ENGINE PERFORMANCE – GMC Sierra 2500 1999 – SYSTEM WIRING DIAGRAMS

ENGINE PERFORMANCE

4.3L

4.3L VIN W, Engine Performance Wiring Diagrams (1 of 4) for GMC Sierra 2500 1999

List of elements for 4.3L VIN W, Engine Performance Wiring Diagrams (1 of 4) for GMC Sierra 2500 1999:

• (attached to right rear of throttle body)
• (left rear of engine)
• (on bottom front of engine near crank pulley) crankshaft position sensor
• (on right front side of engine) evaporative emissions canister vent (evap)
• (top right rear of engine) evaporative emissions (evap) canister purge valve
• 1-2 shift sol ctrl
• 2-3 shift sol ctrl
• 3-2 ctrl sol ctrl
• B1 c2
• Cam posit sens rtn
• Cam posit sens sig
• Camshaft position sensor (inside distributor)
• Crank posit sens rtn
• Crank posit sens sig
• Ect sens input
• Egr posit input
• Electronic brake control module (ebcm) (on left side of inner frame)
• Evap
• G114
• G117 (right rear of engine)
• Heated oxygen sensor (ho2s) bank 1 sensor 1 (in exhaust pipe, before catalytic converter)
• Heated oxygen sensor (ho2s) bank 2 sensor 1 (in exhaust pipe, before catalytic converter)
• Heated oxygen sensor (ho2s) bank 2 sensor 2 (in exhaust pipe, after catalytic converter)
• Ho2s sens hi
• Ho2s sens lo
• Hot in run or start
• Iat sens sig
• Idle air control (iac) valve
• Idle air ctrl (iac) a hi
• Idle air ctrl (iac) b lo
• Ign feed
• Inj 1 ctrl
• Inj 2 ctrl
• Inj 3 ctrl
• Inj 4 ctrl
• Inj 5 ctrl
• Inj 6 ctrl
• Instrument cluster system (tachometer)
• Knock sens sig
• Knock sensor (on rear of engine block)
• Map sens input
• Mass air flow sens sig
• Nca
• O2a fuse 15a
• O2b fuse 15a
• Pnk
• Purge valve
• S104
• Sair pump rly
• Sens rtn
• Sens sig
• Tach out
• Tan
• Tcc on/off sol ctrl
• Tcc pwm sol ctrl
• Throttle posit sens
• Trans temp sens sig
• Underhood bussed electrical center
• Vehicle control module (vcm) (on left front of engine compartment)
• Vehicle spd output sig
• Vehicle speed sensor (left rear side of transmission)
• Vehicle speed sensor shield
• Vss input
• Vss rtn
• Vss signal

4.3L VIN W, Engine Performance Wiring Diagrams (2 of 4) for GMC Sierra 2500 1999

List of elements for 4.3L VIN W, Engine Performance Wiring Diagrams (2 of 4) for GMC Sierra 2500 1999:

• 1-2 shift sol
• 2-3 shift sol
• 3-2 control sol
• Automatic transmission
• B6 c3
• C ground
• C10
• C12
• D ign
• D10
• E maf sig
• E12
• E3 c2
• Eng1 fuse 10a
• Exhaust gas recirculation valve (egr) (top front of engine, near thermostat housing)
• Fuel inj 1
• Fuel inj 2
• Fuel inj 3
• Fuel inj 4
• Fuel inj 5
• Fuel inj 6 no.6
• G117 (right rear of engine)
• Heated oxygen sensor (ho2s) bank 1 sensor 2 (in exhaust pipe, after catalytic converter)
• Hot in run or start
• Iat sensor
• Inja fuse 15a
• Injb fuse 15a
• Mass air flow sensor (in air intake duct)
• Nca
• Pnk
• Pnk b
• Pnk d
• Pnk e
• Pnk h
• Pnk j
• Pnk l
• Pressure control solenoid valve
• Red
• S103
• Tan
• Tcc on/off sol
• Tcc pwm sol
• Transmission fluid temperature (tft) sensor (internal)
• Underhood bussed electrical center

4.3L VIN W, Engine Performance Wiring Diagrams (3 of 4) for GMC Sierra 2500 1999

List of elements for 4.3L VIN W, Engine Performance Wiring Diagrams (3 of 4) for GMC Sierra 2500 1999:

