Controller Area Network (CAN) Diagnostic Simulator

Vehicle Voltages are read key on. Resistance is read key off. Never both at once.

CAN_H

RED CAN_H·BLK SIG GND

DMM

≈2.70V

Known good ≈2.70 V

CAN_L

RED CAN_L·BLK SIG GND

DMM

≈2.20V

Known good ≈2.20 V

Diff

RED CAN_H·BLK CAN_L

DMM

≈0.50V

Known good ≈0.50 V

Term

RED CAN_H·BLK CAN_L

DMM

--Ω

Known good 60 Ω

Module communicating Communication lost Traffic on the wire 120Ω terminator Crossing, not connected

Normal CAN bus operation. On a meter CAN_H averages about 2.7V and CAN_L about 2.2V, giving roughly 0.5V differential. Termination reads 60Ω.