A/c-Heater System: Overview Saab 9-5 I

DESCRIPTION

Under normal conditions the Automatic Climate Control (ACC) system maintains selected temperature inside vehicle regardless of ambient (outside) temperature. There are separate temperature controls for driver and passengers that allow driver to select temperatures 9°F (5°C) warmer or cooler than passengers. ACC panel (control unit) monitors and controls air distribution, blower motor speed, air recirculation, and selected temperatures based on inputs from 5 different sensors.

ACC system sensors include an in-vehicle temperature sensor, ambient (outside) temperature sensor, left and right outlet air temperature sensors, and a sunload sensor. ACC system consists of 5 sensors, ACC control panel, 2 mixed-air stepping motors, air distribution flap stepping motor, air recirculation direct current motor, variable speed direct current blower motor, blower motor speed control module, heater core coolant shutoff solenoid valve, coolant circulation pump, and rear door fans.

DELAYED BLOWER MOTOR OPERATION

Note. When engine is started, blower motor and heated rear window should be active within 5 seconds. Activation occurs when DICE control module has received IGNITION +54 ON and IGNITION +15 ON signals. If activation is delayed 20 seconds after engine has been started, DICE control module has not received an IGNITION +54 ON signal.

1. Ensure ACC control module has not been reprogrammed by user to delay blower motor and electrically heated rear window activation. See «ACC CONTROL MODULE PROGRAMMING»(ref-353-S07542479952000030800000) under PROGRAMMING. If ACC control module has not been programmed, go to next step. If ACC control module has been programmed, clear programming and go to step 6.
2. Turn ignition off. Connect scan tool to Data Link Connector (DLC), located under steering column. If scan tool is not available, go to step 4. Turn ignition on. Using scan tool, contact DICE control module. Check value for IGNITION +54 signal. If value is ON, go to next step. If value is not ON, repair open in Violet wire between fuse "C" (7.5-amp) and DICE 70-pin connector terminal No. 31. (Scheme 1) See «WIRING DIAGRAMS»(ref-353-S11026198212000030800000). DICE control module is located under driver's side of instrument panel. When repair is completed, go to step 6.
3. Turn ignition off. Using scan tool, check value for IGNITION +54 signal. If value is OFF, go to step 6. If value is not OFF, repair short to battery voltage in Violet wire between fuse "C" (7.5-amp) and DICE 70-pin connector terminal No. 31. When repair is completed, use scan tool to clear all DTCs in all systems and go to step 6.
4. Turn ignition off. Remove driver's side lower panel under steering column. Remove main fuse board cover located between instrument panel and driver's door. Disconnect DICE control module 70-pin connector. Check for voltage between 70-pin connector terminal No. 31 (Violet wire) and terminal No. 57 (Black wire). If voltage is not present, go to next step. If voltage is present, repair short to battery voltage in Violet wire between fuse "C" and DICE 70-pin connector.
5. Turn ignition on. Measure voltage between 70-pin connector terminal No. 31 (Violet wire) and terminal No. 57 (Black wire). If battery voltage is present, go to next step. If battery voltage is not present, repair open in Violet wire between fuse "C" and DICE 70-pin connector. Ensure problem is corrected.
6. Using scan tool, clear all DTCs from all systems. Recheck A/C system operation for original complaint. If A/C system is operating properly and no DTC has been detected, repair is complete. If A/C system is not operating properly and/or a DTC has been detected, DICE control module may need to be replaced. See «CONTROL MODULES»(ref-353-S38072570922000030800000) under TESTING.

Scheme 1

NO A/C OPERATION

Note. No A/C operation is concerned with conditions pertaining to A/C system being on. If A/C compressor clutch engages, go to NO OR INSUFFICIENT COOLING .

