
3.6
Climate Control Systems
3.6.1
Automatic Temperature Control (ATC)
The body control module (BCM) provides automatic temperature control support both through PCI
bus communications and through processing inputs to determine control for actuators and the
blower motor. The BCM interfaces with the ATC control head over the PCI bus. Information on
button activation, blower setting, and temperature setting are supplied to the BCM. In turn, the
BCM supplies the ATC control head with mode information and indication lamp status. The BCM
controls blower motor speed by providing a varying duty cycle of a fixed frequency output (pulse
width modulation). There are 14 distinct blower speeds, plus a blower off signal. The body control
module also controls the HVAC mode, temperature (blend air), and recirculation doors. This
system is either fully automatic or fully manual control (no semi-automatic functions); however, the
temperature blend door control is always automatically controlled based on sensor reading and
comfort setting. The in-car sensor and the aspirator motor are now housed in the ATC control
head.
3.6.2
Manual Temperature Control
The body control module interfaces with the a/c-heater control head via hardwired circuits.
Information for the temperature setting is supplied to the body control module via a potentiometer.
The rear defogger switch, A/C switch and the mode setting is supplied via a resistive multiplexed
circuit. The system on/off status is supplied by a dedicated circuit. The BCM drives the A/C and
rear defogger indicator lamps via hardwire to the A/C-heater control head.
3.6.3
HVAC Blend, Mode, and Recirculation Door Operation
The trouble codes that indicate a stall failure or a feedback signal failure work together to show
what is wrong with the HVAC system. The stall trouble codes mean that the body control module
cannot force an actuator to the end of the HVAC unit door. Internal problems in the body control
module will set other short- related codes. Having only stall trouble codes indicates that there is
a problem with an open or short circuit in the wiring, a bad actuator, a bad HVAC unit door or
connecting linkage. It is important that the operation of the HVAC door be checked if an actuator
is removed. This can be checked by rotating each unit door shaft to confirm that the door will stop
at both ends of travel. The actuator itself has no stops. It must have the HVAC unit door to stop
travel to pass a stall test.
A feedback signal failure can occur on the blend or mode door. The body control module monitors
the feedback signal to check the position of the actuator. The body control module not only checks
the level of the signal but also how much the voltage changes.
A feedback failure can occur if there is a short or open circuit in the wiring, a bad actuator, a bad
body control module, a bad HVAC unit door or connecting linkage. The easiest way to diagnose
this is to use the DRB to actuate the blend or mode door. Note that the feedback voltage of the
actuator should smoothly change as the actuator is moved. A sudden change in the feedback
voltage to a 5.0-volt or a 0.0-volt level indicates the actuator is bad. A fixed feedback voltage that
is less than 5.0 volts or greater than 0.0 volts without a stall failure, or a short failure indicates that
the actuator, the HVAC unit door, or a connecting mechanical linkage is jammed thereby
preventing movement. A feedback signal voltage that stays on 5.0 volts or 0.0 volts indicates a
wiring or body control module problem. The feedback voltage should always be less than 5.0 volts
and greater than 0.0 volts.
The feedback trouble code can also occur from lack of actuator travel. This can be checked by
confirming that the feedback signal smoothly changes when the actuator is moved with the DRB.
If the signal is OK, the door travel is not correct. The actuator must be removed and the HVAC unit
door mechanically checked for proper operation. Typical problems that prevent door movement
include screws dropped in the HVAC unit or warped doors. Replace any part that is found
defective.
G
E
N
E
R
A
L
I
N
F
O
R
M
A
T
I
O
N
8
Содержание 300M 1999
Страница 30: ...NOTES G E N E R A L I N F O R M A T I O N 20 ...
Страница 32: ...4 3 Fuse Block Junction Block 4 4 Airbag System G E N E R A L I N F O R M A T I O N 22 ...
Страница 33: ...4 5 Audio System G E N E R A L I N F O R M A T I O N 23 ...
Страница 34: ...4 5 Audio System continued G E N E R A L I N F O R M A T I O N 24 ...
