High Speed CAN Communication Bus (+) Low
The CAN-High signal stays below its valid voltage window. Common cause is a short to ground on the CAN-H wire or a transceiver that pulls the line down. The bus stops working until the offending node is isolated.
Affected components
- Can high wire
- Can transceiver
Common causes
- High likelihood: CAN-High shorted to ground
- Medium likelihood: Internal transceiver failure on a node
- Low likelihood: Gateway module routing CAN messages incorrectly
Possible symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Diagnostic notes
- The malfunction indicator lamp may illuminate
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.