1. Turn ignition off. Connect scan tool to Data Link Connector (DLC), located under steering column. Turn ignition on. Using scan tool, contact DICE control module and ensure DICE is programmed for A/C. If DICE control module is programmed for A/C, go to next step. If DICE control module is not programmed for A/C, program DICE for A/C using scan tool. Clear DTCs from all systems. Ensure A/C system is operating properly. If A/C system is operating properly, repair is complete. If A/C system is not operating properly, replace DICE control module. See «CONTROL MODULES»(ref-353-S38072570922000030800000) under TESTING.
2. Check ambient (outside) temperature displayed on Saab Information Display (SID). If temperature displayed is more than 41°F (5°C), go to next step. If temperature displayed is less than 41°F (5°C), go to step 4 .
3. Turn ignition on. Using scan tool, contact TRIONIC engine control module. Activate A/C RELAY (ON). A/C compressor clutch should engage. If clutch engages, go to step 5 . If clutch does not engage, go to step 12 .
4. Park vehicle in an area where ambient temperature is more than 41°F (5°C). Turn ignition on. Using scan tool, contact ACC control module. Activate OUTSIDE TEMPERATURE 20°C (ON) and A/C RELAY (ON). The A/C compressor clutch should engage. If clutch engages, go to next step. If clutch does not engage, go to step 12 .
5. Start engine and allow to idle. Using scan tool, contact DICE control module and read A/C IN (BUS FROM ACC). Scan tool should display ON. If scan tool displays ON, go to next step. If scan tool does not display ON, replace ACC control module. See «CONTROL MODULES»(ref-353-S38072570922000030800000) under TESTING.
6. With engine idling at normal operating temperature, read A/C PRESSURE using scan tool. If pressure displayed is less than 29 psi (2.0 kg/cm 2 ) or more than 392 psi (27.5 kg/cm 2 ), go to next step. If pressure displayed is 29-392 psi (2.0-27.5 kg/cm 2 ), go to step 8 .
7. Connect A/C system manifold gauge set to A/C refrigerant system. With engine idling at normal operating temperature, read A/C PRESSURE using scan tool. If value displayed on scan tool and value displayed on high-side pressure gauge agree, repair A/C refrigerant system leak. Evacuate and charge A/C system, and ensure proper A/C operation. If value displayed on scan tool and value displayed on high-side pressure gauge do not agree, replace A/C pressure sensor. See «A/C PRESSURE SENSOR»(ref-353-S22807640622000030800000) under REMOVAL & INSTALLATION.
8. With engine idling at normal operating temperature, contact DICE and read COOLANT TEMPERATURE (BUS FROM TRIONIC) using scan tool. If engine coolant temperature displayed is less than 257°F (125°C), go to next step. If engine coolant temperature displayed is more than 257°F (125°C), compare with actual coolant temperature. If compared temperatures seem reasonable, A/C has not been allowed to operate because of high engine temperature. If compared temperatures do not seem reasonable, perform repairs as necessary and ensure proper A/C operation.
9. With engine idling at normal operating temperature, contact DICE and read EVAPORATOR TEMPERATURE using scan tool. If evaporator temperature displayed is more than 41°F (5°C), go to next step. If evaporator temperature displayed is less than 41°F (5°C), compare with actual evaporator temperature. If compared temperatures seem reasonable, A/C has not been allowed to operate because of low evaporator temperature. If compared temperatures do not seem reasonable, perform repairs as necessary and ensure proper A/C system operation.
10. With engine idling at normal operating temperature, contact TRIONIC engine control module and read A/C IN using scan tool. Scan tool should display ON. If scan tool displays ON, replace engine control module. If scan tool does not display ON, replace DICE control module. See «CONTROL MODULES»(ref-353-S38072570922000030800000) under TESTING. After replacing suspect control module, go to next step.
11. Delete DTCs from all systems. Drive vehicle, varying engine loads and engine speeds for at least 5 minutes. Ensure proper A/C system operation and that no DTCs have been set. If system is not operating properly, see «CONTROL MODULES»(ref-353-S38072570922000030800000) under TESTING.
12. Turn ignition off. Disconnect A/C compressor clutch connector. Using a fused jumper wire, connect battery voltage to compressor clutch connector terminal (Yellow wire). See «WIRING DIAGRAMS»(ref-353-S11026198212000030800000) . If compressor clutch engages, go to next step. If compressor clutch does not engage, replace compressor clutch. Ensure gap between compressor clutch and drive pulley is 0.014-0.026" (0.35-0.65 mm).
13. Remove A/C compressor relay, located in engine compartment main fuse/relay box. Main fuse/relay box is located behind battery. Connect a test light between ground and relay connector terminal No. 1/30 (Red wire). If test light comes on, go to next step. If test light does not come on, repair Red wire between relay connector terminal No. 1 and fuse No. 14 (10-amp) located in main fuse/relay box.
14. Connect a fused jumper wire between A/C relay connector terminals No. 1/30 (Red wire) and No. 2/87 (Yellow wire). Connect a test light between ground and A/C compressor clutch harness connector terminal (Yellow wire). If test light comes on, replace A/C compressor relay. If test light does not come on, repair Yellow wire between A/C compressor relay and compressor clutch.