MG MG6 Series 2011 Service Manual page 283

Engine Fuel & Management System
• Observe the correct torque tightening value when
installing the HO2S.
• Do not subject theHO2S to mechanical shocks.
• TheHO2S may be contaminated if fuel with added lead
is used.
• Avoid using silicone sprays around the sensors or inlet
manifold.
Brake Switch
The brake switch is a Hall effect device consisting of an
inner sensor in an outer mounting sleeve. To ensure correct
orientation, the sensor is keyed to the mounting sleeve and
the mounting sleeve is keyed to the pedal mounting bracket
on the engine bulkhead. Mating serrations hold the sensor in
position in the mounting sleeve.
The brake pedal is installed on a pivot shaft in the pedal
mounting bracket. A clevis pin and clip connect the input rod
of the brake servo to the brake pedal. A tang on the end of
the brake pedal activates the 'instant make and break' switch.
The brake switch includes two separate circuits, one normally
open and one normally closed, connecting to ground. The two
circuits are referred to as 'brake main' and 'brake safety'.
Clutch Switch - Manual Transmission Only
Version 2.0
The clutch switch is identical to the brake switch. It is located
on the pedal box assembly connected to the engine bay harness
using connector EB059.
The clutch switch consists of an inner sensor in an outer
mounting sleeve. To ensure correct orientation, the sensor
is keyed to the mounting sleeve and the mounting sleeve is
keyed to the pedal mounting bracket. Mating serrations hold
the sensor in position in the mounting sleeve.
PAS Pressure Sensor
ThePAS pump is driven from the crankshaft pulley via a
polyvee drive belt. Turning the steering wheel onto full lock
will place a considerable extra load on the engine compared
to the straight ahead position. To avoid the possibility of the
engine stalling, or running too slowly at idle, aPAS load signal
is produced by a sensor connected to the high pressure side
of the steering hydraulic pump. The sensor is located on the
outlet union of the pump body and is connected to the engine
management harness using connector EM009.
A/C Compressor Clutch Relay
The A/C clutch relay is located in relay position 7 in the engine
compartment fuse box and is a four pin relay using the DIN
pin layout. It does not contain any reverse polarity protection
devices.
The relay is controlled by theECM and, when energised,
supplies battery voltage to the A/C compressor clutch circuit
under the following conditions:
• A/C request from A/C system
• Engine speed above 500 rpm
• Refrigerant pressure within tolerance required by the
pressure switch
• Evaporator temperature above -7 °C (19 °F)
• Throttle angle less than 85°
• Engine temperature below 118 °C (244 °F)
Engine
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