Hymotion "flashing LED" error codes

It hasn't happened much to me lately because I have learned to avoid a few things.

Don't start the car while it is plugged in.
Don't let the battery drain while in accessory mode.
Don't play around turning the Hymotion battery off and on, just leave it on full time.

If you do get any flashing lights, try just turning the car off for a while and plugging it in to recharge. I think this has the effect of forcing the Hymotion battery to start a new communication attempt with the Prius computer.

These are all just based on a few weeks of experience. This is not from Hymotion or anything. I will be back at my local installer (Green Car Company) this weekend. I will try to get permission to post what each of the flashing codes actually indicates. We have the codes and I have seen them. But I don't know if Hymotion wants those out in the public yet.

 

I have never seen the flashing triangle. I did have flashing led once right after installation. Did noy even know to count them.
Like Peakoil I never turn of the switch for the pack. I've only tried to start the car once when plugged in and nothing happened. I have not worried about accessory mode since I figured my 12v battery is fairly new.
renewablesnow, sorry to hear you have to make the return trip to Westboro. I assume the pack change will be quick vs the original install. Let us know how the change works.
Chris

 

SaucyRed, if you want to meet and show me your problem, let me know. I'd like to try to troubleshoot this error with you. I live only a few miles from you.

 

So, I got my first flashing error code. 13 flashes I think and my car gave me the red triangle of death and disengaged the transmition. I pulled over, powered off/on and was able to go, but still had the triangle. I scanned with my scangauge and it showed a 000001 error. I don't know what that is, but cleared it. The pack would not work for my drive in, but at lunch it was just fine. Any thoughts on the 13 flashes or the 000001 error code?

 

I have noticed that I have issues when I spend too much time in accessory mode. Have you noticed when you do a quick press on the Start button, then you try to shift into Drive, but it only goes into Neutral. You have to stop and restart the car to get it into Drive.

This has been the type of thing that has caused a communication error for my Hymotion to communicate with the Prius.

So now I am very careful when starting the vehicle to have my foot on the brake and fully press and hold the start button.

Another scenario that has caused problems is trying to start the Prius while it is plugged in recharging.

Typically the fix for all of these flashing codes is to do one or more of the following:

1) Turn off the Prius for a few minutes
2) Plug In the Hymotion battery and allow it to recharge
or
3) Both of the above

 

Hymotion is not sharing what the codes mean. I was at their facility outside Boston last week and was told they dont want early adopters attempting to troubleshoot and repair the L5 if we know what the 13 flashes mean. I had the 13 flashes happen on 4 separate ocassions. Every time the L5 stopped working. I then got the red triangle and was encouraged to disconnect the wiring harness connecting the L5 to the car. Erin Scott gave me the tour and I was shown the production floor where they build the L5 units. It was quite impressive.

 

The only other solution is to replace the battery. And I have heard from two people who have replaced the battery that they still have the same error.

That leads me to believe it is not the battery. It is some key behavior that users should be careful to avoid.

We need Hymotion/A123 to give us some "best practices" on what to do when this happens and what actions we should avoid.

 

I guess I'm lucky because I have not had any more issues with mine.

How about we start documenting the exact steps you take when you get the error codes and the steps you take when you don't get them.

For an example here is what I do most days.

I first unplug the power cord. I then unlock my locked car with my hand through the door handle because I have the smart key. I then step on the brake and press the power button. Then I turn on the battery. Then I release the parking brake, put the car in drive and take off.

Some days the battery may all ready be turned on. Some days I will start off in accessory mode so I can play with my computer for a few minutes. Sometimes I also go immediately into EV mode after turning on the car because I still may need to play with my computer for a few more minutes. The AC is always turned off when I start the car.

If I was getting these error codes I would start documenting every last detail to find out what the cause was.

 

The main difference that I have in my standard operating procedure is that my battery is always on when I start the Prius. I don't have to use my parking brake.

Because I live in a neighborhood at the top of a hill, declining that hill creates a lot of regen energy. While I start with my battery on, once I am sure I am in EV mode, I turn off the Hymotion battery as I approach the downhill portion. This drains my stock battery to 5/8 SOC. By the bottom of the hill I am normally at 7/8 or 8/8 on the stock battery SOC. Then I drive some more to get that down to 6/8 SOC, then I engage my Hymotion battery.

This activity going downhill gets me about 2 miles before using any of the Hymotion battery energy. Doing this has never caused any of the "flashing LED" errors, so I believe it is safe for users to turn the battery off and on with no concerns.

