air conditioning RENAULT KANGOO 1997 KC / 1.G Engine And Peripherals User Guide

INJECTION
Injection/air conditioning programming
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THIS VEHICLE IS FITTED WITH A VARIABLE OUTPUT COMPRESSOR
AIR CONDITIONING/INJECTION COMPUTER CONNECTION
The electrical connection :
- between the air conditioning computer and the injection computer consists of a single wire (track 5).
This track carries two types of information :
-the fast idle speed request information . For this information to be transmitted to the injection
computer , two conditions must be fulfilled :
• the air conditioning function must have been selected on the control panel ,
• the pressure in the air conditioning circuit must be greater than a certain threshold.
If this information is transmitted, the fast idle speed is obtained (it is therefore normal that
sometimes, when the air conditioning is switched on, engine idling, there is no fast idle speed ).
-the Absorbed Power information. This information has no influence on the idle speed. It simply
informs the injection computer of the torque value taken up by the compressor; the computer, in
turn, acts on the idle speed regulation solenoid. The absorbed power may be visualised using the
XR25. When the air conditioning is switched on , #44 should be between 300 and 5 000 watts.
IMPORTANT: the value at #44 or idle speed is never equal to 0, whatever the status of the
compressor, off or on . The minimum value which may be read using #44 is approximately 300
watts.
- between the the injection computer and the air conditioning computer consists of a single wire (track
51). This track carries the information regarding the authorisation or prevention of compressor
operation.
COMPRESSOR OPERATION PROGRAMMING
During certain operating phases, the injection computer prevents the compressor from operating.
Programming when starting engine
The compressor is prevented from functioning for 10 seconds after starting the engine .
Recovery of performance ( D7F engine)
Depending on the torque required by the driver and on the power absorbed by the air conditioning
compressor, the injection computer stops or allows the operation of the compressor .
Anti-stalling function (D7F engine)
If the no load position is recognised , and the engine speed is lower than 600 rpm, and if the power absorbed
by the compressor is greater than 300 watts, the compressor disengages .
It engages again if:
- the no load position is recognised when the engine speed reaches 850 rpm.,
- if the no load position is not recognised when the engine speed reaches 1 800 rpm.
Thermal protection programming ( E7J engine )
The compressor does not engage in cases where the coolant temperature is greater than or equal to +
115°C.
Over-revving protection (E7J engine )
The compressor is prevented from operating if the engine speed is greater than 5 900 rpm.
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INJECTION
Idle speed correction
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CONNECTION BETWEEN THE POWER ASSISTED STEERING PRESSOSTAT AND THE INJECTION COMPUTER
The injection computer receives information from the power assisted steering pressostat . This varies
depending on the pressure present in the hydraulic circuit. The higher the pressure, , the more energy is
absorbed by the power assisted steering pump.
To compensate for this energy absorption, the injection computer increases the opening ratio of the idle
speed regulation stepping motor.
The information is received on track 13 of the injection computer. If the pressostat is closed , the computer
receives an earth . The idle speed is adjusted to 800 rpm for the D7F engine and 850 rpm for the E7J
engine .
IDLE SPEED CORRECTION DEPENDING ON THE BATTERY VOLTAGE
The objective of this correction is to compensate for the drop in voltage, due to consumer operation when
the battery is poorly charged To correct this, the idle speed is increased, allowing the alternator to rotate
faster and consequently increase the charging voltage.
The lower the voltage, the greater the degree of correction. Correction of the engine speed is therefore
variable. It begins when the voltage drops to below 12.7 Volts. Correction begins at the nominal engine
speed and may reach a maximum of 880 rpm for the D7F engine and 930 rpm for the
E7J engine .
IDLE SPEED CORRECTION DEPENDING ON AIR CONDITIONING OPERATION
The injection computer increases the idle speed to 850 rpm. for the D7F engine and 880 rpm . for the E7J
engine , provided it receives the fast idle speed information from the air conditioning computer.
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