What Does U0016 Mean?
The CAN Low (negative) wire voltage on the medium-speed network is below normal operating range. This indicates a short to ground condition that disrupts network communication between modules.
Safety Warning
Multiple vehicle systems may become inoperative including safety systems like ABS, traction control, and airbag systems. Vehicle operation may be severely impaired.
Common Causes
40%
CAN Low wire shorted to ground in harness
25%
Water intrusion causing corrosion and ground short at connectors
20%
Pinched or damaged wire from bodywork or previous repairs
10%
Failed module with internal short to ground on CAN Low circuit
5%
Aftermarket accessory installation causing wire damage
Diagnostic Steps
1
Step 1: Disconnect modules one at a time while monitoring CAN Low voltage to isolate the short location
2
Step 2: Measure resistance from CAN Low circuit to ground with all modules disconnected (should be high resistance)
3
Step 3: Inspect harness for pinch points, wear marks, or areas where wire may contact grounded metal
4
Step 4: Check for water intrusion in connectors, especially in areas exposed to weather or fluid leaks
5
Step 5: Use oscilloscope to verify CAN signal quality and identify abnormal waveforms indicating short location
Estimated Repair Cost
$200 - $1,800
Parts + labor, varies by vehicle and location
The CAN Low (negative) wire voltage on the medium-speed network is below normal operating range. This indicates a short to ground condition that disrupts network communication between modules.
The most common cause of U0016 (Medium Speed CAN Communication Bus (-) Low) is: CAN Low wire shorted to ground in harness
Typical repair costs for U0016 range from $200 to $1,800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Multiple vehicle systems may become inoperative including safety systems like ABS, traction control, and airbag systems. Vehicle operation may be severely impaired.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U0016 to identify the root cause.
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Quick Info
Category
Network
System
Network Communication System
Difficulty
Type
Generic (SAE)
Recommended Tools
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