12v Pages - The Engine - MMS300

Features | Identification | Component Locations | How it Works

MMS-3xx Functional Wiring Diagram

MMS-3xx Functional Wiring Diagram

Components

F60: Idle switch
G4: Crankshaft Position Sensor
G6: Fuel pump
G28: Engine Speed Sensor
G39: Oxygen sensor I
G40: Hall Sensor
G61: Knock sensor I
G62: Engine Coolant Temperature (ECT) sensor
G66: Knock sensor II
G69: Throttle valve potentiometer
G70: Mass Air Flow (MAF) sensor
G98: Exhaust Gas Recirculation (EGR) temperature sensor
G108: Oxygen sensor II
J176: Fuel pump relay
J192: Engine Control Module (ECM)
N: Ignition coil for cylinders 1 and 6
N18: EGR frequency valve
N30: Fuel injector, cylinder 1
N31: Fuel injector, cylinder 2
N32: Fuel injector, cylinder 3
N33: Fuel injector, cylinder 4
N71: Idle Air Control (IAC) valve
N80: EVAP carbon canister frequency valve
N83: Fuel injector, cylinder 5
N84: Fuel injector, cylinder 6
N122: Power stage for ignition coils
N128: Ignition coil for cylinders 2 and 4
N156: Intake manifold change-over valve
N158: Ignition coil for cylinders 3 and 5
P: Spark plug connector (6x)
Q: Spark plug (6x)
S17: Fuse for G6
S19: Fuse for diagnostic connector
S64: Circuit breaker for N158, N128, and N
S72: Circuit breaker for N30, N31, N32, N33, N83, and N84
S73: Circuit breaker for G39, G108, N18, N80, and N156
S74: Circuit breaker for G70 and G74

Additional Signals

B8: Throttle valve signal (not pictured)
B9: Road speed signal (not pictured)
B10: Engine speed signal (not pictured)
B11: Fuel consumption signal (not pictured)
B12: Shift lever position signal (not pictured)
B13: Shift point signal (not pictured)
C10: A/C compressor signal (not pictured)
C12: Diagnostic signal for Rapid Data (K circuit)
C13: Diagnostic signal for Rapid Data (L circuit)
C14: Flash code signal

Intake Manifold Change-over Valve N156

N156

The six flaps in the multi-path intake manifold are opened and closed by the intake manifold change-over valve. The change-over valve is a vacuum servo that is electronically activated by the MPI control unit.

The valve is located under the air mass sensor. The valve operates according to engine speed. Above 4100 rpm, the change-over valve opens the six flaps in the intake manifold.

The valve receives 12 volts from fuse S73 (located in the electronic box under the passenger's footwell or underneath the steering column). The MPI control unit supplies ground.

Substitute Function

No substitute functions are available for the change-over valve. If the electrical circuit to the valve is broken or the vacuum valve should fail, the flaps will remain closed.

Self-diagnosis

The ECU recognizes the following:

Short circuit to positive
Open circuit/short to ground