[bensemailis]

So, a week and a half ago I got the dreaded “service high voltage charging system” message and a MIL. I pulled the code and of course it was P1fff. I knew my coolant was too low when I inspected the tank. Sadly the closest EV certified dealer is an hour and a half away, and the tech was booked a week and a half out. Not a huge deal I drove my 1 ton truck until today. Drove the volt the hour and a half one way, told them about the coolant tank, and 3.5 hours later the diagnosis is “unknown” they tested the cooling system and inspected for leaks but found absolutely nothing. Now I am out $100 and my time, which I am glad it was only 100, but it still irks me that GM wouldn’t cover it because they could not find a leak.

Been working on cars my whole life, and as far as I have learned, the cooling system is sealed, and going between 1/4 and 1/2 gallon low on coolant would indicate something is amiss. The most frustrating part is I can’t fill the coolant reservoir myself without fear of voiding the warranty.

I am wanting to know what you all think, I have always found the responses on this forum helpful, although have never posted myself. Do any of you think there is a way to refill the tank without leaving evidence of removing the tamper proof bracket? And do you guys/gals think GM should honor the warranty for this kind of repair since we cannot perform a simple top off ourselves?

2012 volt 60k miles

 

[bensemailis]

P1fff not covered by warranty

Had my first real trouble code recently.

Got the dreaded P1fff checked and sure enough my coolant was nearly dry in the tank. The only EV certified dealer is about 1.5 hours away, and I had to wait a week and a half for an appointment. Took it in today, told them the code and about the tank. 3.5 hours later they said they couldn’t find any leaks, topped it off, cleared the code, and now I owe them $100. I don’t mind paying for service when it ia something I can’t do on my own, but the stupid tamper resistant cap makes this $100 I don’t feel I should really have to pay.

What are your thoughts on this? I have always found the feedback of this community very helpful.

2012 volt 60k miles

 

[Steverino]

It's called coolant boil-off and evaporation over time. The coolant will very slowly drop over time and if not topped off will eventually run dry. I'm not sure about later years but it definitely happens with 2011, 2012 Volts. Hopefully they refilled your car to it's correct level, at the top of the black sticker toward the top of the tank.

If the car has been regularly serviced by the dealer, they should have been topping off as needed. If you were doing your own, well then that's your job. If the dealer was doing it and you saw the level low, you needed to point it out and have them do their job (yes, should not have to but...).

Also, check the fluid levels monthly, that's what owners should—but often don't—do. It seems like you waited until the light went off before ever checking under the hood? If so, that's on you. Ignorance of what your fluid levels are under the hood may be bliss for a while, but eventually you pay. Again, check them monthly.

 

[bensemailis]

When I checked last month the level was fine, I don’t have it serviced at the dealer because it would be a 6 hour trip each time. I would top off the fluids myself if it didn’t have that bracket in the way. Is there a way to remove the bracket and top it off without voiding the warranty?

 

[FI Spyder]

Been working on cars my whole life, and as far as I have learned, the cooling system is sealed, and going between 1/4 and 1/2 gallon low on coolant would indicate something is amiss. The most frustrating part is I can’t fill the coolant reservoir myself without fear of voiding the warranty.

I am wanting to know what you all think, I have always found the responses on this forum helpful, although have never posted myself. Do any of you think there is a way to refill the tank without leaving evidence of removing the tamper proof bracket? And do you guys/gals think GM should honor the warranty for this kind of repair since we cannot perform a simple top off ourselves?

2012 volt 60k miles

Not sure why you can't do this. Did it myself yesterday. Take out the pop ups that secure the front cover there is a depression to get a blade under. With something curved pull the flap forward hiding access to the bolt that holds the tamper proof bracket on. I syringed out the coolant down to sensor, not the bottom of tank (don't want to activate anything, even with car off). Add new coolant (make sure you have correct one, there are two types of Dex-cool) to label. I left the bracket off so I could do this periodically (in one post the dealer did this either on purpose or forgot to put it on). This allows you to replace a portion of coolant with fresh chemicals throughout the life. Replace tank top, it will click when in final position. You could put the bracket back on if you are worried about "warranty". Put plastic cover back on, replace pop ups.

 

[obermd]

The coolant system, while sealed, is only sealed to the PSI listed on the tank cap. In the case of my 2017 Volt, the battery and HV coolant loops are only sealed to 5 PSI. This means that any positive pressure more than 5 PSI above ambient air pressure can cause them to evaporate. It also means that anytime I drive I-70 west from Denver to Summit County, CO I have an effective PSI max of 2.2 PSI and not 5 PSI. High summertime temps will also cause the pressure to increase more than 5 PSI if the system had been filled in the winter. This is why you should check coolant levels monthly.

Personally, I'm surprised the dealership didn't just refill the tank, note it in their service records, and send you on your way. Most dealerships will refill fluids for free as long as you've been using them for other service or purchased the car from them. By annotating the issue if it reoccurs then they can start the troubleshooting process to track down a very slow leak.

 

[14Volts]

I filled mine few months back on my 2014. Removed the top cowl cover up front and removed the tamper proof. It wasn’t filled all the way when I bought it new, I inspected everything prior to taking delivery. I’d post pictures here but I can’t see a link on my phone.


Sent from my iPhone using Tapatalk

 

[Steverino]

When I checked last month the level was fine

You are saying it went from fine (level with the top of the black sticker) to empty in a month?

 

[bheckel]

So, a week and a half ago I got the dreaded “service high voltage charging system” message and a MIL. I pulled the code and of course it was P1fff. I knew my coolant was too low when I inspected the tank. Sadly the closest EV certified dealer is an hour and a half away, and the tech was booked a week and a half out. Not a huge deal I drove my 1 ton truck until today. Drove the volt the hour and a half one way, told them about the coolant tank, and 3.5 hours later the diagnosis is “unknown” they tested the cooling system and inspected for leaks but found absolutely nothing. Now I am out $100 and my time, which I am glad it was only 100, but it still irks me that GM wouldn’t cover it because they could not find a leak.

Been working on cars my whole life, and as far as I have learned, the cooling system is sealed, and going between 1/4 and 1/2 gallon low on coolant would indicate something is amiss. The most frustrating part is I can’t fill the coolant reservoir myself without fear of voiding the warranty.

I am wanting to know what you all think, I have always found the responses on this forum helpful, although have never posted myself. Do any of you think there is a way to refill the tank without leaving evidence of removing the tamper proof bracket? And do you guys/gals think GM should honor the warranty for this kind of repair since we cannot perform a simple top off ourselves?

2012 volt 60k miles

I just had my 2013 throw the code at 64K, it wasn't coolant related, just a warranty covered software update. Had to contact GM to get the dealer to not charge me $125. Dealer backed down.

 

[DMC5180]

I just had my 2013 throw the code at 64K, it wasn't coolant related, just a warranty covered software update. Had to contact GM to get the dealer to not charge me $125. Dealer backed down.

Ditto hear, just a software update. Mine was covered under the Voltec warranty with 1000 miles left on the warranty period. No hassles from the dealership. Took about 45 minutes while I waited. The software update changes the cold trigger threshold, of coolant level sensor, from 300 ohms to 3k ohms.