Service Electronic Brake System Warning. This warning started coming on sporadically. When the warning appears in my dash, I will lose abs function, traction control, and cruise control. This appears to be a common problem with this year Ram truck. The fix is an abs module, and or, a hcu module.
2018 RAM 3500 electrical problems
moderate 122 complaints filed with NHTSA · avg repair $850 · see electrical across all vehicles →
Failure mileage
Complaints
122
Recalls
0
Avg fix
$850
1crash
What stands out
Of the 12 model years of RAM 3500 we track for electrical problems, this one carries the most owner complaints on file — 122.
Owners have filed 122 electrical complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
The failure pattern owners describe
Buyer takeaway: This 2018 Ram 3500 has a critical and widespread ABS/braking system failure (code C0020-01) affecting hundreds of owners, with recall 24V-896 issued but parts unavailable for months to years—dealers routinely advise driving with no ABS or traction control, and some owners report recurrent failures even after repair. Additionally, the integrated Uconnect screen commonly delaminates and causes phantom button presses including unwanted emergency calls while driving, creating distraction hazards.
Owners describe a widespread electrical failure in the ABS and braking system that manifests as intermittent warning lights and chimes for "Service Antilock Brake System," "Service Electronic Braking System," and traction control warnings—often appearing unpredictably while driving, sometimes multiple times per hour. When these warnings activate, the cruise control disengages without warning, and owners report loss of ABS and traction control functionality. Diagnostic code C0020-01 (ABS pump motor control—general electrical failure) appears consistently across complaints, pointing to the hydraulic control unit (HCU) as the primary failure point, though some dealers recommend replacing the ABS module as well.
The problem starts as early as 5,500 miles on some trucks and recurs even after repair—owners report replacing the HCU once, only to see the warning lights return thousands of miles later. This is particularly dangerous when towing trailers; owners report loss of trailer brake function during the warning events. Dealers have consistently told owners parts are on severe backorder with no availability dates, some quoting wait times of six months to over two years. Owners paying out of pocket face repair costs between $800–$2,000. A recall (24V-896) was eventually issued for the HCU defect, but part shortages have prevented repairs even for those under recall. Owners are frustrated by dealer advice to continue driving despite non-functioning safety systems, and frustrated further by reports that dealerships are prioritizing parts for trade-in vehicles over fixing customer vehicles.
Same RAM 3500 electrical reports on nearby years: 2015 · 2017 · 2019 · 2021
Failure modes owners describe
Hydraulic Control Unit (HCU) Electrical Failure
The HCU develops an internal electrical failure that disables ABS, traction control, and electronic stability control. Owners report intermittent warning lights and chimes for 'Service Antilock Brake System' and 'Service Electronic Braking System,' often appearing multiple times per hour while driving. Cruise control disengages automatically when the warnings activate. The failure is diagnosed via code C0020-01 (ABS pump motor control—general electrical failure).
When: Starts as early as 5,500 miles; recurs even after replacement—some owners report a second failure at 37,000–48,000 miles after initial repair at 16,000–30,000 miles
Symptoms owners cite: Intermittent 'Service Antilock Brake System' warning light; Intermittent 'Service Electronic Braking System' warning light; Traction control warning light illuminates intermittently; Audible chime or dinging alarm when warnings activate; Cruise control disengages when warnings appear; Loss of ABS functionality; Loss of traction control; Loss of trailer brake function when towing; Warnings may cycle on and off multiple times per trip or per hour; Warnings may temporarily clear with key cycle but often return
Codes mentioned: C0020-01
Repairs/costs cited: Dealers recommend replacement of the HCU (part number 68143491AA, superseded by 68143491AB or 68228991AD depending on application). Some owners also had ABS modules replaced (part number 68347098AB). Out-of-pocket repair costs reported at $800–$2,000 including labor ($600–$900 labor, $300–$500 parts). Parts have been on severe backorder with wait times cited from 6 months to over 2.5 years.
Recalls/TSBs owners mention: NHTSA Recall 24V-896 issued for HCU defect affecting ABS/ESC/traction control. FCA service bulletin S2005000004 (NHTSA #10181550) states to replace HCU first, then ABS ECU if code persists. Some owners report Stellantis advising them the vehicle is safe to drive even with non-functional ABS. Dealers report parts are quarantined pending engineering review with no firm ETA. Some owners report dealerships prioritizing parts for trade-in vehicles over customer repairs.
Trailer Brake Controller Voltage Failure
The integrated trailer brake controller receives insufficient voltage, preventing it from activating trailer brakes during normal braking events. One owner measured 8.3 volts instead of the required 12.6 volts needed to activate the controller.
When: At 5,500 miles
Symptoms owners cite: Trailer brakes do not engage when towing despite applying truck brakes; Difficult to slow down vehicle while towing; Trailer may slide or jackknife during braking
Repairs/costs cited: One owner installed an aftermarket trailer brake controller to restore function. No dealer repair information provided.
Uconnect 8.4 Screen Delamination
The integrated touchscreen display begins to delaminate, separating from the LCD backing. The delamination causes a leaking substance to drip downward onto control buttons and other electrical components, including exhaust brake and trailer brake controls. The delaminated screen triggers phantom button presses, causing the vehicle to make unwanted calls, adjust audio volume, activate cameras, and change settings while the truck is in motion.
