Vehicle Communication Bus D (+) High
What it means
U0059 means the plus (+) side of vehicle communication bus "D" is reading higher than it should — usually a short to battery voltage or another powered wire, or a module driving the line high. With the bus voltage stuck high, modules on that bus can't communicate and go offline. The impact depends on which modules share bus D; the fault is typically a shorted wire, a damaged connector, or a failed module.
Can I keep driving? Depends on what shares bus D — the car may drive normally or may lose features and light warnings; if a powertrain module is on this bus you could see limp mode.
Common symptoms
What you'll notice
- Warning lights on with multiple lost-communication codes
- One or more modules unresponsive to a scan tool
- Features handled by bus-D modules stop working
- Cluster warnings or gauges affected
Common causes
Most likely first
- (+) bus wire shorted to battery or another powered circuitLikely
- Damaged connector or harness contacting a powered wireCommon
- A failed module driving the bus highCommon
- Corrosion bridging the bus to a power sourceLess often
How to diagnose & fix
Work through it in order
- Scan all modules and find which lost communication on bus D.
- Check the (+) bus wire for a short to power; inspect harness routing near powered circuits.
- Isolate a failed module by disconnecting suspects one at a time.
- Repair the short or replace the faulty module.
- Clear codes and confirm normal communication.
FAQ
Quick answers
Is it safe to drive with U0059?+
Can I just clear U0059?+
Related codes
Often seen with U0059
Read & clear U0059 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.