Chevy Volt 2011-2015 SHVCS Defeat Plug
Chevy Volt 2011-2015 SHVCS Defeat Plug
Chevy Volt 2011-2015 SHVCS Defeat Plug
Chevy Volt 2011-2015 SHVCS Defeat Plug

Chevy Volt 2011-2015 SHVCS Defeat Plug

Regular price $40.00 Sale

 In Stock.  Product usually ships within 1-2 business days.

Note: Please include your telephone number for customs clearance on international orders, otherwise your order cannot be processed.

Supported for Chevy Volt 2011-2015 models (Service High Voltage Charging System) issues from poorly designed GM battery coolant sensor or retrofit models (2011-2012). 


2011-2015 Chevy Volt 

2013-2015 Cadillac ELR

2011-2015 Ampera - (EUROPE)

Overseas customers should validate the coolant level sensor plug is the same as the female pigtail provided by the pictures shown below before ordering if for an Ampera.

This product helps to prevent trips to the dealership when the battery coolant sensor in the Chevy Volt malfunctions and causes a permanent check engine light code to be tripped, which then causes you problems with charging your volt.  This can happen even when your coolant level is functional.

GM did a poor job on the design of this particular sensor, and even hitting a large bump can trigger a charging system check engine code.  Once you have 'latched' codes present, it requires a reflash of the PCM software.  Dealerships charge anywhere from $150-$300 to perform this task if your vehicle is no longer under warranty.  This particular product basically creates a constant feedback loop to the ECU with the proper voltage stabilized so that even sensor failure will not trip the code requiring a trip to the dealership.

The only downside is that you must now check the coolant level monthly in your vehicle, which your owners manual recommends anyways.  If you do end up running low on coolant the coolant temperature is also monitored, and will throw a code if you do end up running low as documented on the gm-volt forums.  Hundreds of Volt owners have done this with good results to date.

An instruction manual is included with the plug set.  Velcro is also included to secure the plug/harness inside the engine compartment to existing wires.

This plug is also known as the 'WOT coolant SHVCS defeat plug' on the gm-volt forums.  We decided to start offering this product once many Volt owners waited months for product which never did arrive.

Also, we also include a female version of the plug which can cap the existing sensor in the reservoir to prevent any corrosion on the original sensor.  This additional plug may replace the factory retrofitted models also where the GM dealerships did a poor job retrofitting the 2011-2012 models after the recall.


Product is crimped with the proper delphi crimp tool and is also soldered to guarantee a solid robust connection for maximum reliability.  Factory OEM delphi wire seals are also used to guarantee moisture/rust protection.   The bypass resistor used is military grade and will withstand temperatures up to 150c (300F) temperatures, not cheap consumer grade components.  Engine bay temperatures may reach up to 250F in some scenarios.


Price: $40.00 USD.

Shipping to USA - $5.00 USD

Shipping to Canada + $26.00 USD (includes pre-paid import/customs fees)

Shipping to Europe + $22.00 USD (purchaser pays import/customs fees upon arrival)

Other Countries not designated above are automatically calculated by our payment provider.

Note: US to Canada orders generally take less than 7-10 days to arrive.  We normally process orders same-day or next business day.  First Class International Shipping to Europe takes between 7 and 20 days.  Any Import Fees/Customs are the responsibility of the purchaser in countries outside of USA and Canada on orders placed after 2/6/2023. Product ships from USA. 

Note: USPS does not refund late shipments for 2-3 day Priority Mail or Ground Advantage, only Priority Express Overnight Shipping.

Installation Manual

Download Installation Manual - 7/14/2019

Note: Our e-mail address has changed.  Please e-mail eastmanrd1(at) to contact us. We have had problems with our other e-mail provider blocking e-mails.

VXDiag hardware and software

If you need to re-flash the software for a latched code instead of visiting a gm dealership or professional shop, you can follow the procedure here from vxdiagshop and obtain VXNano GDS2 USB Version VXDiag VCX NANO for GM/OPEL 2022.5 GDS2 Tech2WIN Diagnostic Tool (

Instructions for using VCXNano GDS2 - Set up VXDIAG VCX NANO GM with Techline Connect (VMware Solution) -

Bulletin 21-NA-224 states to reprogram the hpcm2 and becm after inspecting and confirming no battery cooling system leaks.  If you have a P1FFF or P0AA6 codes you will need to perform this reprogramming after installing the defeat plug.

Customer Testimonial


The plug works like magic in our 2011 Volt.   I have mechanical skills and was going to make one. Buying your solution was a lot easier.  Plus, I won't have to worry about your product failing as they use the right temp rated materials and are both crimped and soldered.  -- Matt