Prius 2002 stopped, no restart, no scanner connect etc.

You'll want to get access to volume 1 (diagnosis) of the service manual. Easiest way will be the $15 subscription at techinfo.toyota.com, as the paper volume seems to be out of print now. You might find a used copy, but at techinfo you'll have all you need right away.

Compare what you're seeing to the "fuel-gauge diagnosis check" under "combination meter system" (page DI-661-1 in my copy, but your year is different so the pages might change). It sounds like you're seeing the first blink pattern (all segments, pattern #1). That would be a failure of communications between the various ECUs, possibly caused by a wiring failure or by failure of the Body ECU or Engine ECU. This isn't a common failure (I've been on this forum since 2008 and haven't seen it posted before), so there probably won't be a lot of threads here to help you ... it'll be a matter of studying the diags manual and using your head. Whatever it comes down to will probably not be an expensive fix.

Don't get started thinking it's your HV battery just because you've heard Priuses have one. That's a common jump people seem to make, but there's nothing in these symptoms that point to it.

If you're using a scantool that isn't known to communicate with all of the Prius ECUs, you probably should get your hands on one that is. You can find threads here about that.

In your case it's possible, even with the right scantool, you won't get information because of the communication problem. In that case, many of the ECUs have an alternate way of displaying codes by blinking lights, which doesn't require the OBD-II bus to work. That's very well covered in volume 1, plus there are a lot of posts in this forum about it.

However, most of the lights that blink are on the combination meter, so the communication issue you seem to be having might block that too. But that would be a useful result; it would tell you something.

The Body ECU has its own fallback where if it can't communicate with the meter to flash codes, it flashes the dome light instead. So I'd go ahead, get a jumper wire, try the test mode, and see what you see. It will probably tell us a lot.

-Chap

 

Once you find the problem, you'll be entitled to the whole pint....

-Chap

 

If the OBD bus is not working:

• check fuses - not just inspect but ohm them out
• use 'flash' techniques described in the diagnostic manual to check each ECU
• reseat connectors - inspect and reseat

I hope it is not a broken wire in the harness . . . those are the pits!

Bob Wilson

 

I don't think Bob meant "flashing of the ECUs" in the way sometimes meant (storing new software in their flash memory) ... just telling the ECUs to flash lights to tell you what's going on. That's easy, you put one jumper wire between the Tc and CG pins at the diagnostic connector, turn the key ON, and (normally) lights all start blinking the codes from their assigned ECUs, all as described in the various volume 1 chapters where it says "in case of not using Toyota hand-held tester".

In your case, with a suspected comm problem, the blinkage might not all happen (because the lights are mostly in the combination meter, and the other ECUs need to communicate with it to make the lights blink). The Body ECU has its own fallback method: normally it blinks out its codes on the door-ajar light, but if it can't contact the combination meter, it blinks the dome light instead.

If it were me, I think I'd start by trying to get codes before trying to dig out fuses, clean ECU connectors, etc. Even uncovering all the ECUs in the car is a chore, and knowing what codes you get (or can't get) could narrow it in a way that saves you a lot of time.

-Chap

 

So are you saying you replaced the pump twice?

Russ

 

Im experiencing the same type of issue, while driving my car shut off and didn’t turn back on. The red triangle popped up and saying main battery. I left it for 10mins or so turned it on and even drove it around the block. Idk what is the issue with it ! Anyone please help !!!

 

Check your inverter coolant reservoir with the ignition on but with the engine not running - don’t crank it. If you see no turbulence, then you need to replace the inverter pump just like the original poster did. The system will shut the car off to prevent the inverter from overheating. Good luck.

 

Yes, and it has been hot for the past week, so this issue would be more likely to raise its ugly head. I'd probably just plan on
acquiring a new inverter coolant pump.

 

FWIW: any owner of a Gen I Prius with more than 200k miles should consider replacing the inverter cooling pump (part #G9020-47022, about US$120) when convenient, as a preventive maintenance item. As many posters have indicated, this is a "can't get the car to go at all" failure mode. Consider this: assuming an average speed of 30mph, 200k miles is 6700 hours of operation. Computer hard disk drives have a 50% failure rate by 10,000 hours (the B50 Weibull life, or "average" life") so... how lucky do you feel? I have had two inverter cooling pumps fail at about 250k miles (and 15 years), fortunately in situations when limp-home was an option. Of course, keep the operational old one as a spare, "just in case"...

 

I have a 2003 that did basically the same thing. I went to pick up my daughter & the car was running fine I waited for several minutes & decided to turn the car off to wait instead of leaving it running. When she came out to the car it would not do anything everything was gone! I had intended to fix it & even bought a used inverter /converter unit since that was what I thought it must be. Battery was showing good & the one in the truck tested where it should be also (dealership assured me it was the small battery so I tested the voltage) I had just had the steering column nut changed & the steering got very bad afterwards so Toyota ended up changing the rack & pinion. I have not been able to even attempt to fix it because I can not lift the unit & now my son-in-law who was going to help me can't due to an accident at his work. I loved the car but it has been sitting for a while now & there is no way I will ever be able to do the work required even if it is the fuse & the pump needs to be changed the dealership is 45 minutes away & from what I read it would not make it that far without stopping again. Just would like some opinions on whether to junk it or see if I can sell it? Which do you recommend. I live in Florida near the Villages. I really hate to junk the car as I loved the way it drove & the mileage it got but no one around here will work on the hybrids

 

When you say you can't lift the unit, are you talking about the inverter assembly? Maybe that isn't what you need.

There are posts about how to find out whether your cooling pump for the inverter is working ok. If it isn't, it won't be that hard to lift ... more like the size and weight of a puppy.

 

My book said you had to remove the inverter for that also but I have no way to drain the air from the pump. I do think the pump may be the problem or was starting to go out as I could not see the water bubbling around like it was supposed to but I drove it for a while after I read that that might be a problem so when it totally stopped I assumed the inverter burned out. I am no where near a mechanic but had up until that time with clues online & following the book managed to keep it running with little problems. I most of the posts I had found either did not know or said it was the inverter so I bought another inverter (it is in my shed) but was never able to get it changed. This op is the first I found that said it could be something else. I am not sure which fuse it referred to but will try to figure it out & see if it will come back on long enough to check. Like I said I loved the Prius & would love to get it fixed but even if it is the pump I would have to have it towed to the dealership because I can't drain the air from the pump or at least not the way the book said to do it. Is there a link to an easier way? & if it is noot the pump then I should scrap it?