[Talan]

I think I am going to attempt dismantling the wiring where the sensor wiring comes out of. I am hoping I have a 2012 that was modded and the wiring just needs clean up.

 

[Rhepler]

I recently had the SHVCS message & took it to the local dealer; 2014 with 63K on the clock.

When I got it back, it seems to be OK but the dash display no longer includes the Accel/ Decel bouncing ball; it is simply replaced by a Gas Fuel guage in the form of a Fuel Pump. I'm wondering if I was given a software downgrade to early 2011 that ignores the coolant level sensor. Any thoughts?

 

[russella]

That part of the display is called the Driver Efficiency Gauge. If you will refer to https://my.chevrolet.com/content/da...chevrolet/volt/2012_chevrolet_volt_owners.pdf p126 "5-14 Instruments and Controls" you can see that you need to change from "Simple configuration" to "Advanced configuration". I am wondering if perhaps it has been so long that you forgot you needed to make this change, and the dealer reprogramming blew away your settings?

If so, you might also check that your preferred settings for charge cable anti-theft, anti-lockout, etc. are all still your liking.

Cheers,
-russella

 

[16falcon]

I recently had the SHVCS message & took it to the local dealer; 2014 with 63K on the clock. View attachment 171631
When I got it back, it seems to be OK but the dash display no longer includes the Accel/ Decel bouncing ball; it is simply replaced by a Gas Fuel guage in the form of a Fuel Pump. I'm wondering if I was given a software downgrade to early 2011 that ignores the coolant level sensor. Any thoughts?

I think they just reset the display. Easy to change back to the “Enhanced” display. From the owner‘s manual:

Instrument Cluster Display Configurations
There are two instrument cluster display configurations to choose from. Press CONFIG to the left of the steering wheel to change the configuration. See Driver Information Center (DIC) on page 5‐41.
Choose either the Simple or Enhanced Configuration display.
The Enhanced Configuration displays the Driver Efficiency Gauge.

 

[russella]

I think they just reset the display. Easy to change back to the “Enhanced” display. From the owner‘s manual:

Instrument Cluster Display Configurations
There are two instrument cluster display configurations to choose from. Press CONFIG to the left of the steering wheel to change the configuration. See Driver Information Center (DIC) on page 5‐41.
Choose either the Simple or Enhanced Configuration display.
The Enhanced Configuration displays the Driver Efficiency Gauge.

jinx

 

[Rhepler]

jinx

Duh, Thank you both for your help. When I bought the car new the Enhanced Configuration was displayed & never knew of the simple display.
Thanks again.

 

[pblair]

I ordered this defeat device back in 2016, but I didn't get around to installing it and it sat in my garage ever since. I started getting a SHVCS message a month or two ago, but I was able to clear it with torque and a standard ODB-II adapter. The error would usually pop up at the end of charging and after clearing it, it would usually not come back until I drove and charged again. I installed the device earlier today and charged the car and after the charging finished, the error has not come back. The little clip was hard to reach at first before I figured out the right angle (straight up) to come with the screwdriver.

 

[Kung-Foo-Kamel]

Hi everyone, I had this BS come up on my Volt as well, resetting the codes would allow me to charge up use the battery, but on return from a drive the error would always be back, and I would have to clear the DTC's again.

This was an easy fix, visited my nearest electronics shop (Jaycar in AU) picked up a packet of 24kohm resistors for 85 cents, unplugged the coolant level sensor, cut the stupid plug clean off, soldered 1 resistor to the wires and covered in double insulated heat shrink with internal adhesive (keeps moisture out), reset the DTC's and she is good to go.

Now the codes are still in memory, but they don't do anything, I don't get any warnings, no issues and I can charge and drive just fine, I assume you will need to go for the Tech 2 system if you want to clear the codes from memory completely, but for me, I don't give rats backside, as long as the vehicle operates the way it should and I don't see any stupid warnings when I turn it on, its all sunshine and rainbows.

Personally anyone with this issue, should try this first, before visiting a dealer, with the exception of cutting the plug off, as some of you may have some sort of Warranty, but for me, here in the AU, Holden don't even exist anymore, so I have one the most expensive pieces of abandonware in Australia anyway, and I'm pretty sure Mr Chevy wont be back in my country anytime soon as I think even our prime mincer would belt the crap out of him with old cricket bat.