When: Typically appears outside the warranty period; one owner reported it at 53,000 miles, another at 6,000 miles
Symptoms owners cite: Screen visibly delaminating or separating; Leaking substance dripping from screen onto controls below; Screen making phantom button presses while driving; Vehicle randomly calling stored phone numbers; Vehicle activating SOS emergency button unintentionally; Rear view camera turning on automatically while driving; Radio volume jumping to 100% randomly; HVAC controls and other integrated functions changing without driver input; Front and rear parking sensor functionality affected by dripping substance
Repairs/costs cited: Dealer repair requires complete replacement of the screen and controller assembly at a cost of approximately $2,000 or more. Screen is integrated with ABS, traction control, trailer brake controls, parking sensors, HVAC, ride height controls, and emergency calling functions.
Recalls/TSBs owners mention: Dealers acknowledge the delamination is a known issue on several model vehicles. No recall or forced reimbursement mentioned in complaints.
Stereo/Radio Malfunction with Unintended Actions
The stereo system malfunctions by jumping between stations and randomly initiating Bluetooth calls to contacts stored in the vehicle's phone system without driver input. The unintended audio and calling creates a distraction that forces the driver to pull over to address.
When: Reported on one vehicle; specific mileage not stated
Symptoms owners cite: Radio tuning jumps between stations without driver input; Vehicle randomly calling contacts from phone contact list; Radio turns on unexpectedly; Audio volume changes without driver input; Bluetooth connectivity issues
Repairs/costs cited: Dealer replacement of stereo/radio unit. One owner had multiple stereo replacements.
Engine Limp Mode Due to Failed Turbo Actuator
At low mileage, the turbo boost actuator fails, causing the engine to enter a severe limp-mode condition that drastically reduces power and acceleration. The vehicle becomes unable to maintain highway speeds, creating a traffic hazard.
When: At approximately 46,000 miles
Symptoms owners cite: Check engine light illumination; Significant loss of engine power; Severe reduction in acceleration; Vehicle unable to maintain safe highway speeds; Engine in limp mode/derate condition
Repairs/costs cited: One owner reported a failed turbo actuator diagnosis; no repair details or costs provided.
Evaporator Coil Premature Failure
The air conditioning evaporator coil fails prematurely, causing a chalky white powder to be blown through the ventilation system into the vehicle cabin when the AC is activated.
When: At 6,000 miles
Symptoms owners cite: White powder/chalk-like dust blowing from AC vents; Visible debris inside vehicle when AC is used
Repairs/costs cited: Repair requires removal of the dashboard and center console to access and replace the evaporator coil. One owner noted the same failure has been reported on 2014 and 2015 model year vehicles. Vehicle was not repaired.
Engine Thermal System Warning (Check Engine/Coolant Temperature)
Check engine and coolant temperature warning lights illuminate, often related to thermostat and coolant sensor issues. One complaint referenced NHTSA Campaign 21V798000 (Electrical System).
When: At approximately 67,000 miles
Symptoms owners cite: Check engine light illumination; Coolant temperature warning light illumination
Repairs/costs cited: One owner was diagnosed with thermostat, coolant sensor, and air intake heater relay needing replacement. Vehicle was not repaired.
Recalls/TSBs owners mention: NHTSA Campaign 21V798000 referenced, though complaint notes VIN and vehicle year were not included in the campaign information.
Synthesized from 122 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 5 most recent
The Anti-Lock Brake & Electronic Braking System error caused the internal Trailer Brake system to shut off trailer brakes just like it shuts off the cruise control when warnings come up on the dashboard. The incident happened Aug 28, 2023 while following my son and my wife in a vehicle ahead of me. I had to change lanes to try to avoid something that suddenly came across in front of my vehicle. I…
Recall C4B with known issue and known remedy but “no parts available.” Contacted RAM and with no parts they have no solution. You can rent an auto out of pocket and possibly be reimbursed. No option for buyback or solution. Recall came out 12/5/2024.
Traction control and abs lights have been coming on randomly while driving over the past several years. Seems worse and more frequent in cold temperatures. Scanner reads code C0020. Cruise control suddenly shuts off when this happens causing a safety hazard especially to those traveling behind. Dash lights and constant chimes are very distracting while driving. No abs makes winter driving more…
Right before 36000 miles the ABs and Traction control lights come on and off intermittently. I took the truck to my local dealer and was told 2 components needed to be replaced. They informed me it was not covered under warranty and they did not have the parts nor knew when they might get them in. This has been 4 or more months now and the lights stay on more often than they are off. I can’t use…
Had electrical trouble with your 2018 RAM 3500?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the electrical problem on the 2018 RAM 3500?
It's a documented issue but not catastrophic. 122 complaints have been filed. Repairs average $850 and most owners catch it before it causes a breakdown.
At what mileage does the electrical typically fail?
Across the 8 complaints that reported odometer mileage, most electrical failures cluster between 5,500 and 67,000 miles, with the median around 42,000. A quarter of owners report trouble before 5,500; a quarter make it past 67,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $850 for electrical repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to electrical?
No active recalls currently cover electrical issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/RAM/3500.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.