 

So more on my scenario. I started the day with a full charge and the battery off. Drove about 1/2 mile on the stock battery with the hymotion off. It was off when my check engine light came on at 45 mph on a slight incline. Lost power to the drive train and had to pull over/cycle power to go again all-be-it with the check engine light still on. Cleared that at my next stop light with the scangauge after reading the 000001 code.

The other time I had a check engine light, though I didn't have a flashing LED code with that instance was driving in EV mode (I have the coastal tech switch which uses a 2 second hold on the cancel cruise control feature). I was driving EV at about 30 mph on a slight incline - same prius symptom of drive train dropping out of gear - having to pull over and cycle power. The scangauge read all 0s for that one and I cleared it.

I emailed Erin today with my issue, beep code and also reported my 20-25 mile average range. She is forwarding to their tech support team who are supposed to get back to me in a day or two max.

 

Max, if you are driving with the Coastal Tech switch and the Hymotion, that could be the source of your problems. I would remove the Coastal Tech switch and see if that resolves the conflicts. From what I have heard both use Pin 27 at the same time and this can cause issues.

 

I'll remove it. For the install, They just tapped the coastal tech wire and said they had seen and done this before.

 

Sorry I haven't posted in a few days. I did get a call within 24 hours (SLA was 48 I believe) from an A123 battery engineer in Canada. He was very knowledgeable and spelled out 3 scenarios that could reflect my battery performance:

1) I am a very efficient hypermiler. With pure EV or close to, we should only expect 15-20 miles on the pack according to this engineer.

2) My pack is not YET fully balanced. He stressed yet and this seems to align with some of the comments that battery performance improved with use and a series of charge/discharge cycles on the battery.

3) There is something wrong with the pack, possibly a section of cells which are in error not accepting a charge or discharge.

I have had my pack over 3 weeks and use it daily (2 charges a day when I can). I've only had one flashing LED error which he said the 13 flashes indicates a communication error between the battery and the CAN bus which is serial in nature and any of the connected devices can cause this to occur. He was not concerned about the one occurrance, but mentioned I should continue reporting any of these should I get them. In my 3 weeks of daily use, I have not seen a discharge cycle last over 30 miles. I average about 20-25. My driving is mostly freeway at 55-60 miles per hour. One thing he mentioned there was a suggestion to increase my speed stating that at higher speeds there is less draw on the pack and more on the ICE. I will try a few days at 65 and see what changes.

Long story short, he asked me to monitor another couple of weeks and if my range does not improve, call back and they will send me a data logger to attach to the OBDii port so they can collect data about my driving habits and the pack performance.

I continue to be very satisfied with my hymotion experience - their customer service has been excellent for me. I'll keep you posted on my range improvements or lack there of and if I proceed with the data logger and futher investigation.

 

It happened to me today, no other console displays. First time I have noticed the flashing LED (13 BTW) The L5 did not engage and the car ran as stock. Switch was still in the on position. I did have my SGII with VLT programmed and it was 13.9 at start and 13.8 during the drive. The LED was solid when I climbed into the car.
Things that were different than yesterday. It was warmer 44f ambient, 20 degrees warmer than yesterday. It was also raining steadily, the car is garaged, but increase in humidity. The biggest thing is during the day yesterday I did a partial charge to give me enough juice for all the trips I needed to make. I did remove the charging plug while the brake lights were still on. The car did work properly for the remainder of the night. Then I plugged it in for a full charge and started today normally. Maybe the L5 got confused with a partial charge. I have done full charges during the day between drives. I don't usually cut a charge cycle short. Hope this helps.
Chris

 

Do you keep you SG plugged in all the time? If so you should be able to view the voltage before you turn on the car. If you leave the SG plugged in and have it on the gages when you turn off the car you can press the button in the lower right to turn on the SG and it should still be on the gauge screen displaying the voltage. This way you can check the voltage before you start your car. This will allow you to see the actual voltage of the battery. the 13.9 volts is the charging voltage and not the actual voltage.

 

I agree with TheForce. I am watching Voltage closely on my ScanGauge. If during the startup procedure the 12 volt battery is low (less than 11.0) that can be the triggering event for the LED flashing error.

After you have driven you car for a few minutes, the voltage will be back up to normal. If you stop your car for 5 minutes and allow it to reset, the LED flashing will stop.

It has not happened to me for almost a month. But it briefly happened yesterday. I stopped to get a Coke and by the time I was back to my car everything was fine again and Hymotion worked normally.

 

Good to know. Thanks guys. I have not run into this issue again and still have not removed my coastal tech EV module.

 

I did not know that. I read the forum late last night and checked this morning. 11.7 dropped to 11.5 in ACC. While starting it dropped in to the 10s but quickly went to 13.9. Thank You for the information. I still think my cause was the partial charge. May have to test that again too.
Chris