B767-300 and 300 ER
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 240; Flight Crew Total 11700; Flight Crew Type 860
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft; Human Factors
During preflight; I checked all the CB panels. I saw that there was a CB collared behind the First Officer (FO) seat; but it looked like the normal collars that are used on items that have been deactivated. So I thought nothing of it.We pushed back; started both engines; shut down the APU and taxied out on two engines.Then a weather delay caused us to shut an engine down to save gas. The moment we shutdown the number two engine; we lost all kinds of things. And got some odd EICAS messages. Then the avionics stopped cooling properly. We called [Maintenance]; but after a while they told us to return to the gate. Eventually it became clear that the bus ties were not working.We got back to the gate and a mechanic found that the collared CB behind the FO seat was the 'bus tie enable' CB. He said that whoever put that collar on should have used the red collars that have 'remove before flight' ribbons on it. The mechanic took it very seriously and said he was going to follow up with proper reports and with the Maintenance training department.
B767-300 First Officer reported returning to the gate after experiencing loss of a number of components following an engine shutdown during taxi. Maintenance found a bus tie circuit breaker was improperly collared.