Models Affected: 2009 through 2012 Model Year GM 8.1 Propane Vision Models ISSUE Bus will start if fuel door is either open or closed if the circuit is broken by a blown fuse or tripped circuit breaker. CORRECTIVE ACTION ---- Update fuel fill door wiring circuit to eliminate fuse or circuit breaker so bus will not start when the fuel fill door is open. PROCEDURE WARNING: Always follow all Federal, State, And Local and Shop safety standards and use proper safety equipment when performing these procedures. Observe all safety precautions to secure the bus from rolling. 1. Park the bus on a level surface, apply parking brakes, turn off engine and remove keys. Chock wheels. 2. Disconnect batteries Note; When disconnecting the batteries, remove the negative cable first. 3. Remove chassis Power Distribution Unit (PDU) cover by unscrewing two thumb screws. The thumb screws are located at the top of each side of the cover. Thumb screws. Cover is located lower center of dash. --S E R V I C E B U L L E T I N----S 1 1 T C----- Page 1 of 6
4. Locate FUEL DOOR + fuse shown on PDU decal on reverse side of PDU cover removed in previous step. Remove fuse (no longer required). 5. Locate RED wire labeled FUEL DOOR + that is connected to this fuse position. Remove this wire and cut off terminal. Crimp on new terminal #01353630 and connect to PDU ground stud. (Torque ground stud nut 11 to 15 FT LBS) See examples below of PDU layouts with single zone and dual zone multiplex. PDU Ground Stud Single Zone Multiplex Chassis PDU Layout Shown Above: PDU Ground Stud FUEL DOOR + Fuse FUEL DOOR + Fuse Dual Zone Multiplex Chassis PDU Layout Shown Above: Page 2 of 6
6. On buses with a Single Zone Multiplex locate the RED wire in connector C703 cavity position 26. This circuit routes to a splice located approximately two inches from multiplex module connectors A thru D. This circuit will be labeled AC-102 or AC-102A. Cut this side of the circuit from the splice. Tape splice where circuit was removed. Re-splice the removed circuit to the Tan wire AC-016 (Vandal Lock) located in module connector C cavity position 16 using butt splice terminal # 01596196. This terminal has an 18/22 gauge cavity and a 14/16 gauge cavity. Use the 14/16 cavity for the two circuits spliced together. See examples below of Chassis PDU layout with single zone multiplex. 7. Reconnect batteries Note, connect positive cable first. Switch ignition key on. Verify with fuel fill door open that A Zone, Port 3, Input 8 LED is ON. Verify engine starter will NOT engage with fuel fill door opened. Replace chassis PDU cover. Update complete. Connector C703 Cavity 26 Connector C Cavity 16 Page 3 of 6
8. On buses with a Dual Zone Multiplex locate the RED wire in module connector C cavity position 11. This circuit will be labeled FUEL DOOR IN10. Remove circuit from connector. Butt splice FUEL DOOR IN10 circuit to wire assembly #10023714. Route the wire assembly following along the PDU harness over the steering column to the body electrical panel area under the driver side window. Secure assembly with tie cable # 00059567. See PDU layout with dual zone multiplex below. Dual Zone Multiplex Chassis PDU Layout Shown Below: Connector C Cavity 11 Page 4 of 6
9. On buses with a Dual Zone Multiplex insert terminal end on wire assembly from previous step into body control module connector A cavity 13. If optional wire is already in cavity 13 DO NOT remove. Cut terminal off supplied assembly from previous step and splice to existing wire in cavity 13 using butt splice terminal # 01596196. This terminal has an 18/22 gauge cavity and a 14/16 gauge cavity. Use the 14/16 cavity for the two circuits spliced together. Dual Zone Multiplex Body Electrical Panel Layout Shown Below: Connector A Cavity 13 Page 5 of 6
10. Reconnect batteries Note, connect positive cable first. Switch ignition on. Verify with fuel fill door open that B Zone, Port 1, Input 7 LED is ON. Verify engine starter will NOT engage with fuel door opened. Replace chassis PDU cover. Update complete. PARTS PART NUMBER 01353630 01596196 00059567 10023714 NPN QUANTITY 1 1 8 1 DESCRIPTION Terminal, Eyelet, 3/8, 18-20 GA, Insulated Terminal, Butt Conn, Step Down, 18-22/14-16 Tie, Cable, 18 LB Harness, Wrg, Fuel Fill Door Switch S11TC Black Electrical Tape TOOLS Wire Cutters Wire Strippers Crimper for Butt Connector Tool Terminal Removal Deutsch (BB # 00015909) Tool Terminal Removal Narrow Pick (BB # 02084515) Page 6 of 6