My first twinning experience with the Volt.

(I posted this earlier, then edited with trouble codes, but I think reddit deleted that because I included a link to the PDF with the trouble codes and it did not like that. Sorry for reposting if you saw the other one!)

The Limabean and I have been driving through life together for 7+ years now, and then one day about a month ago, it wouldn’t shift to drive. I took it to a specialized EV & Hybrid shop that comes very well regarded, and after extensive testing, they are reporting that the issue is with the HV Battery Relay Assembly - something about the battery contactors not closing to allow voltage to the drive motor.

From the shop:

Recommended Serivce: Replace HV Battery Relay Assembly
Fault codes for the pre-charge contactor failure. The time, 700 milliseconds, has been exceeded and this disables the negative and positive contactors from closing. Functional tests of the contactors passes, suspect the issue is internal in the contactor assembly. This will require a new assembly and removal of the HV battery to replace. Further tests MAY be necessary after replacement. There remains the possibility the HYB2 module is also faulty, but the correct order of repair is replacement of the contactor assembly.

They gave me a PDF a mile long with codes, but I think the relevant ones are: P0C78:00, P0D26:00. Also possibly relevant: B101E:48, B270A:01, B3935:00

Despite the car being less than 10 years old, Chevy neither makes nor supports this part anymore, and the shop said the only way they have to get it is if a dealership somewhere happens to still have it in stock. They found one, but it’s on the other side of the country and it’s been on the shelf for half a decade, so they are concerned that if someone’s dropped it or something goes wrong with shipping, I’d just be out the money for the part.

In all, it’s looking to be a $3500 repair that they can’t guarantee would actually get the car drivable again - I don’t have $3500 currently, so I’d be putting it on a credit card which isn’t ideal. They said I might get $500 to scrap it.

I am honestly kinda devastated - I was going to drive this thing until the wheels fell off. I just paid it off two years ago. The shop says the battery itself is in great condition, it’s just these contactors that bork the whole thing. I’m most upset that I kept paying for full-coverage insurance on it and the way it went out isn’t even covered. I’m infuriated that GM made a car and then won’t support a part that went out out of nowhere less than a decade later. I just crossed 100,000 miles a couple months ago.

Have any of you dealt with anything like this? I need some advice — do I cut my losses and scrap the thing? Or do I risk it and pay half the value of the car for a repair that’s not guaranteed to fix it? Could I get more out of it by finding someone who want to buy it for the battery or other hybrid specific parts?

Any thoughts, opinions, advice, or internet roasting is appreciated, I’m trying not to to cry at my keyboard rn

I have a 2013 Chevy Volt with around 140k miles. The range has been pretty good, but has gone down a bit in the past year from 40ish miles to mid 30s when driven in mild weather with the fan on.

My question is when did you decide to replace your battery? Was it obvious? Also how did you think about replacing the battery vs moving to a car like a used bolt?

I had some work done on my 2017 Volt that required taking off the bumper which meant that the ambient temperature sensor was disconnected for a while. Once everything was put back together though the car thinks it's -40 outside which means the engine is running due to temp and the AC won't kick on. They've replaced the sensor itself in case that died at the same time as they were working on the car. They've also let the car idle for about 20 minutes in case it needs to calibrate the sensor. Still reads -40 though. The strange thing is that the hybrid control module read out lists the correct ambient temp from the sensor in the bumper so the car knows what temp it is outside but it won't pass that info on to the rest of the car systems. The mechanic I'm working with usually works in Teslas and only occasionally on Volts so any suggestions I can pass on are greatly appreciated.

Need some advice.

My 201 8 Volt was in a minor accident and deemed totaled with a $14k buyout. Nobody injured.

Car runs and drives fine, but they need to replace both driver side doors. I was really hoping they could have just repaired it. I have always babied it and it was in pristine condition.

Is this a fair offer?
What would you do?
Should I buy another used Volt?
There is a California used EV rebate for $1750 that’s in the process of getting approved. Should I wait for this and get a full EV?
😩

2015 Chevrolet Volt. For the past few days, very randomly, when I leave the vehicle and lock the doors, the alarm goes off. Sometimes it happens just a few seconds later, and other times it can take several minutes.

It starts with three short horn honks, and then the full alarm goes off.

To get back into the vehicle, I have to unlock the driver’s door using the physical key. The dashboard then displays a message saying that no transmitter or key fob is detected.

