AUTOMATIC ZONE CONTROL SYSTEM The Automatic Zone Control (AZC) control module has a system self-diagnostic mode which continuously monitors various parameters during normal system operation. If a system fault is detected, a current and historical fault is recorded. When the current fault is cleared, the historical fault remains until reset (manually or automatically) Both the current and historical fault codes can be accessed through either the front panel, or over the Programmable Communications Interface (PCI) bus using a DRBIIIŽ scan tool, and the proper Diagnostic Procedures manual. The AZC control module is capable of three different types of self-diagnostic tests, as follows: Fault Code Tests Input Circuit Tests Output Circuit/Actuator Tests The information that follows describes: How to read the self-diagnostic display How to enter the AZC control module self-diagnostic test mode How to select the self-diagnostic test types How to perform the different tests ENTERING THE AZC SELF-DIAGNOSTIC MODE To enter the AZC self-diagnostic mode, perform the following: Depress the A/C and Recirc buttons at the same time and hold. Rotate the left temperature control knob clockwise (CW) one detent. If you continue to hold the A/C and Recirc buttons depressed, the AZC control module will perform a Segment Test of the vacuum fluorescent (VF) display. In the Segment Test you should see all of the display segments illuminate as long as both buttons are held. If a display segment fails to illuminate, the vacuum fluorescent display is faulty and the heater-A/C control must be replaced. After viewing the Segment Test, release the A/C and Recirc buttons and the display will clear momentarily. If a 0 is displayed, then no faults are set in the system. Should there be any faults, either "current" or "historical", all fault codes will be displayed in ascending numerical sequence (note no effort is made to display fault codes in chronological order) Each fault code is displayed for one second before the next code is displayed. Once all fault codes have been displayed, the system will then repeat the fault code numbers. This will continue until the left side set temperature control is moved at least one detent position in the CW direction or the ignition is turned "OFF". FAULT CODE TESTS Fault codes are two-digit numbers that identify a circuit that is malfunctioning. There are two different kinds of fault codes. Current Fault Codes - Current means the fault is present right now. There are two types of current faults: input faults, and system faults. Historical Fault Codes - Historical or stored means that the fault occurred previously, but is not present right now. A majority of historical fault codes are caused by intermittent wire harness or wire harness connector problems. CURRENT FAULT CODES Input faults 01 = IR thermister circuit open 02 = IR thermister circuit shorted 03 = Fan pot shorted 04 = Fan pot open 05 = Mode pot shorted 06 = Mode pot open 07 = IR sensor delta too large 08 = Reserved 09 = Reserved 10 = Reserved 11 = Engine air intake temperature Buss message missing 12 = Country code Buss message missing System Faults 13 = Mode motor not responding 14 = AI (Recirc) motor not responding 15 = Left temperature door not responding 16 = Right temperature door not responding 17 = Mode door travel range too small 18 = Mode door travel range too large 19 = AI (Recirc) door travel too small 20 = AI (Recirc) door travel too large 21 = Left temperature door travel too small 22 = Left temperature door travel too large 23 = Right temperature door travel too small 24 = Right temperature door travel too large 25 = Calibration check sum error 26 = Engine coolant temp bus message missing 27 = Vehicle speed bus message missing 28 = Engine RPM bus message missing 29 = OAT bus message missing 30 = Display intensity bus message missing 31 = VIN number bus message missing 32 = Reserved HISTORICAL FAULT CODES Input faults 33 = IR thermister circuit was open 34 = IR thermister circuit was shorted 35 = Fan pot was shorted 36 = Fan pot was open 37 = Mode pot was shorted 38 = Mode pot was open 39 = IR sensor delta was too large 40 = Reserved 41 = Reserved 42 = Reserved 43 = Engine air intake temperature Buss message missing 44 = Country code Buss message missing System Faults 45 = Mode motor was not responding 46 = AI (Recirc) motor was not responding 47 = Left temperature door was not responding 48 = Right temperature door was not responding 49 = Mode door travel range too small 50 = Mode door travel range too large 51 = AI (Recirc) door travel range too small 52 = AI (Recirc) door travel range too large 53 = Left temperature door travel too small 54 = Left temperature door travel too large 55 = Right temperature door travel too small 56 = Right temperature door travel too large 57 = Calibration check sum error 58 = Engine coolant temp bus message missing 59 = Vehicle speed bus message missing 60 = Engine RPM bus message missing 61 = OAT bus message missing 62 = Display intensity bus message missing 63 = VIN number bus message missing 64 = Reserved 65 = Reserved 66 = Reserved 67 = Reserved NOTE: A battery disconnect will erase all faults stored in Random Access Memory (RAM) of the AZC control module. It is recommended that all faults be recorded before they are erased. RETRIEVING FAULT CODES To begin the fault code tests, depress the A/C and Recirc buttons at the same time and rotate the left temperature control knob clockwise (CW) one detent, then release the push-button. If there are no fault codes, the "00" display value will remain in the VF window. Should there be any codes, each will be displayed for one second in ascending numerical sequence (note: no effort is made to display faults in the order they occurred) The left side set temperature display will be blanked and the right side set temperature display will indicate current and historical codes (8 historical max) presently active. Once all codes have been displayed, the system will repeat the fault code numbers. This will continue until the left side set temperature control is moved at least one detent position in either direction, by pressing both the A/C and Recirc buttons at the same time, or the ignition is turned off. Record all of the fault codes, then see the Current and Historical Fault Code charts for the descriptions. CLEARING FAULT CODES Current faults cannot be electronically cleared. Repair must be made to the system to eliminate the fault causing code. Historical fault codes can be cleared manually, or automatically. To clear a historical fault manually, depress and hold either the A/C or Recirc button for at least three seconds while the display is in the fault code mode of operation. Historical fault codes are cleared automatically when the corresponding current fault code has been cleared, and has remained cleared for a number of ignition cycles. The faults have been cleared when two horizontal bars appear in the Test Selector display. EXITING SELF-DIAGNOSTIC MODE The self-diagnostic mode can be exited by pressing both the A/C and Recirc buttons at the same time, or turning off the ignition. MONITOR CURRENT PARAMETERS While in the display fault code mode of operation, current system parameters can also be monitored and/or forced. Rotating the left side set temperature control clockwise will increase the pointer number while rotating the control counter clockwise will decrease the pointer number. Rotating the right set temperature control will have no impact on pointer value or the value of the parameter being monitored. Once the desired pointer number has been selected, pressing either the AC or Recirc buttons will display the current value of the selected parameter. The right side set temperature display is only capable of displaying only values ranging from 0 to 99, the left side set temperature display is used for values greater than 99. If the value is less than 99, the left side set temperature display remains blanked. While a parameter is being overridden, the system will continue to function normally except for the parameter which is being manually controlled. For values < 0, the "G" segment in the left side set temperature Most Significant Digit (MSD)(or left-most number in the pair) will be used to indicate a negative number. For values between -01 to -99 the Least Significant Digit (LSD)(or right-most number of the pair) in the left side set temperature will remain blank. System control of parameter being displayed can be overridden by rotating the right set temperature control in either direction. Rotating the right temperature control in the CW direction, the selected parameter value is overridden and incremented beginning at the value which was being displayed. Rotating the right temperature control in the CCW direction, the selected parameter value is overridden and decremented beginning at the value which was being displayed. The rate at which incrementing and decrement occurs is one unit value per set temperature detent position. HVAC SYSTEM POINTER Pointer Number DESCRIPTION Value Displayed 01 A/C Enable 0 or 1 0 = disabled 1 = enabled 02 Final fan PWM duty cycle 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 03 Left NPRG * 0 to 255 * NPRG equals a calculated number based on outside and in-vehicle conditions. This value is used by the AZC to position the Mode motor, Air Inlet motor, and control blower motor speed. - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 04 Right NPRG 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 05 Avg NPRG 0 TO 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 06 Primary control side 0 or 1 0 = left 1 = right 07 EE Check sum (calculated) 0 to 255 08 Target intensity (in % ON time) 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 09 