P0642 on Hyundai: How to Diagnose & Fix
Sensor Reference Voltage "A" Circuit Low
1 Hyundai model · 1 documented issue · 1 critical
P0642 on Hyundai by model: symptoms, diagnosis and fix
A sensor inside the EGR valve may have been contaminated with solder flux during supplier manufacturing and can short. Because the EGR valve and crank position sensor share a power circuit, the short can turn on the check-engine light or cause a sudden loss of motive power, which increases the risk of a crash. Applies to: Certain 2024 Hyundai Venue vehicles with the Gamma 1.6L MPI engine built January 12 – March 4, 2024 (2,364 Venues; the recall also covers some 2024 Elantra and Kona). Hyundai campaign 260. Only a Hyundai dealer can confirm whether a specific VIN is included and whether the repair has been done.
How to Fix
Have a Hyundai dealer check the VIN for recall 24V308 (campaign 260). The remedy is replacement of the EGR valve assembly and its gasket at no cost to the owner; Hyundai also offers reimbursement for eligible out-of-pocket repairs of this condition under its plan filed with NHTSA. This is engine-bay electrical and emissions work; no DIY repair or retail part is recommended.
Sources for this issue (2)
P0642 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0642 mean on a Hyundai?
P0642 stands for "Sensor Reference Voltage "A" Circuit Low." The control module detected that the 5-volt sensor reference 'A' supply voltage is below the expected range (typically a short to ground). Multiple sensors sharing this rail are affected. On Hyundai it is documented across 1 model: Venue.
What are the most common causes of P0642?
The most common causes of P0642 are: Short to ground in the reference 'A' circuit, Shorted sensor on the 'A' rail, Damaged/corroded wiring or connectors, Wiring pinched to ground, Internal PCM fault. The specific cause varies by vehicle.
How much does it cost to fix P0642 on a Hyundai?
Repair costs vary widely with the root cause and Hyundai model; each issue on this page carries its own estimate where one is published.
Looking for P0642 on a different make?
View P0642 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.