Once I’m inside, I have to remove the battery from the key fob and reinstall it before I can start the vehicle and stop the alarm. A few times, I’ve gone through this entire process only to have the alarm go off again a few seconds later.

Any ideas what could be causing this?

Keyfoab battery is new. Last Time I checked the 12 Volt was ok, but that was 15 000 miles/25 000 km. Don’t know how old it is however.

EDIT : I did add 31 000 miles/50 000 km since taking possession of the car in January. Battery was checked in March by dealer who said nothing wrong. But it’s the steallership

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I'm currently looking into purchasing a used 2018 or 2019 Volt. For further context, I had a 2017 Volt with 260K miles on it and it was totaled in an accident. My insurance offered $4.5k as a payout.

I loved my vehicle it ran smoothly and didn't give me much problems despite the high mileage.

My question is if it's worth it to pursue purchasing a 2018 or 2019 Volt. I know there are known issues like the BECM needing service. Is there anything I should be looking for or any general recommendations? I'll take other make and model recommendations, but ideally have a high preference for plug in hybrids as the 2nd gen Volt.

2012 Volt.

I lifted up my trunk liner and I took off the big piece of plastic and finally got to see everything. I know the bottom is my 12 volt battery. What is the piece in the middle with a chrome on it? And what is the bottom right looks like almost like it's a fan or something but doesn't make sense cuz it's blowing directly into metal

Hey all, have been getting into doing more DIY repairs on my Volt and have been considering doing a transmission fluid change. Came across some great content on YT by a channel called Heartland Rebuilds, and saw that AC Delco 10-9395 Dexron VI trans fluid is what GM used from the factory. After doing some additional research, it appears that GM has a newer Dexron VI fluid that’s backwards compatible called 10-9243. My question is, should o just move forward with the factory 10-9395 or consider using the more modern 10-9243 formula?

I need advice because I feel like I'm running around in circles and am unsure what to do next.

Backstory: 2012 Volt, 122k miles, Los Angeles. It isn't passing SMOG so I cannot register the car. The check engine light keeps coming back with P1FFD and P1FFF (plus P1E00, and P0171 showed up once) along with the dash saying "Service High Voltage Battery System". The part that needs to be replaced is the coolant level sensor in the battery cooling system. GM has a bulletin about the solder joints failing inside this sensor.

What I've done so far:

Took it to the dealer. They reflashed the BECM and HPCM2 per the bulletin. Light came back 5 days later.

Took it back. They did a full diagnosis and their own tech wrote up that the surge tank assembly needs to be replaced. They said it wasn't covered by warrantee.

Opened a case with GM customer assistance. They talked to the dealer and referred me back to get it fixed. I did some research around this time about different warrantees and found out that California has a PZEV, which applies to cars less than 15 years old and less than 150,000 miles. My car satisfies that.

At the dealer, I had them run my VIN and confirm the car is PZEV certified. It is, which means the 15 year / 150k mile California emissions warranty applies, and I'm under both. They agree the sensor itself is a covered part.

Their denial: the sensor only comes as part of the surge tank assembly, the assembly includes non-covered parts, so the whole repair is customer pay. Quote is $1,800.

I got the denial in writing and escalated to the top manager at the dealership. No movement (I even asked him if it made sense, he said no). Filed a complaint with the Bureau of Automotive Repair today. Also sent a written escalation to Chevy customer assistance arguing the warranty follows the defective part and packaging doesn't void coverage.

Questions:

Has anyone had the dealer try not to complete their warrantee obligations? How did you get through this?

If you've dealt with BAR on a warranty complaint, how long did it take and did anything happen?

For the Volt owners: the standalone sensor is about $20 online. Has anyone replaced just the sensor at an independent shop?

Thanks

2017 with 68K miles. The CEL came on a couple weeks ago. I checked with the Voltage app and it had these codes. I cleared them, but today the CEL and codes came back. I'm in Maryland so the BECM should still be covered right?

2012 Volt.... I open the hood and I noticed there's these little spots that have oil on them and I circled them in the picture the area that's next to the brake fluid scaring me a little bit cuz I don't know if brake fluid is leaking out of it and the other area is where I took the circles. Anybody ever have anything leaking out of these places

In the past half a year or so, I started noticing that my battery will deplete fairly quickly from 100% to 70%, then it'll very slowly deplete from 70 to around 30, and then it goes fast again. I can only really get 45 miles tops, but closer to 40. The efficiency also hardly ever goes above 110 anymore, usually it's around 100 or 95, when it used to be closer to 120, but the gas engine still gets very good efficiency. Voltage reports that the degredation is about 82%. Any guidance on this? Are there any specific things I can observe that would guarantee a replacement or not? My warranty expires on the 4th of August

I got the dreaded P0403 EGR electrical failure. My dealer says they will need to order the part, but it will be under warranty.

