Date: 201510
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground ZZZ
Aircraft component: Checklists
Component problem: Design
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Distraction; Communication Breakdown; Confusion; Workload
Second reporter function: Pilot Flying; Captain
Anomaly: Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Taxiway
Detector: Person Air Traffic Control; Person Flight Crew
When detected: Taxi
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Contributing factors: Procedure; Company Policy; Human Factors
Primary problem: Company Policy

Narrative: Taxing out we contact ramp for push and we were told by ramp to expect runway XXL or XXR. We had expected Runway XY and had everything set up for that runway. So on push back we change the runway to XXR. We decided to start both engines due to quick taxi to XXR. We contact ground and receive a clearance to taxi to XXL via G and WA. Then ground informs us that we exited the wrong exit. I did not notice that until he said something as I was heads down doing a runway change and talking on [the] radio. I noticed that the Captain had turned the correct direction and was heading the correct way when I started the change. We were on the green line and I think when he got to the next line thought it was AN. So there was a bit of confusion. Ground says no problem and we proceed down G. I am heads down again as I have to get new numbers change runway make sure everything is correct and run the before takeoff checklist. The new procedures and checklist are still cumbersome for me as a reserve pilot I have only had a handful of trips using it and find that it takes me out of a lot of the taxi. As I am making the changes the Captain slows and asks about the signage. We are at the intersection of G; B4; and WA. Ground asks us where we are going and I respond WA XXL. They say to go through the WA pad to XXL. We had missed the turn to WA. I had no idea until the Captain slowed as I was trying to get all the changes and checklists done. We continued through the pad with no further problems and departed.I feel that the new procedures with the long taxi checklist are cumbersome. Although that will get a little better with time and familiarity. It still takes me out of the loop for large portions of the taxi. Runway changes are now a bigger problem as there is a lot more to do with getting new numbers making changes and running the checklist again and possible starting an engine. I guess we should have just taxied to the hold pad stopped and done all the changes before continuing.


Second narrative: We received numerous runway changes on taxi out. Ground told us to turn left onto Golf then WA for XXL. I ended up missing WA because I was confused by the signage that directed B4 to WA. This sign refers to the WA run up area. I made the mistake of dividing my time inside and outside watching the FO make changes to the FMC when I should have been completely focused on taxing the airplane. ATC then cleared us to taxi through the WA run up area to intercept WA.


Synopsis: A B737 crew reported a ground taxiway incursion while taxiing for takeoff because the First Officer was heads down with checklist duties; out of the situational awareness loop and the Captain is not aware of checklist status.