Not Used 0 to 0 10 Not Used 0 to 0 11 Right NINC * 0 to 255 * NINC equals a calculated number based on the IR sensor and IR thermistor values used to calculate the NPRG. - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 12 Left NINC MODE VALUE POINTER Pointer Number DESCRIPTION Value Displayed 20 mode range in delta counts 0 to 9999 21 Current mode position (in counts) 0 to 9999 22 mode target position in ratio 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 23 mode target position in counts 0 to 9999 24 Not Used 0 to 0 25 number of valve moves since last index 0 to 9999 26 Not Used 0 to 0 27 Not Used 0 to 0 28 Not Used 0 to 0 29 mode motor state 0 to 5 - 0 = in position, 1 = moving toward panel, 2 = moving toward defrost, 3 = searching range, 4 = stalled moving toward panel, 5 = stalled moving toward defrost - LEFT SIDE TEMPERATURE POINTER Pointer Number DESCRIPTION Value Displayed 30 Left side temp range in delta counts 0 to 9999 31 Current left side temp position (in counts) 0 to 9999 32 Left side temp target position (in ratio) 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 33 Left side temp target in counts 0 to 9999 34 Not used 0 to 0 35 number of valve moves since last index 0 to 9999 36 Not used 0 to 0 37 Not used 0 to 0 38 Not used 0 to 0 39 Left side temp motor state 0 to 5 - 0 = in position, 1 = moving toward panel, 2 = moving toward defrost, 3 = searching range, 4 = stalled moving toward panel, 5 = stalled moving toward defrost - RIGHT SIDE TEMPERATURE POINTER Pointer Number DESCRIPTION Value Displayed 40 Right side temp range in delta counts 0 to 9999 41 Current right side temp position (in counts) 0 to 9999 42 Right side temp target position (in ratio) 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 43 Right side temp target in counts 0 to 9999 44 Not used 0 to 0 45 number of valve moves since last index 0 to 9999 46 Not used 0 to 0 47 Not used 0 to 0 48 Not used 0 to 0 49 Right side temp motor state 0 to 5 - 0 = in position, 1 = moving toward panel, 2 = moving toward defrost, 3 = searching range, 4 = stalled moving toward panel, 5 = stalled moving toward defrost - AIR INLET POINTER Pointer Number DESCRIPTION Value Displayed 50 Air inlet range (in counts) 0 to 9999 51 Current air inlet position (in counts) 0 to 9999 52 Air inlet target position (in ratio) 0 to 255 - While the value of this pointer is being displayed, turning the right set temperature control either direction will manually control the value. CW = increase; CCW = decrease - 53 Air inlet target in counts 0 to 9999 54 Not used 0 to 0 55 number of motor moves since last index 0 to 9999 56 Not used 0 to 0 57 Not used 0 to 0 58 Not used 0 to 0 59 Air inlet motor state 0 to 5 - 0 = in position, 1 = moving toward panel, 2 = moving toward defrost, 3 = searching range, 4 = stalled moving toward panel, 5 = stalled moving toward defrost - 60 Reserved - 61 Actual Outside Air Temp (in degrees F)-40 to 215 62 Not used 0 to 0 63 Engine Intake Air Temperature (in degrees F)-40 to 215 64 Vehicle speed in MPH 0 to 255 65 Engine RPM/100 -0 to 82 66 Engine Coolant Temp - 40 (in degrees F)-40 to 215 67 Country Code 0 to 255 68 Not used 0 to 0 69 Not used 0 to 0 IR SENSOR POINTER Pointer Number DESCRIPTION Value Displayed 70 Thermistor temp (in degrees)-40 to 215 71 Left side sensor A/D (filtered) 0 to 255 72 Right side sensor A/D (filtered) 0 to 255 73 Left side temp (in degrees F)-40 to 140 74 Right side temp (in degrees F)-40 to 140 75 Not used 0 to 0 76 Not used 0 to 0 77 Not used 0 to 0 78 Not used 0 to 0 79 Not used 0 to 0 IDENTIFICATION POINTER Pointer Number DESCRIPTION Value Displayed 80 ROM bit pattern number (digits 1,2,3 & 4) 0 to 9999 81 ROM bit pattern number (digits 5,6,7 & 8) 0 to 9999 82 CAL bit pattern number (digits 1,2,3 & 4) 0 to 9999 83 CAL bit pattern number (digits 5,6,7 & 8) 0 to 9999 84 Not used 0 to 0 85 Not used 0 to 0 86 Not used 0 to 0 87 Not used 0 to 0 88 Not used 0 to 0 89 Not used 0 to 0 OUTPUT CIRCUIT/ACTUATOR TESTS In the Output Circuit/Actuator Test mode, the output circuits can be viewed, monitored, overridden, and tested. If a failure occurs in an output circuit, test the circuit by overriding the system. Test the actuator through its full range of operation. To begin the Output Circuit/Actuator Tests you must be in the Select Test mode. With a "00" value displayed in the Test Selector and no stick man, turn the rotary temperature control knob until the test number you are looking for appears in the Test Selector display. See the Circuit Testing charts for a listing of the test numbers, test items, test types, system tested, and displayed values. To see the output value, depress the A/C or Recirc button. The values displayed will represent the output from the AZC control module. To enter the actuator test, depress the A/C or Recirc button. Then, rotate the right temperature set knob to the desired position.