritates me more than anything is the weather. I have a drive, but no garage. Very very irritating indeed! Bring on the summer. Sick and tired of the British weather.
Quick update: Second hand eBay Inverter labelled 'G9200-47210' (with big letter K in top right corner of the same sticker, whatever that means) as opposed to my original 'G9200-47180' (with letter A) got my car back on the road. So the original fault has indeed gone and has stayed away so far (only one journey to work so far). I must have been the IBGT's for the DC/DC Boost converter. But now another fault popped up which isn't stopping the Hybrid System, but the 'Eco', 'PWR' and 'EV' buttons don't work, but it's not in Limp mode like before anyway... When I connected everything back up, I heard a little electrical pop somewhere, I thought nothing of it and assumed something to do with having the traction disconnected, but the message 'Check Hybrid System' showed up on the display my heard sank, so I read the fault and it's a P0A84 (I think that was it or similar, either way, the meaning is 'Hybrid Battery Coolant Fan Low' (not working), I guess 'open circuit'? I'm going to be hopeful and assume a fuse blew when I powered my car back up (because of the pop)? So does anyone know from the top of their head which fuse might have blown? I'll check myself later, just not this moment as I'm in work. But yea, I'm back on the road. Yay! Funny thing about this replacement inverter was the coolant pipes on it were slightly angled away towards the corners, they seemed solid and still part of the system, and coolant isn't leaking so far. I guess it was a design change.
There are two separate "converters" inside the inverter with converter assembly, and the Toyota names make it easy to confuse the two. They consistently call one the "DC/DC converter" (even though that's what they both are), and call the other one the "boost converter", even though that one is in fact bidirectional. So it's important to know which one each name means. Reference in the manuals to the "DC/DC converter" always means the simple buck converter from traction battery voltage down to aux battery voltage. That's located down below the main IPM in the inverter assembly. When the manuals refer to the "boost converter", that's the big one that's in fact bidirectional: it boosts traction battery voltage up to 650 for operating the motors, and also bucks motor voltage down to traction battery voltage for regen and charging. The transistors for that one are part of the main IPM, though the reactor and capacitors needed in that circuit are separate parts.