FYI, I used the VCM Suite (HP Tuners) to do the reset, almost 100% sure this thing can only flash the ECU and some limited items in the BCM, and I dont think it does anything more with resetting codes vs cheap scan tools.

If this fix doesn't work, then go down the path and purchase a VX Nano, which I still might do anyway as the more I can fix on this car myself, the longer it will stay out of recycling yard.

 

[16falcon]

but for me, here in the AU, Holden don't even exist anymore, so I have one the most expensive pieces of abandonware in Australia anyway, and I'm pretty sure Mr Chevy wont be back in my country anytime soon as I think even our prime mincer would belt the crap out of him with old cricket bat.

Not so fast, they are already back. You will even be able to buy a Corvette ($$$)!

GMSV: New GM Cars for Sale in Australia & New Zealand

GMSV hand-picks the most ionic vehicles in GM's portfolio and brings them to Australia and New Zealand. Enquire online for additional information.

www.gmspecialtyvehicles.com

 

[Kung-Foo-Kamel]

Not so fast, they are already back. You will even be able to buy a Corvette ($$$)!

GMSV: New GM Cars for Sale in Australia & New Zealand

GMSV hand-picks the most ionic vehicles in GM's portfolio and brings them to Australia and New Zealand. Enquire online for additional information.

www.gmspecialtyvehicles.com

Yeh just what Australia needs, more US oversized gas gusling penis extensions.

My next car will be one of the Hyundai/Kia Electrics, GM dropped the ball when they never exported the Bolt

 

[jayoldschool]

Just picked up an only NIB plug, going to install it on my ELR.

 

[Ryan IL]

Hi - newest member with this problem. I think I've read every page and still have some questions.

Dealership reprogrammed after finding P1FFF and P0AA6 2 weeks ago. I don't know if they did hpcm2 and the BECM, but will find out today. SHVCS came back, and they now want $993 to replace the sensor of course. I'm handy with cars, but I'm no technician, so I have a few choices: 1) thinking about using a defeat plug, and then either buying a vcx nano to clear the SHVCS error or having my local shop do it for me, 2) trying to replace the sensor myself without replacing the coolant tank, and reprogram.

1) Does anyone have the part number for the sensor, and is there a walkthrough to replace?

2) Is the VCX easy enough to use? If so I'd much rather do this than go to the dealer every time, but has anyone posted instructions on doing this software update?

3) Since I already have the error, are these even my best options?

I've read a few accounts from members going through these steps and still being stumped, or having the defeat in place and the code coming back. I just want to take the most logical steps if someone can advise.

Thank you!

 

[nismoRB]

Hi - newest member with this problem. I think I've read every page and still have some questions.

Dealership reprogrammed after finding P1FFF and P0AA6 2 weeks ago. I don't know if they did hpcm2 and the BECM, but will find out today. SHVCS came back, and they now want $993 to replace the sensor of course. I'm handy with cars, but I'm no technician, so I have a few choices: 1) thinking about using a defeat plug, and then either buying a vcx nano to clear the SHVCS error or having my local shop do it for me, 2) trying to replace the sensor myself without replacing the coolant tank, and reprogram.

1) Does anyone have the part number for the sensor, and is there a walkthrough to replace?

2) Is the VCX easy enough to use? If so I'd much rather do this than go to the dealer every time, but has anyone posted instructions on doing this software update?

3) Since I already have the error, are these even my best options?

I've read a few accounts from members going through these steps and still being stumped, or having the defeat in place and the code coming back. I just want to take the most logical steps if someone can advise.

Thank you!

Have you resolved this yet? I am in a similar predicament. I installed the defeat plug AFTER getting the SHVCS warning. I then cleared the error with a standard OBDII scanner which seemed to fix the problem for about 2 weeks before coming back on again. I cleared it a 2nd time and it came on again a day later. I took it to the dealership in hopes that it would be covered under the Voltec warranty, but it is not. They are asking for $950 to repair. $100 for the tank/sensor and the rest for 5 hours of labor to flush, fill and bleed the coolant system. I am tempted to have them just clear the codes and keep the vehicle in hold mode, so that I can reinstall the defeat plug before th

 

[Ryan IL]

Have you resolved this yet? I am in a similar predicament. I installed the defeat plug AFTER getting the SHVCS warning. I then cleared the error with a standard OBDII scanner which seemed to fix the problem for about 2 weeks before coming back on again. I cleared it a 2nd time and it came on again a day later. I took it to the dealership in hopes that it would be covered under the Voltec warranty, but it is not. They are asking for $950 to repair. $100 for the tank/sensor and the rest for 5 hours of labor to flush, fill and bleed the coolant system. I am tempted to have them just clear the codes and keep the vehicle in hold mode, so that I can reinstall the defeat plug before th

I replaced the sensor myself for $22 part #22922224, but the SHVCS warning came back. I purchased the VCX Nano to clear my own codes and update the software. It's a pita to install and learn, but it works very well after the learning period. If your software for the HPCM2 and BECM have not been updated, that would be your best starting place, even if you have the dealership or another mechanic with AC Delco SPS software do it.