• (in engine harn)
• (in fuel tank) fuel tank pressure sensor
• (left rear of engine)
• (right front of engine)
• 5v ref
• Air maxi fuse 30a
• Engine coolant level switch (in coolant reservoir)
• Engine coolant temperature sensor (left rear side of cylinder head)
• Engine oil level switch (right side of oil pan)
• Front axle actuator/ switch
• G114
• G114 (left rear of engine)
• G119
• Hot at all times
• Hot in run or start
• Ign0 fuse 10a
• Ign1 fuse 10a
• Igne fuse 10a
• Instrument cluster
• Left bussed electrical center
• Manifold absolute pressure (map) sensor (top right of engine, near fuel injectors)
• Map
• Mid bussed electrical center c1
• Pnk
• Red
• Red a
• Ref lo
• S102
• S104
• S105
• S106 (in engine harn)
• S107
• S108
• Secondary air injection pump relay (in underhood bussed electrical center)
• Secondary air injection reaction pump (right rear of engine compt)
• Secondary air injection reaction valve solenoid (right rear of engine compt)
• Service engine soon indicator
• Temp
• Throttle position (tp) sensor (on throttle body assembly)
• Underhood bussed electrical center

4.3L VIN W, Engine Performance Wiring Diagrams (4 of 4) for GMC Sierra 2500 1999

List of elements for 4.3L VIN W, Engine Performance Wiring Diagrams (4 of 4) for GMC Sierra 2500 1999:

• (left frame rail near body mount)
• (right rear of engine)
• 12v battery fused
• 4wd fuse 15a
• 4wd low ind sig
• 5v ref voltage
• 5v return
• A/c comp rly ctrl
• A/c rec sw
• A/c request signal
• A/c system
• Automatic transfer case control module (above headlight switch)
• Body control module (below steering column)
• Brake fuse 10a
• Brake switch input
• C11
• Check eng lp ind out
• Clutch pedal position switch (top of clutch pedal)
• Coil wire
• Comp cycling sw
• Coolant lev
• Cpp sw input
• Cruise control system
• Cruise control system, body computer system (vehicle speed signal)
• Cruise ctrl sig-eng
• Data link connector (below steering column)
• Distributor
• Ecm1 fuse 10a
• Ecmb fuse 20a
• Egr valve cntrl
• Est output sig
• Evap sol purge ctrl
• Four whl dr sig lo
• Fuel lev sensor
• Fuel pump relay
• Fuel pump rly ctrl
• Fuel pump/ level sensor
• Fused output
• G117
• G119 (right front of engine)
• G402
• Gen term l
• Ground
• Hot at all times
• Hot in run and start
• Ign
• Ign timing sig.
• Ignition coil (top right rear of engine)
• Ignition control module (right side, top of engine)
• Ignition feed
• Left bussed electrical center
• Manual 4wd
• Mid bussed electrical center c1
• Oil level signal
• Park/neutral position switch (left side of transmission)
• Pnk
• Pnk a
• Power
• Press ctrl sol hi
• Press ctrl sol lo
• Prndl a
• Prndl b
• Prndl c
• Prndl p
• Recirc door sig
• Red
• S102
• S103
• S199
• Sensor ground
• Serial data
• Serial data sig
• Sp205 (behind headlamp switch)
• Starting/char- ging system
• Stoplamp switch (top of brake pedal bracket)
• Tach. sig.
• Trans press sig-bit 1
• Trans press sig-bit 2
• Trans press sig-bit 3
• Transfer case switch
• Underhood bussed electrical center
• Vcm ground
• Vehicle control module (vcm) (on left front of engine compartment)
• Vss sig
• W/ atc

4.8L

4.8L VIN V, Engine Performance Wiring Diagrams (1 of 4) for GMC Sierra 2500 1999

List of elements for 4.8L VIN V, Engine Performance Wiring Diagrams (1 of 4) for GMC Sierra 2500 1999:

