GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Underhood Fuse/Relay Center


Object Number: 318669  Size: MF
(1)Aux B
(2)Aux A
(3)Aux B (30 amp)
(4)Lighting (50 amp)
(5)Aux A (30 amp)
(6)Battery (50 amp)
(7)Spare (10 amp)
(8)Fuse puller
(9)Spare (20 amp)
(10)Spare (30 amp)
(11)Ignition A (40 amp)
(12)ECM B (20 amp)
(13)Horn (20 amp)
(14)Air conditioning (10 amp)
(15)Ignition B (50 amp)
(16)Rear defog (30 amp)
(17)Aux fan (30 amp)
(18)ABS (60 amp)
(19)Ignition E (10 amp)
(20)ECM 1 (20 amp)
(21)Engine 1 (20 amp)
(22)Blower (50 amp)
(23)CNG (20 amp)
(24)Stop/Hazard (30 amp)
(25)Not Used
(26)Diode 1
(27)Diode 2
(28)Horn relay
(29)Fuel pump relay
(30)A/C relay
(31)A.I.R. relay
(32)Starter relay
(33)Brake lamp relay
(34)Heated seats/CNG (40 amp)
Figure 2:

AF Electrical Connectors


Object Number: 440527  Size: LF
(1)Cargo Lamp Switch Connector C212
(2)Fuel Gauge Select Switch Connector  C239
(3)High Pressure Lock-off Connector C313 (BLK)
(4)Fuel Temperature Sensor Connector C316 (WHT)
(5)Fuel Pressure Sensor Connector C315 (BLK)
(6)10-way In-line Connector C017 (GRY)
(7)10-way In-line Connector C018 (BLK)
(8)6-way In-line Connector C019 (BLK)
(9)Fuel Gauge Relay Connector C012
(10)Lock-off Relay Connector C011
(11)AF Fuel Pump Relay Connector C007
(12)Ignition Relay Connector C004
(13)AF ECU
(14)AF ECU Connector C001 (BLU)
(15)AF ECU Connector C002 (WHT/CLR)
(16)AF System Ground Location G103
(17)Low Pressure Lock-off Connector C014
(18)Mixture Control Valve Connector C021
(19)Gas Mass Sensor Connector C010
(20)GMS/MCV Assembly
Figure 3:

AF Fuel System


Object Number: 440528  Size: LF
(1)Fuel Gauge Select Switch/Fuel Indicator Lamp Assembly
(2)CNG Fill Valve
(3)CNG Fuel Tank
(4)CNG Fuel Outlet Line
(5)Fuel Pressure Sensor
(6)High Pressure Lock-off Solenoid
(7)CNG Fill Line
(8)High Pressure Regulator Fuel Outlet Line
(9)High Pressure Regulator Fuel Inlet Line
(10)Low Pressure Lock-off Solenoid Inlet Line
(11)Low Pressure Regulator
Figure 4:

AF Engine Components


Object Number: 440530  Size: LF
(1)Air Inlet Resonator
(2)Gas Distribution Adaptor
(3)PCV Make-up Air Hose
(4)Low Pressure Regulator
(5)Low Pressure Lock-off Solenoid
(6)Low Pressure Lock-off Solenoid Fuel Inlet Line
(7)GMS/MCV Assembly