OK folks, WOT's Replacement Coolant Level Sensor (SHVCS Defeat Plug) is ready for deployment!
I helped someone I know very well to create a low cost replacement level sensor that plugs into the connector harness the factory coolant level sensor.
Once completed, (following the special instructions) it "mimics" a properly operating sensor at the correct coolant level, PERMANENTLY mitigating the possibility of ever getting the dreaded SERVICE HIGH VOLTAGE CHARGING SYSTEM (SHVCS) message.
Unfortunately, it's likely not a matter of IF but WHEN as these level sensors have been failing left and right (IMO due to a combination of temperature and vibration) and currently there's no plans to redesign the sensor. (apparently content on letting the dealers replace the sensors in some cases almost bi-annually! lol) LOTS of documented cases in our main SHVCS thread here: http://gm-volt.com/forum/showthread....m-quot-Message
The only real caveat in using the WOT's Coolant Level Sensor (SHVCS Defeat Plug) is that the owner must visually check their battery coolant level at least monthly (as outlined in the owner's manual) just as car owners have been doing for over 100 years! lol
Additionally, there's no real concern that using this device could result in a battery overheat issue as those are completely different DTCs (based on the battery temp sensors) and all have fail-safe behavior that utilizes "reduced propulsion power" to protect the battery even if there's zero coolant.
(keep in mind on many EVs, such as the Nissan Leaf, coolant isn't even used to cool the battery)
This device will not affect your warranty as it is an "aftermarket replacement part" as stipulated under the Magnuson Moss Act.
So far, a few dozen of these have been constructed (version 1) and will ship with complete instructions (that I had a hand in) that must be followed to the letter in order to prevent triggering the P1FFx series of DTCs while installing the device.(basically the car must be "asleep" when the device is installed as the system monitors the coolant level even when OFF or when charging)
IMPORTANT NOTE: This device needs to be installed BEFORE the "Service High Voltage Charging System" appears as once triggered there is NO CHOICE but to visit a dealer and let them try to figure out what’s wrong (bad level sensor usually) THEN eventually figuring out the only way to CLEAR the combination of DTCs P1FFF and P0AA6 is to “Reprogram the HPCM2” (they will say “a software update was needed” but…) Unfortunately the coolant level sensor is not listed as a Voltec or emissions warranty part, so typically unless you are under the original "bumper to bumper" warranty they will try to ding you anywhere from $100-500 for these repairs!
So to be effective at preventing this annoying and costly repair (some people have had the sensor replaced 3 times!) WOTs Coolant Level Sensor (SHVCS Defeat Plug) must be installed pre-emptively on a properly operating car.
Currently it will work on ALL Gen1 Volts, Amperas, and ELRs.
*NOTE*The Gen2 Volt is a bit different as the sensor is now part of the reservoir (potentially making the repair even MORE expensive) However we have yet to experience anyone with a Gen2 getting the SHVCS message yet, so perhaps the Gen2 will never have the issues the Gen1 cars are plagued with.
We have been testing this solution now over the past couple years and have 12 cars (including one Volt of each model year plus a MY14 ELR) operating with various prototypes of this device for the past 12-months with no ill effects. MISSION ACCOMPLISHED!
So to purchase WOT’s Coolant Level Sensor (SHVCS Defeat Plug) you can submit $29USD (includes NA shipping*) to PayPal using the email address(copy and paste address above) and it will be mailed out to you including complete instructions. *UK and Europe add $5(including complete instructions) MAKE SURE YOU ADD YOUR NAME AND MAILING ADDRESS TO THE "MESSAGE TO SELLER" FIELD IN PAYPALCode:email@example.com
So available at this price for a limited time only as eventually they will be adding WOT's Coolant Level Sensor onto eBay (likely at a slightly higher price) at some point, but for our gm-volt.com forum members it will be available by simply submitting payment and it will be mailed out within 7 business days.
The shipment should take place within 7 business days of ordering and they are being shipped to the U.S. via "small packet" airmail service. The delivery standard for this service is 4-10 business days (I presume depending on location)
So please expect 2-3 weeks for delivery. If it's been longer than 3-weeks then PM me your name and address and I will confirm.
*Canadian orders are going via simple oversized letter postage but should be there in about the same period
ALSO please remember to add your mailing address to the PayPal "message to seller" as sometimes PayPal does not forward it.
If we had to contact you for your mailing address it will add additional shipping time obviously
PS> Feel free to post any questions/comments in this thread