Страница 35: ...4 6 Body Control Module and Junction Block G E N E R A L I N F O R M A T I O N 25 ...
Страница 37: ...4 7 2 Manual Temp Control G E N E R A L I N F O R M A T I O N 27 ...
Страница 38: ...4 7 2 Manual Temp Control continued 4 7 3 ATC and MTC G E N E R A L I N F O R M A T I O N 28 ...
Страница 39: ...4 8 Chime 4 9 Door Ajar G E N E R A L I N F O R M A T I O N 29 ...
Страница 40: ...4 9 Door Ajar continued 4 10 Exterior Interior Lighting G E N E R A L I N F O R M A T I O N 30 ...
Страница 41: ...G E N E R A L I N F O R M A T I O N 31 ...
Страница 42: ...4 11 Instrument Cluster FUEL TANK SENDING UNIT G E N E R A L I N F O R M A T I O N 32 ...
Страница 43: ...4 12 Memory System G E N E R A L I N F O R M A T I O N 33 ...
Страница 44: ...4 12 Memory System continued G E N E R A L I N F O R M A T I O N 34 ...
Страница 45: ...4 13 OTIS G E N E R A L I N F O R M A T I O N 35 ...
Страница 46: ...4 13 OTIS continued 4 14 Power Door Locks RKE G E N E R A L I N F O R M A T I O N 36 ...
Страница 47: ...G E N E R A L I N F O R M A T I O N 37 ...
Страница 48: ...4 15 Sentry Key Immobilizer System 4 16 Vehicle Communication System G E N E R A L I N F O R M A T I O N 38 ...
Страница 49: ...ABS PCM TCM G E N E R A L I N F O R M A T I O N 39 ...
Страница 50: ...4 17 Vehicle Theft Security System G E N E R A L I N F O R M A T I O N 40 ...
Страница 51: ...4 18 Wiper System G E N E R A L I N F O R M A T I O N 41 ...
Страница 52: ...4 18 Wiper System continued G E N E R A L I N F O R M A T I O N 42 ...
Страница 55: ...6 0 FIELD EXPERIENCE NOTES G E N E R A L I N F O R M A T I O N 45 ...
Страница 56: ...NOTES G E N E R A L I N F O R M A T I O N 46 ...
Страница 57: ...7 0 DIAGNOSTIC INFORMATION AND PROCEDURES 7 1 GENERAL TROUBLESHOOTING 47 ...
Страница 62: ...TEST 2A REPAIRING CLUSTER MESSAGE MISMATCH Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 52 ...
Страница 66: ...TEST 3A CONTINUED REPAIRING DRIVER SQUIB CIRCUIT OPEN FIG 1 FIG 2 A I R B A G S Y S T E M 56 ...
Страница 76: ...TEST 7A CONTINUED REPAIRING LOSS OF IGNITION RUN ONLY FIG 1 FIG 2 FIG 3 A I R B A G S Y S T E M 66 ...
Страница 80: ...TEST 8A CONTINUED REPAIRING LOSS OF IGNITION RUN START FIG 1 FIG 2 FIG 3 A I R B A G S Y S T E M 70 ...
Страница 84: ...TEST 10A REPAIRING NO CLUSTER IFR MESSAGE Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 74 ...
Страница 86: ...TEST 11A REPAIRING NO PCI COMMUNICATION Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 76 ...
Страница 96: ...TEST 16A REPAIRING POWER STAGE NOT TESTED Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 86 ...
Страница 98: ...TEST 17A REPAIRING WARNING LAMP OPEN SHORTED Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 88 ...
Страница 100: ...TEST 18A REPAIRING STORED TROUBLE CODES Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 90 ...
Страница 102: ...TEST 19A AIRBAG CONTROL MODULE REPLACEMENT PROCEDURE Perform TEST 1A Before Proceeding A I R B A G S Y S T E M 92 ...
Страница 108: ...TEST 1C REPAIRING SHORTED FRONT CHANNEL Perform TEST 1A Before Proceeding FIG 1 FIG 2 A U D I O S Y S T E M S 98 ...