According to a Volt tech I spoke with (not at the dealership that wanted $1000 for the sensor and tank), sensor failures are rare and would also set P1FFE or P1FFD code. He suspects mine could be the battery heater, but can't tell from afar. My local mechanic is looking it over today while he replaces the exhaust manifold gasket, so hopefully I'll know more soon.

 

[KNI]

Hi - newest member with this problem. I think I've read every page and still have some questions.

Dealership reprogrammed after finding P1FFF and P0AA6 2 weeks ago. I don't know if they did hpcm2 and the BECM, but will find out today. SHVCS came back, and they now want $993 to replace the sensor of course. I'm handy with cars, but I'm no technician, so I have a few choices: 1) thinking about using a defeat plug, and then either buying a vcx nano to clear the SHVCS error or having my local shop do it for me, 2) trying to replace the sensor myself without replacing the coolant tank, and reprogram.

1) Does anyone have the part number for the sensor, and is there a walkthrough to replace?

2) Is the VCX easy enough to use? If so I'd much rather do this than go to the dealer every time, but has anyone posted instructions on doing this software update?

3) Since I already have the error, are these even my best options?

I've read a few accounts from members going through these steps and still being stumped, or having the defeat in place and the code coming back. I just want to take the most logical steps if someone can advise.

Thank you!

Totally overpriced quote. Find another dealer.

Just had my sensor replaced and it costed like..

• GM fix kit about 90$
• Sensor about 60$

And that includes shipping to Finland + EU import tax on US parts + VAT 24%

Labor (sensor change, HPCM2 reprogram including GM mandated measurements) was 200$ or about 1-2hrs on top of that.

993$ is just pure rip-off.

 

[Ryan IL]

Totally overpriced quote. Find another dealer.

Just had my sensor replaced and it costed like..

• GM fix kit about 90$
• Sensor about 60$

And that includes shipping to Finland + EU import tax on US parts + VAT 24%

Labor (sensor change, HPCM2 reprogram including GM mandated measurements) was 200$ or about 1-2hrs on top of that.

993$ is just pure rip-off.

100% correct. What was in the fix kit, or what part number?

 

[KNI]

100% correct. What was in the fix kit, or what part number?

Based on the info on receipt it looks to be this below. (Other sites name it Connector Asm,Wiring Harness W/Leads)

Connector 19260759 | GMPartsDirect.com

19260759 - Connector

www.gmpartsdirect.com

And now the actual monetary values (instead of from top of my head):

• Guided diagnostics (prolly means reading the codes, loading the PDF from GM and then reading the service manual) - 80€
• Labour - 149€
• GM fix kit - 19260759 - 57,20€
• Sensor - 22922224 - 34,09€

Total of 320€ ~ 350$.

 

[Ryan IL]

Based on the info on receipt it looks to be this below. (Other sites name it Connector Asm,Wiring Harness W/Leads)

Connector 19260759 | GMPartsDirect.com

19260759 - Connector

www.gmpartsdirect.com

And now the actual monetary values (instead of from top of my head):

• Guided diagnostics (prolly means reading the codes, loading the PDF from GM and then reading the service manual) - 80€
• Labour - 149€
• GM fix kit - 19260759 - 57,20€
• Sensor - 22922224 - 34,09€

Total of 320€ ~ 350$.

That's great info - thanks!

 

[Ryan IL]

So, correct me if I'm wrong: If wiring is intact (constant 5v) and sensor is good (24.7k ohms), there is no need for the defeat plug, right? I replaced my sensor, and found that the old one reads 24.7k. Replaced the wiring harness, and still get 5v. Is there any benefit to getting a defeat plug that mimics the 24.7k ohms of resistance I'm already reading?

Also wondering if there a limit to the number of times I can reprogram my HPCM2 with my SPS subscription.