Function

Function

Controlling the climate in the passenger compartment







The way in which the climate in the passenger compartment is regulated depends on the type of climate control module (CCM) in the car.

Electronic climate control
Electronic climate control means that either manual settings or the AUTO function can be used. In the latter case the control module automatically regulates heat, air conditioning, recirculation and air distribution until the selected temperature is achieved.

Manual climate control
Manual climate control means that heat, air conditioning, recirculation and air distribution must be selected manually.

STD
STD means that heat, recirculation and air distribution must be selected manually.

The climate control module (CCM) (3/112) regulates the following:
- Activation of the air conditioning (A/C) compressor (8/3) with a request via the Controller area network (CAN) to the engine control module (ECM) (4/46)
- Controlling the damper motors. For electronic climate control (6/48), (6/95), (6/96), (6/102) and (6/103). For manual climate control; (6/48), (6/69), (6/95) and (6/96)
- Blower fan speed (6/28).

The climate control module (CCM) regulates the climate in the passenger compartment based on the following input signals:
- The passenger compartment temperature, signal from the internal passenger compartment temperature sensor
- The outside temperature, signal from the outside temperature sensor (7/11)
- The evaporator temperature, signal from the evaporator temperature sensor (7/41)
- Sun roof status. Signal from the sun roof control module (4/33) via the upper electronic module (UEM) (4/70) over the Controller area network (CAN)
- Side window status. Signals from the driver door module (DDM) (3/126) and passenger door module (PDM) (3/127) via the Controller area network (CAN)
- Door status. Signal from the central electronic module (CEM) (4/56) via the Controller area network (CAN)
- Sun intensity. Signal from the sun sensor (7/12)
- Speed. Signal from the brake control module (BCM) (4/16) (previously ABS), via the Controller area network (CAN)
- Windshield wiper status. Signal from the steering wheel module (SWM) (3/130) via the Controller area network (CAN).

The climate control module (CCM) (for electronic climate control) uses information about the status of the sun roof, side windows and doors to determine how it should compensate for changes in the passenger compartment temperature. If side windows, doors or the sun roof are opened, the climate control module (CCM) will not compensate for a change in passenger compartment temperature. Instead it maintains the same level of climate control for the compressor and blower fan as before.

The climate control module (CCM) (for electronic climate control) uses the signal from the steering wheel module (SWM) to establish whether the windshield wipers are switched on. This is to regulate the blower fan and the damper motor to remove any mist from the inside of the windshield when it rains.

The climate control module (CCM) (for electronic climate control) uses the signal from the sun sensor to compensate for high sun intensity by decreasing the temperature of ventilation air, changing air distribution and increasing the speed of the blower fan.

The climate control module (CCM) (for electronic climate control and manual climate control) uses the signal from the evaporator temperature sensor to control the activation of the air conditioning (A/C) compressor. If the signal from the evaporator temperature sensor indicates an evaporator temperature below 6 degree C, the compressor cannot be activated because of the risk of freezing.

To maintain a constant flow of air in the passenger compartment the climate control module (CCM) (for electronic climate control) uses the speed signal from the brake control module (BCM) to regulate the speed of the blower fan. Generally, as the speed of the car increases the speed of the blower fan decreases.

At higher speeds the flow of air into the fresh air damper is adjusted.

Seat heaters







The seat heaters are activated by pressing the switches on the climate control module (CCM) (3/112). The climate control module (CCM) transmits information via the Controller area network (CAN) about the status selected for each seat to the central electronic module (CEM) (4/56). The central electronic module (CEM) then transmits the information to the relevant control module for seat heating (4/201, 4/202). The control modules for the seat heaters then control the current to the heater pad for the left-hand seat (9/16, 9/18) and right-hand seat (9/17, 9/19).

The central electronic module (CEM) also transmits information to the climate control module (CCM) about whether the seat heaters are activated or not. The climate control module (CCM) uses this information to light/turn off the LEDs on the buttons.

Recirculation control (electronic climate control only)







The climate control module (CCM) (3/112) controls the recirculation during the following conditions for electronic climate control:
- The recirculation switch is on (the LED lights orange)
- The system is in AUTO position and there is a large difference between the desired and current temperature
- The car is equipped with an air quality sensor, and the recirculation switch is on (the LED light green).

