CAN Communication Bus Fault? Now that’s generic. The Bus is the communications network used by many vehicles to make all the modules work together. When you have a bus fault code, you have to find out what part of the system is causing the issue. Follow this Real Fix to see how this was done on this 2006 Ford F350 Super Duty.
Vehicle
2006 Ford Cab & Chassis F350 Super Duty 5.4
Title
Check Engine Light Is On, U1900, Replaced Anti-Lock Brake Traction Control Module
Complaint
The customer states the check engine light is on.
Cause
Connected a scan tool and found code U1900 CAN Communication Bus Fault. There was no communication available with the anti-lock brake traction control module. Performed a visual inspection of the anti-lock brake system, wiring harnesses, speed sensors and detected no obvious faults. Performed a visual inspection of the anti-lock brake traction control module and found no obvious faults. Disconnected the anti-lock brake traction control module connectors, visually inspected the connectors and terminals and found no obvious signs of loose pins, corrosion or damage. Visually inspected the anti-lock brake traction control module wiring harness and found no obvious signs of damage. Used a multi-meter to check for the presence of shorts or opens in the anti-lock brake traction control module wire circuits and found that none were present. Used the multi-meter to check for the presence of power and ground at the anti-lock brake traction control module harness connector and found that both were present. The result of these tests verified the anti-lock brake traction control module was faulty.
Correction
Replaced the anti-lock brake traction control module, cleared codes, performed a road test and verified the vehicle operated properly. The check engine light did not illuminate and no fault codes returned.