U0068
Vehicle Communication Bus E (+) High
Vehicle communication network
Generic OBD-II
Medium
What it means
U0068 means the positive wire of the vehicle's Bus E communication network is reading too high, usually because it is shorted to a power source or a module is driving it high. Modules on Bus E can lose communication, dropping features offline and setting warning lights. It is an electrical fault in the bus wiring or one of the connected modules.
Medium
Can I keep driving? Often driveable, but a high bus voltage can knock modules on Bus E offline with warning lights and lost features, and limp mode if a powertrain module is involved — diagnose promptly.
Common symptoms
What you'll notice
- One or more modules on Bus E dropping offline
- Multiple warning lights on together
- Features tied to this bus not working
- Communication errors reported when scanned
Common causes
Most likely first
- Bus E (+) wire shorted to battery voltage or another power feedLikely
- Chafed wiring contacting a powered circuitCommon
- Corroded connector raising circuit voltageCommon
- A failed module driving the bus highLess often
How to diagnose & fix
Work through it in order
- Scan all modules and record which Bus E modules are affected.
- Inspect the Bus E (+) wiring for chafing and shorts to a power source.
- Measure bus voltage and check for a short to power.
- Disconnect suspect modules one at a time to find one driving the bus high.
- Repair the wiring or replace the faulty module, clear codes, and retest.
FAQ
Quick answers
Is it safe to drive with U0068?+
A high bus voltage can silence the modules on Bus E. The driving impact depends on which systems live on this bus — get it checked, especially if brake or powertrain modules are affected.
Can I just clear U0068?+
It returns until the short-to-power or failed module is repaired. Clearing does not fix the electrical fault.
Related codes
Often seen with U0068
Read & clear U0068 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX