U0067 — Vehicle Communication Bus E (+) Low

Causes

• Open or short in Bus E wiring (short to ground or battery)
• Faulty CAN/LIN transceiver or control module
• Damaged or corroded connectors or grounds on the bus
• Failed bus termination resistor(s)
• Low vehicle battery or poor battery connections
• Aftermarket electronics or recent repairs that disturbed the bus wiring

Symptoms

• Multiple module warning messages or lamp illumination
• Loss of instrument cluster, radio, or HVAC controls
• Intermittent or permanent loss of features controlled by bus modules
• No communication with one or more control modules on a scan tool
• Erratic or degraded vehicle behavior if critical modules are affected

What to check

• Connect a professional scan tool and read all network-related U-codes and module presence
• Check battery voltage and battery terminal condition (engine off and cranking)
• Visually inspect wiring harnesses, connectors, and grounds related to Bus E
• Look for recent service or aftermarket installations that tie into vehicle networks
• Check for correct termination resistance across the bus (typ. two 60 ohm or 120 ohm equivalent)
• Use backprobe or harness pinouts to measure bus voltages and continuity

Signal parameters

• Nominal recessive CAN voltage ≈ 2.5 V on both bus lines
• Dominant CAN: CAN High rises toward ≈ 3.5 V, CAN Low drops toward ≈ 1.5 V (differential ≈ 2 V)
• Expected differential voltage: 0 V (short/fault) to ≈ 2 V during communication
• Termination resistance typically ≈ 60 ohm (between CAN_H and CAN_L at one end) or 120 ohm total
• LIN bus typical idle voltage ≈ battery voltage via pull-up; signaling differs from CAN

Similar codes

Causes

• Open or short in Bus E wiring (short to ground or battery)
• Faulty CAN/LIN transceiver or control module
• Damaged or corroded connectors or grounds on the bus
• Failed bus termination resistor(s)
• Low vehicle battery or poor battery connections
• Aftermarket electronics or recent repairs that disturbed the bus wiring

Symptoms

• Multiple module warning messages or lamp illumination
• Loss of instrument cluster, radio, or HVAC controls
• Intermittent or permanent loss of features controlled by bus modules
• No communication with one or more control modules on a scan tool
• Erratic or degraded vehicle behavior if critical modules are affected

What to check

• Connect a professional scan tool and read all network-related U-codes and module presence
• Check battery voltage and battery terminal condition (engine off and cranking)
• Visually inspect wiring harnesses, connectors, and grounds related to Bus E
• Look for recent service or aftermarket installations that tie into vehicle networks
• Check for correct termination resistance across the bus (typ. two 60 ohm or 120 ohm equivalent)
• Use backprobe or harness pinouts to measure bus voltages and continuity

Signal parameters

• Nominal recessive CAN voltage ≈ 2.5 V on both bus lines
• Dominant CAN: CAN High rises toward ≈ 3.5 V, CAN Low drops toward ≈ 1.5 V (differential ≈ 2 V)
• Expected differential voltage: 0 V (short/fault) to ≈ 2 V during communication
• Termination resistance typically ≈ 60 ohm (between CAN_H and CAN_L at one end) or 120 ohm total
• LIN bus typical idle voltage ≈ battery voltage via pull-up; signaling differs from CAN

Similar codes

Causes

• Open or short in Bus E wiring (short to ground or battery)
• Faulty CAN/LIN transceiver or control module
• Damaged or corroded connectors or grounds on the bus
• Failed bus termination resistor(s)
• Low vehicle battery or poor battery connections
• Aftermarket electronics or recent repairs that disturbed the bus wiring

Symptoms

• Multiple module warning messages or lamp illumination
• Loss of instrument cluster, radio, or HVAC controls
• Intermittent or permanent loss of features controlled by bus modules
• No communication with one or more control modules on a scan tool
• Erratic or degraded vehicle behavior if critical modules are affected

What to check

• Connect a professional scan tool and read all network-related U-codes and module presence
• Check battery voltage and battery terminal condition (engine off and cranking)
• Visually inspect wiring harnesses, connectors, and grounds related to Bus E
• Look for recent service or aftermarket installations that tie into vehicle networks
• Check for correct termination resistance across the bus (typ. two 60 ohm or 120 ohm equivalent)
• Use backprobe or harness pinouts to measure bus voltages and continuity

Signal parameters

• Nominal recessive CAN voltage ≈ 2.5 V on both bus lines
• Dominant CAN: CAN High rises toward ≈ 3.5 V, CAN Low drops toward ≈ 1.5 V (differential ≈ 2 V)
• Expected differential voltage: 0 V (short/fault) to ≈ 2 V during communication
• Termination resistance typically ≈ 60 ohm (between CAN_H and CAN_L at one end) or 120 ohm total
• LIN bus typical idle voltage ≈ battery voltage via pull-up; signaling differs from CAN

Similar codes