• (below steering column) data link connector
• (lower right rear of engine) crankshaft position sensor
• (right rear of engine)
• +5v
• 1995 vftc
• 3-2 ss
• Body control module (below steering column)
• Brk sw
• C10
• C11
• C12
• Ckp
• Cls 2 data
• Clutch sw
• Cmp
• Coolant lev
• D10
• E12
• Ecm1 fuse 10a
• Ecmb fuse 20a
• Ect sig
• Egr input
• G117
• G117 (right rear of engine) c
• Gnd
• Ho2s hi
• Ho2s lo
• Hot at all times
• Hot in run and start
• Ign
• Ign 0 fuse 10a
• Inj1
• Inj2
• Inj3
• Inj4
• Inj5
• Inj6
• Inj7
• Inj8
• Inja fuse 15a
• Injb fuse 15a
• Injectors
• Ks signal
• Left bussed electrical center
• O2a fuse 15a
• O2b fuse 15a
• Oil lev
• Pnk
• Pnk b
• Powertrain control module (left front of engine compt)
• Prnd a
• Prnd b
• Prnd p
• Range b
• Range c
• Red
• Ref low
• S103
• Sens gnd
• Sens rtn
• Sp205 (behind headlamp switch)
• Tan
• Tan tan
• Underhood bussed electrical center

4.8L VIN V, Engine Performance Wiring Diagrams (2 of 4) for GMC Sierra 2500 1999

List of elements for 4.8L VIN V, Engine Performance Wiring Diagrams (2 of 4) for GMC Sierra 2500 1999:

• (left front of engine)
• (left rear of engine)
• (left rear of engine) g114
• (not used)
• 1995 vftc c
• Air maxi fuse 30a c7
• Ecm b fuse 20a
• Engine coolant level switch (in coolant reservoir)
• Engine coolant temperature sensor (left front of cylinder head)
• Engine oil level switch (right side of oil pan)
• Front knock sensor (under intake manifold)
• Fuel pump relay
• Fuel pump/ level sensor (in fuel tank)
• G104
• G110
• G114 (left rear of engine)
• G117 (right rear of engine)
• G402 (left frame body mount bracket)
• Heated oxygen sensor (bank 1 sensor 1) (left exh pipe before converter)
• Heated oxygen sensor (bank 1 sensor 2) (left exh pipe after converter)
• Heated oxygen sensor (bank 2 sensor 1) (right exh pipe (before converter)
• Heated oxygen sensor (bank 2 sensor 2) (right exh pipe after converter)
• Hot at all times
• Hot in run and start
• Ign e fuse 10a c2
• Nca
• Park/neutral position switch (left side of transmission)
• Pnk
• Rear knock sensor (under intake manifold)
• Red
• S103
• S104
• S104 (in engine harness)
• S108
• Secondary air injection reaction pump (right rear of engine compt)
• Secondary air injection reaction relay (in underhood bussed electrical center)
• Secondary air injection reaction solenoid (right rear of engine compt)
• Tan
• Throttle position sensor (on throttle body assy)
• Underhood bussed electrical center

4.8L VIN V, Engine Performance Wiring Diagrams (3 of 4) for GMC Sierra 2500 1999

List of elements for 4.8L VIN V, Engine Performance Wiring Diagrams (3 of 4) for GMC Sierra 2500 1999:

• 1-2 sol
• 2-3 sol
• 3-2 sol
• A/t fluid pressure manual valve position switch
• Automatic transaxle
• Brake fuse 10a
• Camshaft position sensor (top center rear of engine)
• Clutch pedal position switch (top of pedal bracket)
• Evap canister purge valve (top right rear of engine)
• Evap canister vent valve (right front side of engine)
• Exhaust gas recirculation valve (top right front of engine)
• Fuel tank pressure sensor (in fuel tank)
• G117 (right rear of engine)
• Gnd
• Hot in run
• Hot in run and start 1995 vftc c
• Iat sensor
• Ign
• Ign0 fuse 10a
• Left bussed elec- trical center
• Manifold absolute pressure sensor (top rear of engine)
• Mass airflow sensor (in air intake duct)
• Mid bussed electrical center
• N pnk
• P red
• Pc sol valve
• Pnk
• Pnk a
• Pnk b
• Pnk d
• Red
• Red e
• Red/
• Rev
• S103
• Signal
• Stop- lamp switch (top of brake pedal)
• Tan
• Tan b
• Tcc pwm sol
• Tcc sol
• Tft sensor
• Underhood bussed electrical center c2
• Vehicle speed sensor (left rear of transmission)
• Vss adapter (4wd) (left side of trans)

4.8L VIN V, Engine Performance Wiring Diagrams (4 of 4) for GMC Sierra 2500 1999

List of elements for 4.8L VIN V, Engine Performance Wiring Diagrams (4 of 4) for GMC Sierra 2500 1999:

