NHTSA Complaint #11506168 — 2017 TOYOTA TUNDRA

Intermittent failure of the integrated trailer brake controller system. System indicates a frequent intermittent fault indicating a wiring or connection issue that disables the signal to activate the trailer brakes resulting in no trailer braking. Vehicle and trailer are available for inspection. I was travelling down a 6% grade mountain (Arizona SR87 MP224) an exhibited a loss of trailer brakes. Taking the trailer to the dealer on flat level service experienced intermittent loss of trailer brakes. Toyota Integrated Brake Controller (IBC) intermittently and randomly indicating a fault in the trailer wiring. •Rapid clicking of the IBC’s electrical relays. •In fault mode, the IBC disables the trailer brakes. •Sometimes the IBC works perfectly for miles and then goes into fault mode for an unknown reason. •Sometimes, the IBC goes into fault mode just plugging the trailer into the electrical socket without even taking the truck out of drive or depressing the brake pedal. •All external trailer lights include turn signals are functioning normally. Examination and diagnosis to date: •Toyota IBC was removed and replaced with a Tekonsha P3 brake controller using a Tekonsha wiring harness adapter to plug directly into the Tundra’s wiring harness used by the original Toyota IBC. The P3 is giving the error as brake circuit short-circuit, overload. •The travel trailer is a 2022 Jayco 212QBW, dual axle. •I brought the trailer to the dealer I purchased it from to have the brake system checked for faults. I’ve attached a copy of receipt from the dealer service department. In short, they examined the following and concluded the issue was with the Tundra. - The trailer wiring was physically examined with no deficiencies. - Trailer connected to the dealer's Chevy Silverado and driven around town with no faults. Toyota dealership claims they can find no fault with their tester. They would not use my 7-pin tester that also exhibits the same problems.