The air quality sensor transmits a signal to the climate control module (CCM) if it detects high concentrations of pollutants in the outside air. When this occurs the climate control module (CCM) transmits a signal to the damper motor for recirculation (6/48) to close the fresh air damper and to use recirculated air. The level of recirculation is controlled by the signal from the air quality sensor:
- signal 1 provides partial recirculation for speeds below 85 km/h, no recirculation for speeds exceeding 85 km/h
- signals 2 and 3 provide 100% recirculation.

If the high level of pollutants remains the system stays in recirculation for a certain time, maximum of 10 minutes. The time that the system is recirculating is determined by the outside temperature, if the air conditioning (A/C) is on and if the windshield wipers are activated. The system returns to fresh air for a short time before recirculation is resumed. The particle filter absorbs most of the pollutants entering the passenger compartment during this time. The maximum time prevents misting and musty air.

The air quality transmits information about the content of pollutants to the climate control module (CCM). This information is graded into four levels, and the information used for diagnosis.

Recirculation is never permitted if the defroster is selected. The climate control module (CCM) requests the compressor when the evaporator temperature exceeds 3 degree C.

Heated rear windshield and door mirrors







The heated rear windshield and door mirrors are activated by pressing the switch on the climate control module (CCM) (3/112). The climate control module (CCM) transmits information to the central electronic module (CEM) (4/56) about the selected heating status. The central electronic module (CEM) transmits a signal to the driver's door module (3/126) and passenger door module (PDM) (3/127) for the heated door mirrors and to the rear electronic module (REM) (4/58) for the heated rear windshield.

The central electronic module (CEM) also transmits information to the climate control module (CCM) about whether the seat heaters are activated or not. The climate control module (CCM) uses this information to light/turn off the LED on the button.

Switch functions, dashboard environment panel, (lower section)
The following functions can be activated using the switches on the dashboard environment panel:
- Folding head restraint, rear seat
- Folding door mirrors (market dependent)
- Bi-fuel, on/off (market dependent)
- Valet lock, on/off
- Child lock, on/off (market dependent)
- STC, off/on (option)
- DSTC, off/on (option)
- Auxiliary lamps, off/on (option)
- Reduced alarm, on/off (option).

In order for certain functions to be activated the engine must be switched on and/or the master key must be in position II.

Folding head restraints, rear seat
When the switch for the folding head restraints is activated, information is transmitted by the climate control module (CCM) (3/112) to the rear electrical module (4/58) via the Controller area network (CAN).

Folding door mirrors
When the switch for the folding door mirrors is activated, information is transmitted by the climate control module (CCM) to the driver's door module (3/126) and the passenger door module (PDM) (3/127) via the Controller area network (CAN).

Bi-fuel
When the bi-fuel switch is activated, a signal is transmitted from the climate control module (CCM) to the engine control module (ECM) (4/46) on the Controller area network (CAN) via the central electronic module (CEM). The engine control module (ECM) transmits a signal to the climate control module (CCM) about the type of fuel being used. The climate control module (CCM) uses this signal to light/turn off the LED on the switch.

HINT: This section will first be accessible during 2003.

Valet lock/child-proof lock
When activating the valet lock switch or the child lock switch information is transmitted to the rear electronic module (REM) via the Controller area network (CAN).

STC or DSTC
When the STC or DSTC switch is activated, a signal is transmitted from the climate control module (CCM) to the brake control module (BCM) (previously ABS) (4/16) via the Controller area network (CAN). The brake control module (BCM) transmits a signal to the climate control module (CCM) about whether the STC or DSTC functions are operating. The climate control module (CCM) uses this signal to light/turn off the LED on the switch.

Auxiliary lamps
When the auxiliary lamps switch is activated, information is transmitted from the climate control module (CCM) to the central electronic module (CEM). The central electronic module (CEM) transmits a signal to the climate control module (CCM) about whether the auxiliary lamps are on or not. The climate control module (CCM) uses this information to light/turn off the LED on the switch

Reduced alarm
When activating the reduced alarm switch information is transmitted via the Controller area network (CAN) to the upper electronic module (UEM) and rear electronic module (REM).