Страница 110: ...TEST 1C CONTINUED REPAIRING SHORTED FRONT CHANNEL FIG 1 FIG 2 A U D I O S Y S T E M S 100 ...
Страница 112: ...TEST 1D REPAIRING SHORTED REAR CHANNEL Perform TEST 1A Before Proceeding FIG 1 A U D I O S Y S T E M S 102 ...
Страница 114: ...TEST 1D CONTINUED REPAIRING SHORTED REAR CHANNEL FIG 1 A U D I O S Y S T E M S 104 ...
Страница 116: ...TEST 1E REPAIRING SHORTED LEFT CHANNEL Perform TEST 1A Before Proceeding FIG 1 FIG 2 A U D I O S Y S T E M S 106 ...
Страница 118: ...TEST 1E CONTINUED REPAIRING SHORTED LEFT CHANNEL FIG 1 FIG 2 A U D I O S Y S T E M S 108 ...
Страница 120: ...TEST 1F REPAIRING SHORTED RIGHT CHANNEL Perform TEST 1A Before Proceeding FIG 1 FIG 2 A U D I O S Y S T E M S 110 ...
Страница 122: ...TEST 1F CONTINUED REPAIRING SHORTED RIGHT CHANNEL FIG 1 FIG 2 A U D I O S Y S T E M S 112 ...
Страница 222: ...TEST 2A REPAIRING CHIME INOPERATIVE AT ALL TIMES Perform TEST 1A Before Proceeding C H I M E S Y S T E M 212 ...
Страница 224: ...TEST 3A REPAIRING CHIME INOPERATIVE WITH EXTERIOR LAMPS ON Perform TEST 1A Before Proceeding C H I M E S Y S T E M 214 ...
Страница 230: ...TEST 6A REPAIRING CHIME BEEP REQUEST INOPERATIVE Perform TEST 1A Before Proceeding C H I M E S Y S T E M 220 ...
Страница 236: ...TEST 9A REPAIRING CHIME SOUNDS WITH DRIVER DOOR OPEN Perform TEST 1A Before Proceeding FIG 1 C H I M E S Y S T E M 226 ...
Страница 260: ...TEST 2A CONTINUED REPAIRING HEADLAMP SWITCH INPUT FAILURE FIG 1 FIG 2 E X T E R I O R L I G H T I N G S Y S T E M 250 ...
Страница 274: ...TEST 4A CONTINUED REPAIRING LOW BEAM HEADLAMPS THAT WILL NOT TURN OFF E X T E R I O R L I G H T I N G S Y S T E M 264 ...
Страница 298: ...TEST 9A CONTINUED REPAIRING FOG LAMPS THAT WILL NOT TURN ON FIG 1 E X T E R I O R L I G H T I N G S Y S T E M 288 ...
Страница 308: ...TEST 2A CONTINUED REPAIRING FUEL LEVEL SENDING UNIT FAILURE I N S T R U M E N T C L U S T E R 298 ...
Страница 312: ...TEST 3A CONTINUED REPAIRING DIMMING LEVEL SWITCH FAILURE FIG 1 I N S T R U M E N T C L U S T E R 302 ...
Страница 316: ...TEST 5A IDENTIFYING THE INOPERATIVE GAUGE Perform TEST 1A Before Proceeding FIG 1 I N S T R U M E N T C L U S T E R 306 ...
Страница 318: ...TEST 5A CONTINUED IDENTIFYING THE INOPERATIVE GAUGE NOTES I N S T R U M E N T C L U S T E R 308 ...
Страница 322: ...TEST 7A IDENTIFYING WARNING LAMP PROBLEMS Perform TEST 1A Before Proceeding NOTES I N S T R U M E N T C L U S T E R 312 ...
Страница 326: ...TEST 8A REPAIRING PRND3L INDICATOR MALFUNCTIONS Perform TEST 1A Before Proceeding I N S T R U M E N T C L U S T E R 316 ...
Страница 332: ...TEST 9B CONTINUED REPAIRING PANEL ILLUMINATION SHORTED TO BATTERY FIG 1 I N S T R U M E N T C L U S T E R 322 ...