• (in engine harness)
• (left front of engine) g110
• (left rear of engine) g114
• 1-2 ss
• 1995 vftc c
• 2-3 ss
• 4wd low
• A/c clu
• A/c req
• A/c system
• A10
• Air pump
• Anti-lock brake system (speed signal)
• Automatic transfer case control module (above c3 headlight switch)
• Cruise control system
• Cruise control, instrument cluster systems (speed signal)
• Cruise eng
• Ctrl
• Cyc sw in
• Egr ctrl
• Egr gnd
• Eng1 fuse 10a
• Evap canp
• Evap vent
• Front axle switch
• Frt axle sw
• Fuel lev
• Fuel pmp
• Fuel sig ctrl
• G117 (right rear of engine)
• Gen l
• Gnd
• Hot in run and start
• Iac coil hi
• Iac coil lo
• Iat sig
• Idle air control valve (top of throttle body)
• Ign
• Ign ctrl
• Ign feed
• Ign1 fuse 10a
• Ignition coils
• Instrument cluster
• Left bussed electrical center
• Maf sig
• Malfunction indicator lamp
• Map sig
• Mil ctrl
• Nca
• Nca nca
• Pc sol hi
• Pc sol lo
• Pnk
• Pnk d
• Powertrain control module (left front of engine compt)
• Prnd c
• Recirc door
• Recirc sw
• Red
• Red c
• Ref lo
• Ref low
• Rpm out
• S103
• S151
• S152
• S153
• S154
• S157
• Sens gnd
• Spark plug
• Starting/charging system
• Tan
• Tcc pwm
• Tcc sol
• Tft sens sig
• Tp sig
• Trans rng a
• Transfer case switch
• Underhood bussed electrical center
• Vss high
• Vss low
• Vss out
• W/ atc
• W/ manual 4wd

5.3L

5.3L VIN T, Engine Performance Wiring Diagrams (1 of 4) for GMC Sierra 2500 1999

List of elements for 5.3L VIN T, Engine Performance Wiring Diagrams (1 of 4) for GMC Sierra 2500 1999:

• (below steering column) data link connector
• (lower right rear of engine) crankshaft position sensor
• (right rear of engine)
• +5v
• 1995 vftc
• 3-2 ss
• Body control module (below steering column)
• Brk sw
• C10
• C11
• C12
• Ckp
• Cls 2 data
• Clutch sw
• Cmp
• Coolant lev
• D10
• E12
• Ecm1 fuse 10a
• Ecmb fuse 20a
• Ect sig
• Egr input
• G117
• G117 (right rear of engine) c
• Gnd
• Ho2s hi
• Ho2s lo
• Hot at all times
• Hot in run and start
• Ign
• Ign 0 fuse 10a
• Inj1
• Inj2
• Inj3
• Inj4
• Inj5
• Inj6
• Inj7
• Inj8
• Inja fuse 15a
• Injb fuse 15a
• Injectors
• Ks signal
• Left bussed electrical center
• O2a fuse 15a
• O2b fuse 15a
• Oil lev
• Pnk
• Pnk b
• Powertrain control module (left front of engine compt)
• Prnd a
• Prnd b
• Prnd p
• Range b
• Range c
• Red
• Ref low
• S103
• Sens gnd
• Sens rtn
• Sp205 (behind headlamp switch)
• Tan
• Tan tan
• Underhood bussed electrical center

5.3L VIN T, Engine Performance Wiring Diagrams (2 of 4) for GMC Sierra 2500 1999

List of elements for 5.3L VIN T, Engine Performance Wiring Diagrams (2 of 4) for GMC Sierra 2500 1999:

