Check Hybrid System message came on during a short trip while jiggling the ODB-II connection to m...

I would start by reading the trouble codes that were logged when that happened. I'll guess they will be Uxxxx codes indicating a communication disruption on one of the networks. Which one will suggest which pins of the diagnostic connector will be involved.

In the past, it has not been unheard-of for certain scan-gauge-type devices to try to autodetect what they are talking to, and put probe signals on certain circuits that different cars use for different purposes, and disrupt communications in the Prius. Sometimes the device will have settings to disable autodetection and lock it to using certain protocols and pins only. Sometimes strategically snipping a wire or two in the cable will do it. (Linear Logic, the makers of the ScanGauge II, had a separate cable for the Gen 1 Prius that you could have them send for free if you needed it. Gen 1 was pre-CAN.)

Not knowing more about the Ultragauge specifically, that's about all I've got.

-Chap

 

I had a ScanGuage connected to the OBD port on our 2010 for maybe 3 years when I got "check hybrid system" message, coupled with a noticeable "returned to defaults" feel to the brakes. Took it into the dealership, and they reported brake communication related codes, dismissed them. There were a few more occurrences over the next couple of years, and repeated dealership visits to dismiss.

The last time, coming up on 2 years back this August, I was with the mechanic. He had a techstream laptop hooked up, and noticed that when he wiggled the OBD connection he would lose signal momentarily. He suggested I try leaving off the ScanGauge.

I've done this since, with no further problems, so I would say that was the probable cause. At any rate, disconnection of the SG has been a good solution so far.

 

Yeah I miss coolant temp, and a few others. But I got over it.

 

Ignorance is bliss.

 

My ScanGauge II is constantly plugged into my Gen 3 and has never caused the least problem. Before that, it was in my Gen 1 for six years and never caused the least problem there, after I got the Gen 1-specific cable for it that prevented it from trying to talk to the airbag computer as if it were a CAN bus.

I guess what I'm saying is, these "glitches" aren't eternal cosmic mysteries, they are typically deterministic behavior of machines, and once found and solved, they stay solved.

-Chap

 

Mine was constantly plugged in too. Could be fine on some problematic on others. Anyway, its something to try changing, see what it does.

 

Sounds like a lost network communication fault on the canbus. The Ultragauge's partial connection might have stopped the signal from other modules on the canbus from talking to the hybrid control module. This would set a communication fault code in that module that the ultra gauge couldn't read but could reset. The hybrid module needs to be able to talk to the battery controller and the engine module, if it can't, you get that message.

I had a Pontiac once that would occasionally loose contact with the instrument cluster, and it would set a U code dtc every time. It was a loose ground connection.

 

Talking with the Service Manager about our case, he was favouring expressions like "communications problem" and "missed handshake". Which is just what I wanted to hear. The codes in our case were brake related (and there was the return to defaults brake behaviour) and the LAST thing I wanted to hear was "new master cylinder" or something like that.

And yeah, about 21 months post ScanGauge disconnect, no further problems. I'd love to have the ScanGuage reinstalled, but it's no big deal. I suspect the weight of the connector was stressing something, being on there constantly. The OBDII port is likely designed for temporary use, typically with the car stationary.

Plea to Toyota: at least put a bloody coolant gauge in there, c'mon.

 

Connections are the least reliable part of any modern electronic device. All you need is a little grit or oxidation of the contacts in the connector to cause an intermittent signal that could put glitches onto the bus. And those kinds of problems are the ones that get more likely with the passage of time, as vibration, thermal expansion and wear take their toll.

 

Not that it has any direct bearing on your problem but............
Don't those gauges stay powered up all the time that they are plugged in ??
Seems like I remember that they could sap the 12 V battery if the car sat unused long enough.
And that might not be very long IF the battery is nearing the end of it's life.

 

I just started a thread in the Tech section on this.

I tried using the Gen 4 codes in my 2016 Prius c and they did not work, however the Gen 3 codes that I tried seem to work OK (Exterior and Interior temperatures and State of Charge). I contacted the Scangauge people this morning, maybe no one has tried any of these codes on a c yet.

 

bah, double posted, sorry. Stupid PC