Страница 336: ...TEST 9C CONTINUED REPAIRING PANEL ILLUMINATION SHORTED TO GROUND FIG 1 I N S T R U M E N T C L U S T E R 326 ...
Страница 338: ...TEST 10A REPAIRING FAULTY GAUGE Perform TEST 5A Before Proceeding NOTES I N S T R U M E N T C L U S T E R 328 ...
Страница 344: ...TEST 12A CONTINUED REPAIRING FUEL GAUGE LED OPERATION I N S T R U M E N T C L U S T E R 334 ...
Страница 350: ...TEST 13A REPAIRING SPEEDOMETER OPERATION Perform TEST 5A Before Proceeding NOTES I N S T R U M E N T C L U S T E R 340 ...
Страница 356: ...TEST 15A CONTINUED REPAIRING OIL PRESSURE WARNING LAMP OPERATING IMPROPERLY FIG 1 I N S T R U M E N T C L U S T E R 346 ...
Страница 360: ...TEST 16A REPAIRING SEAT BELT LED Perform TEST 1A Before Proceeding NOTES I N S T R U M E N T C L U S T E R 350 ...
Страница 374: ...TEST 19A REPAIRING DOOR AJAR INDICATOR Perform TEST 1A Before Proceeding I N S T R U M E N T C L U S T E R 364 ...
Страница 376: ...TEST 19A CONTINUED REPAIRING DOOR AJAR INDICATOR NOTES I N S T R U M E N T C L U S T E R 366 ...
Страница 380: ...TEST 20A CONTINUED REPAIRING TRUNK AJAR INDICATOR FIG 1 I N S T R U M E N T C L U S T E R 370 ...
Страница 398: ...TEST 5A CONTINUED REPAIRING COURTESY LAMPS ON AT ALL TIMES FIG 1 I N T E R I O R L I G H T I N G S Y S T E M 388 ...
Страница 488: ...TEST 21A CONTINUED REPAIRING LEFT SEAT HEAT OUTPUT OPEN TROUBLE CODE FIG 1 FIG 2 M E M O R Y S Y S T E M 478 ...
Страница 492: ...TEST 22A CONTINUED REPAIRING LEFT SEAT HEAT OUTPUT SHORTED TO GROUND TROUBLE CODE FIG 1 M E M O R Y S Y S T E M 482 ...
Страница 504: ...TEST 27A CONTINUED REPAIRING LEFT THERMISTOR OUT OF RANGE HIGH TROUBLE CODE FIG 1 M E M O R Y S Y S T E M 494 ...
Страница 508: ...TEST 28A CONTINUED REPAIRING RIGHT SEAT HEAT OUTPUT OPEN TROUBLE CODE FIG 1 FIG 2 M E M O R Y S Y S T E M 498 ...
Страница 512: ...TEST 29A CONTINUED REPAIRING RIGHT SEAT HEAT OUTPUT SHORTED TO GROUND TROUBLE CODE FIG 1 M E M O R Y S Y S T E M 502 ...
Страница 524: ...TEST 34A CONTINUED REPAIRING RIGHT THERMISTOR OUT OF RANGE HIGH TROUBLE CODE FIG 1 M E M O R Y S Y S T E M 514 ...
Страница 542: ...TEST 43A REPAIRING INOPERATIVE MEMORY SWITCH Perform TEST 1A Before Proceeding FIG 1 M E M O R Y S Y S T E M 532 ...
Страница 544: ...TEST 43A CONTINUED REPAIRING INOPERATIVE MEMORY SWITCH FIG 1 FIG 2 M E M O R Y S Y S T E M 534 ...
Страница 546: ...TEST 43B REPAIRING INOPERATIVE MEMORY SWITCH Perform TEST 43A Before Proceeding FIG 1 FIG 2 M E M O R Y S Y S T E M 536 ...
Страница 548: ...TEST 43C REPAIRING INOPERATIVE MEMORY SWITCH Perform TEST 43A Before Proceeding FIG 1 FIG 2 M E M O R Y S Y S T E M 538 ...