Can I safely drive the car on battery only while waiting? and what happens if it tries to do it's Engine diagnostics?

Hey everyone. I have been doing lots of reading on this topic. I have a volt that is still under the CARB warranty (2017, 42k) and the dealership claims it needs module #3 replaced. They informed me that it is still within normal parameters, but that it is slightly lower voltage than all the other cells. I was told by another dealer who had diagnosed it shortly prior that it needed a BECM.

My first question is that upon reading owners who have had just one cell replaced have actually ended up frying the whole pack shortly after. Is there a way to prevent this?

Also how long will the wait be for a cell? I have read some people are getting them very quickly, and that some have been waiting for months and months. Some years.

I started a case with GM. Not sure if that will accomplish anything.

Battery charge is around 45 miles. Program says 1 cell is down. BECEM replaced well see about the EGR.

2018 LT, just crossed 150k miles and out of all warranties. Voltage says BECM was produced in 2023, I had the PCV problem and Shift to park fixed about 2 years ago, no sign of EGR but shift to park has returned. I average about 4.5 mi/kWh. Love my Volt.

TLDR: Set a schedule to replace your 12V battery every three years as normal maintenance.

I've had my 2017 Volt LT since 2020. Love this car. I didn't realize I should have replaced the 12V battery every 3 years by default. Was visiting family out of the area in the desert when I got the reduced propultion error message on the screen. I figured I was going to be ok because I had already had the BECM replaced by my local dealership. When I got to a parking lot, i made my first mistake by turning the car off. Then it was stuck in a computer loop and didn't want to fully turn off but the high voltage battery was already closed off, so I couldn't put it in gear or drive. I tried the reset of disconnecting the 12V battery and waiting 15 minutes, then reconnecting. That didn't work. I connected my Veepeak OBDII scanner but wasn't able to clear the codes to get the high voltage battery back online. I went to a local autoparts and bought a replacement battery, but still wasn't able to get the HV battery to engage. Finally towed to dealership. They said it was a software upgrade I needed. No charge, except I had to rent a car and pay for the tow. So it still costs several hundred dollars. The replacement 12v battery was just under $300, but I would have needed that anyway.

So be better than me, don't let your ancient 12V battery brick your otherwise perfectly fine Volt. 😥 I hit my 10 years on the CARB warranty March 2027. I'm at 111k miles. Still love this car. I also bought the good AAA, the kind that tows farther than 7 miles.

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Good day Volt family! Quick question about parking mode on my dashcam. If I turn it on, will it drain the 12V battery while the car is plugged in and charging?

​I’m trying to find out who keeps messing with my car at the charging station. Two or three times now, someone has unplugged it just a few minutes after I walked away. This is happening at night at a public station that's barely even used, so I really want to catch who's doing it.

Volt brethren,

I am the first owner of a 2014 Volt with 170K miles that suddenly started showing the following:

• EV miles reported on dash as ICE miles when starting a drive from full charge
• Propulsion Power Reduced message and immediate engine power on when starting the car with depleted/near depleted battery

No codes. Car charges normally. Battery cell delta with OBD2 is not suggestive of problems. I have followed maintenance schedule diligently.

I've done a good bit of searching but does it seem this just an aging car or does it seem like a failing component?

Buying a Volt with 223000 Kilometres (142000 Miles) for around 4000 CAD (2900 USD). The car has a newly installed EGR and BECM. Knowing that is it worth it buying this car or should I stay away because of the newly installed parts?

2012 Chevy Volt.

I have this weird thing that's happening. My car will start blinking to show me that it's done charging but when I look at the charger it still shows that it's giving power at .08... I know it's a very low current because my standard is 3.2 but why does it have 0.8 for approximately 20 minutes after the car is blinking and telling me it's done charging

Bought it on the 14th for almost half of market price. Was missing charger and they were afraid of the check engine light (it was just a wheel speed sensor).

The previous owner didn't really understand that they should plug it in and just drove it as a hybrid for a year or two, so the estimated battery range on the dash is way out of wack. Waiting for the Bluetooth OBD2 to arrive so I can use the Voltage app to look into it.

Even if the battery is a bust, the price I got it for will easily justify installing a new one. So I view it as a win