2018 Chevrolet Volt electrical system problems

“My 2018 Chevy Volt is experiencing the EXACT same symptoms as GM's Battery Energy Control Module (BECM) Warranty Extension Program N232432680 AND Program N202307990 AND TSB 19-NA-206. My vehicle falls within the guidlines of affected vehicles, yet GM will not honor their program specifications. My vehicle has stalled while driving on the highway, not started, reduced power, and will not charge or depletes a full charge within 30 minutes. I stalled while driving 75 mph on a freeway. My car also would not allow me to shift into park while returning home, then tells me to shift into park when I am trying to tleave for work. GM tells me that "Your VIN does not fall within the repair requirements, even though your vehicle exeriences everything taking place and meets the standard requirements." The dealership tells me that I have to take it up with GM. I have children I drive to school, I drive to work, and I do not think that something of this nature, with the EXACT SAME symptoms that GM claims is happening, with the EXACT SAME codes related to the issue, with very possible safety issues being experienced should be overlooked. This has been happening for months, and…”

“My 2018 Chevrolet Volt LT (VIN [XXX]) suffered a Battery Energy Control Module (BECM) failure at 142,185 miles. Gandrud Chevrolet in [XXX], diagnosed the failure, citing GM Technical Service Bulletin 18-NA-261 and diagnostic codes U2619, U2620, U2621, U2622, U2623 and U2624. The dealer replaced the BECM (part 24296900), programmed it, and performed associated work. The repair was completed XXX. The invoice was $3,160.70; I am seeking $3,066.25 in reimbursement for the qualifying repair expenses. GM denied coverage because my VIN is excluded from Special Coverage XXX, despite the dealership-confirmed BECM failure. I pursued the matter through GM Customer Assistance (case 106790207), mediation (case XXX), and Wisconsin DATCP (case XXX). GM maintained that the special coverage does not apply to my VIN. NHTSA previously investigated BECM failures under PE23022. However, owners continue to report similar problems in 2026, including reduced propulsion, inability to drive or restart, charging failures, and reported BECM failures. I ask NHTSA to review these 2026 complaint records alongside mine: XXX A sudden loss of propulsion can leave a vehicle unable to maintain…”

“While driving through a canyon to get home, my check engine light came on and I saw the message "Propulsion Power Reduced" on my dash. The speed limit on that road is 65 mph, and I lost power going up a hill and went from 65 mph on cruise control to 48 mph. There are a lot of cars on that road, and it could've caused a serious accident. My vehicle does exactly what the GM extended coverage describes and is within the parameters, but somehow my vehicle does not qualify. This could've been bad on that road is it was raining or snowing.”

“FAILURE SUMMARY & SAFETY RISK: While operating in live traffic, the vehicle experienced a sudden loss of motive power and entered a "Propulsion Power Reduced" failsafe mode, creating a severe rear-end collision hazard. The vehicle is currently grounded and remains available for inspection upon request. WARNING SYMPTOMS & DIAGNOSTIC CODES: The instrument cluster illuminated the Malfunction Indicator Lamp (Check Engine), the ABS warning indicator, and displayed a persistent "Propulsion Power Is Reduced" message. A diagnostic trouble scan confirmed active high-voltage communication failures and powertrain faults: U2603 (Lost Communication with Hybrid/EV Battery Interface Control Module), P25A2 (Brake System Control Module Requested MIL), and ABS code C0500-00. PRIOR HISTORY & FAILURE TO CURE: This identical high-voltage Battery Energy Control Module (BECM) failure previously occurred in December 2025 at 97,808 miles and was presented to an authorized Chevrolet dealership for repair. The facility claimed the vehicle was repaired, but the exact same catastrophic high-voltage failure recurred in under 4,000 miles (at 101,635 miles). MANUFACTURER POLICY & OBSTRUCTION…”

“The vehicle frequently fails to register that the transmission has been shifted into Park. When this happens the instrument cluster displays "Action Required / Shift to Park" and the power (STOP/START) button will not shut the vehicle off. The condition is intermittent. I can usually clear it only by shifting through the gear positions and back into Park repeatedly, sometimes many times, before the vehicle will power down. SAFETY RISK: Because the transmission control module does not confirm Park, I have no assurance the parking pawl is engaged when I leave the vehicle, creating a rollaway hazard. The vehicle also cannot be shut down, which leaves its systems energized and drains the 12-volt battery, risking being stranded. I now apply the parking brake at every stop as a precaution. WARNING MESSAGE: The "Action Required / Shift to Park" message first appeared within days of purchase. I bought the vehicle used on 07/29/2026 at 69,471 miles and reported the fault to the selling dealer on 08/10/2026, twelve days later. CONFIRMED BY DEALER: Yes. On 08/19/2026 the selling dealer's service center diagnosed the cause as "internal shifter microswitch failure" and…”

“While driving on a highway the car started to hesitate, a message appeared on the console "Propulsion power is reduced" and the engine light turn on. After driving some miles, a new message appeared: "Engine unavailable, service soon" and the car only ran on electric power, no motor engine. I had the same problem 3 year ago and the dealer identified the problem as a shorted EGR valve. This time I knew this shorted EGR valve burns the F3 fuse. I managed to get to a car part shop and bough several fuses (15 amp). After replacing the fuse 3 times I managed to get to the dealer. The repairs cost $3000+ (up from $1000+ 3 years ago). This problem is well documented on the GM service technical bulletin "21-NA-116" dated February, 2023. Three years ago I was in the middle of nowhere in South Texas and it took 6 hours to get a tow truck This time I was lucky enough to be close to to a town that the remain battery power was enough to get to the store where I bought the fuses. GM should recall this part and do a proper fix”