Страница 634: ...TEST 2A CONTINUED REPAIRING AIRBAG CONTROL MODULE NO RESPONSE FIG 1 FIG 2 V E H I C L E C O M M U N I C A T I O N 624 ...
Страница 644: ...TEST 4A CONTINUED REPAIRING BODY CONTROL MODULE NO RESPONSE FIG 1 FIG 2 V E H I C L E C O M M U N I C A T I O N 634 ...
Страница 646: ...TEST 4A CONTINUED REPAIRING BODY CONTROL MODULE NO RESPONSE FIG 1 V E H I C L E C O M M U N I C A T I O N 636 ...
Страница 662: ...TEST 9A CONTINUED REPAIRING RADIO NO RESPONSE CONDITION FIG 1 V E H I C L E C O M M U N I C A T I O N 652 ...
Страница 672: ...TEST 12A CONTINUED REPAIRING PCI BUS CIRCUIT SHORTED TO BATTERY V E H I C L E C O M M U N I C A T I O N 662 ...
Страница 678: ...TEST 13A CONTINUED REPAIRING PCI BUS CIRCUT SHORTED TO GROUND V E H I C L E C O M M U N I C A T I O N 668 ...
Страница 688: ...TEST 2A DISARMING THE SYSTEM Perform TEST 1A Before Proceeding V E H I C L E T H E F T S E C U R I T Y S Y S T E M 678 ...
Страница 692: ...TEST 3A CONTINUED REPAIRING VTSS INDICATOR LAMP STAYS ON FIG 1 V E H I C L E T H E F T S E C U R I T Y S Y S T E M 682 ...
Страница 710: ...TEST 5A CONTINUED REPAIRING WIPERS NOT WORKING AT ALL FIG 1 W I N D S H I E L D W I P E R S Y S T E M 700 ...
Страница 714: ...TEST 5B CONTINUED REPAIRING WIPERS NOT WORKING AT ALL FIG 1 W I N D S H I E L D W I P E R S Y S T E M 704 ...
Страница 748: ...TEST VER 4A VERIFICATION TEST MEMORY SYSTEM NOTES V E R I F I C A T I O N T E S T 738 ...
Страница 751: ...10 0 SCHEMATIC DIAGRAMS 10 1 Airbag System G E N E R A L I N F O R M A T I O N 741 ...
Страница 752: ...10 2 Body Control Module G E N E R A L I N F O R M A T I O N 742 ...
Страница 753: ...10 3 Audio Systems Midline Premium G E N E R A L I N F O R M A T I O N 743 ...
Страница 754: ...10 3 Audio Systems Premium 2 10 4 Chime Warning System G E N E R A L I N F O R M A T I O N 744 ...
Страница 755: ...10 5 Climate Control Automatic Temperature Control G E N E R A L I N F O R M A T I O N 745 ...
Страница 756: ...10 5 Climate Control Manual Temperature Control 10 6 Door Ajar G E N E R A L I N F O R M A T I O N 746 ...
Страница 757: ...10 7 Exterior Lighting G E N E R A L I N F O R M A T I O N 747 ...
Страница 758: ...10 8 Instrument Cluster 10 9 Interior Lighting G E N E R A L I N F O R M A T I O N 748 ...
Страница 759: ...10 9 Interior Lighting G E N E R A L I N F O R M A T I O N 749 ...
Страница 760: ...10 10 Memory System G E N E R A L I N F O R M A T I O N 750 ...
Страница 761: ...10 11 OTIS G E N E R A L I N F O R M A T I O N 751 ...
Страница 762: ...10 12 Power Door Locks RKE G E N E R A L I N F O R M A T I O N 752 ...
Страница 763: ...10 13 Vehicle Communications 10 14 Vehicle Theft Security System G E N E R A L I N F O R M A T I O N 753 ...
Страница 764: ...10 15 Wiper System G E N E R A L I N F O R M A T I O N 754 ...
Страница 766: ...756 ...