Rear A/C
When activating the switch for rear A/C information is transmitted via the Controller area network (CAN) to the rear electronic module (REM). From this signal and the signal from the engine control module (ECM) indicating whether the engine is running or not, the rear electronic module (REM) will activate/deactivate the relay supply to the rear A/C system. The rear electronic module (REM) transmits a signal indicating whether the rear A/C is on or not to the climate control module (CCM) via the control area network (CAN). The climate control module (CCM) uses this information to light/turn off the LED in the switch.

Diagnostic functions

General
The climate control module has a built-in diagnostic system which continuously monitors internal functions and input and output signals.

Diagnostic trouble codes (DTCs)
Diagnostic trouble codes (DTCs) are stored in the control module if the climate control module detects a fault. Every diagnostic trouble code (DTC) has a counter which records the number of cycles which have been fault-free since the diagnostic trouble code (DTC) was stored (intermittent fault). A fault which is detected in each operating cycle is defined as permanent. A fault which is detected in one or more (but not all) operating cycles is defined as intermittent.

An operating cycle is the period from when the ignition was switched on, remained on for at least 10 seconds and was finally switched off for at least 10 seconds.

Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function.

Reading off input and output signals
Using this function, the status or value of parameters can be read off. The presentation of the status or value can be obtained graphically or digitally.

Reading off extended fault-tracing information, climate control module
This function can be used to read parameters, status identifiers and counters stored at the same time as a diagnostic trouble code (DTC). These are called frozen values.

Description of programmable parameters, customer
Adaptation
Certain parameters of the climate control module can be read off and programmed using this function. The purpose of this programming is:
- to read the programmed parameters before replacing the control module. This is so the same parameters can be entered into the new control module
- to adapt the function of the control module for the equipment levels of the car (passenger compartment ventilation filter, parking heater)
- to adapt the function of the control module to the requirements of the driver.

Passenger compartment ventilation filter compensation, status
Indicates the status for the activation of passenger compartment ventilation filter compensation.

OFF = Compensation not active
ON = Compensation active (preset)

Blower fan run-on, status
Provides the status for activation of the blower fan run-on. The run-on dries the evaporator and prevents bad odors which may otherwise result from residual moisture in the system.

OFF = Run-on inactive
ON = Run-on active (preset)

Blower fan speed, value
Allows the speed to be modified for the blower fan when the climate control system is in AUTO position. Modifying the parameters means that the climate control system either blows more or less air than the preprogrammed value, to correspond to the request of the driver.

Gives the voltage value for adaptation of the blower fan speed.

-1.0 - +1.0 V (0 V preset)

Setting for air distribution for the floor/defroster residual heat, value
Indicates the setting of the air distribution between the floor and defroster.

10/90 - 90/10% (70/30% preset)

Setting for air distribution for the floor/defroster parking heater, value
Indicates the setting of the air distribution between the floor and defroster.

10/90 - 90/10% (70/30% preset)

Description of component/function activation

Self-adjustment of damper motors
This function can be used to carry out self adjustment of the limit positions for the damper motors. Self adjustment must be carried out if, after checks, one or more of the damper motors do not reach their limit positions or the climate control module is replaced. There are a number of possible reasons for a damper motor not reaching its end positions. For example, the motor or the damper has been turned manually, the voltage supply may have been cut, or a component has been replaced.

Downloading software and replacing the control module
New software can be downloaded into the climate control module. When ordering software, the hardware and the software in the car is compared to the Volvo central database. If the comparison is OK the software is downloaded to the control module.

If the comparison between the car and Volvo central database is not OK, the database is updated with the car configuration. When this is complete the software is downloaded.

The entire climate control module must be replaced as one unit. The exceptions are the fan for the passenger compartment temperature sensor and the switches on the lower section of the dashboard environment panel.

Five customer parameters can be programmed into the climate control module. These customer parameters are stored in the control module but not in the Volvo central database. This means that the customer parameters must be reprogrammed when the hardware is replaced.