• (left front of engine)
• (left rear of engine)
• (left rear of engine) g114
• (not used)
• 1995 vftc c
• Air maxi fuse 30a c7
• Ecm b fuse 20a
• Engine coolant level switch (in coolant reservoir)
• Engine coolant temperature sensor (left front of cylinder head)
• Engine oil level switch (right side of oil pan)
• Front knock sensor (under intake manifold)
• Fuel pump relay
• Fuel pump/ level sensor (in fuel tank)
• G104
• G110
• G114 (left rear of engine)
• G117 (right rear of engine)
• G402 (left frame body mount bracket)
• Heated oxygen sensor (bank 1 sensor 1) (left exh pipe before converter)
• Heated oxygen sensor (bank 1 sensor 2) (left exh pipe after converter)
• Heated oxygen sensor (bank 2 sensor 1) (right exh pipe (before converter)
• Heated oxygen sensor (bank 2 sensor 2) (right exh pipe after converter)
• Hot at all times
• Hot in run and start
• Ign e fuse 10a c2
• Nca
• Park/neutral position switch (left side of transmission)
• Pnk
• Rear knock sensor (under intake manifold)
• Red
• S103
• S104
• S104 (in engine harness)
• S108
• Secondary air injection reaction pump (right rear of engine compt)
• Secondary air injection reaction relay (in underhood bussed electrical center)
• Secondary air injection reaction solenoid (right rear of engine compt)
• Tan
• Throttle position sensor (on throttle body assy)
• Underhood bussed electrical center

5.3L VIN T, Engine Performance Wiring Diagrams (3 of 4) for GMC Sierra 2500 1999

List of elements for 5.3L VIN T, Engine Performance Wiring Diagrams (3 of 4) for GMC Sierra 2500 1999:

• 1-2 sol
• 2-3 sol
• 3-2 sol
• A/t fluid pressure manual valve position switch
• Automatic transaxle
• Brake fuse 10a
• Camshaft position sensor (top center rear of engine)
• Clutch pedal position switch (top of pedal bracket)
• Evap canister purge valve (top right rear of engine)
• Evap canister vent valve (right front side of engine)
• Exhaust gas recirculation valve (top right front of engine)
• Fuel tank pressure sensor (in fuel tank)
• G117 (right rear of engine)
• Gnd
• Hot in run
• Hot in run and start 1995 vftc c
• Iat sensor
• Ign
• Ign0 fuse 10a
• Left bussed elec- trical center
• Manifold absolute pressure sensor (top rear of engine)
• Mass airflow sensor (in air intake duct)
• Mid bussed electrical center
• N pnk
• P red
• Pc sol valve
• Pnk
• Pnk a
• Pnk b
• Pnk d
• Red
• Red e
• Red/
• Rev
• S103
• Signal
• Stop- lamp switch (top of brake pedal)
• Tan
• Tan b
• Tcc pwm sol
• Tcc sol
• Tft sensor
• Underhood bussed electrical center c2
• Vehicle speed sensor (left rear of transmission)
• Vss adapter (4wd) (left side of trans)

5.3L VIN T, Engine Performance Wiring Diagrams (4 of 4) for GMC Sierra 2500 1999

List of elements for 5.3L VIN T, Engine Performance Wiring Diagrams (4 of 4) for GMC Sierra 2500 1999:

• (in engine harness)
• (left front of engine) g110
• (left rear of engine) g114
• 1-2 ss
• 1995 vftc c
• 2-3 ss
• 4wd low
• A/c clu
• A/c req
• A/c system
• A10
• Air pump
• Anti-lock brake system (speed signal)
• Automatic transfer case control module (above c3 headlight switch)
• Cruise control system
• Cruise control, instrument cluster systems (speed signal)
• Cruise eng
• Ctrl
• Cyc sw in
• Egr ctrl
• Egr gnd
• Eng1 fuse 10a
• Evap canp
• Evap vent
• Front axle switch
• Frt axle sw
• Fuel lev
• Fuel pmp
• Fuel sig ctrl
• G117 (right rear of engine)
• Gen l
• Gnd
• Hot in run and start
• Iac coil hi
• Iac coil lo
• Iat sig
• Idle air control valve (top of throttle body)
• Ign
• Ign ctrl
• Ign feed
• Ign1 fuse 10a
• Ignition coils
• Instrument cluster
• Left bussed electrical center
• Maf sig
• Malfunction indicator lamp
• Map sig
• Mil ctrl
• Nca
• Nca nca
• Pc sol hi
• Pc sol lo
• Pnk
• Pnk d
• Powertrain control module (left front of engine compt)
• Prnd c
• Recirc door
• Recirc sw
• Red
• Red c
• Ref lo
• Ref low
• Rpm out
• S103
• S151
• S152
• S153
• S154
• S157
• Sens gnd
• Spark plug
• Starting/charging system
• Tan
• Tcc pwm
• Tcc sol
• Tft sens sig
• Tp sig
• Trans rng a
• Transfer case switch
• Underhood bussed electrical center
• Vss high
• Vss low
• Vss out
• W/ atc
• W/ manual 4wd