Automatic A/c-Heater Systems: Diagnosis Mazda Millenia I рестайлинг

SYMPTOM TESTS

PRELIMINARY INSPECTION

Operate A/C-heater system to verify customer's concerns. Carefully check for damaged/loose connections, misrouted wiring circuits, and/or blown fuses. Repair or replace as necessary. If problem(s) remain after repairs have been made, check Diagnostic Trouble Codes (DTCs). See SELF DIAGNOSTICS . If no codes exist, diagnose system by symptom and perform appropriate system test. See SYMPTOM DIAGNOSIS IDENTIFICATION table.

SYMPTOM DIAGNOSIS IDENTIFICATION

TEST NO. 1: ON-BOARD DIAGNOSTIC FUNCTION INOPERATIVE

1. Turn ignition on. Measure voltage at Blue/White wire of A/C amplifier 26-pin (2000) or 20-pin (2001) harness connector. If voltage is zero volts, go to next step. If voltage is not zero volts, repair Blue/White wire between A/C amplifier and ground.
2. Measure voltage at Pink/Green wire of A/C amplifier 26-pin harness connector (2000) or 20-pin harness connector (2001). If battery voltage is present, go to next step. If battery voltage is not present, repair open and/or short in Pink/Green wire between A/C amplifier and RADIO fuse (10-amp) in joint box.
3. Measure voltage at Green wire of A/C amplifier 22-pin (2000) or 16-pin (2001) harness connector. If battery voltage is present, replace A/C amplifier. If battery voltage is not present, repair Green wire between A/C amplifier and A/C fuse (10-amp) in joint box.

Scheme 10

1. Turn ignition on. Set blower switch to fourth speed position. Measure voltage at Blue/Red wire terminal of blower motor harness connector. If battery voltage is present, go to next step. If battery voltage is not present, go to step 8.
2. Measure voltage at Black/White wire terminal of blower motor harness connector. If voltage is zero volts, replace blower motor. If voltage is not zero volts, go to next step.
3. Measure voltage at Black/White wire in power transistor harness connector. (Scheme 10) If battery voltage is present, go to next step. If battery voltage is not present, repair open or short circuit in Black/White wire between blower motor and power transistor. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
4. Turn ignition to LOCK position. Disconnect power transistor harness connector. (Scheme 10) Using DVOM, check continuity of Black wire between power transistor harness connector and ground. If continuity exists, go to next step. If continuity does not exist, repair open circuit in Black wire between power transistor and ground. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
5. Disconnect A/C amplifier 26-pin harness connector (2000) or 20-pin connector (2001). Disconnect blower motor harness connector. Using DVOM, check continuity of Black/White wire between A/C amplifier harness connector and blower motor harness connector. If continuity exists, go to next step. If continuity does not exist, repair open or short circuit in Black/White wire between A/C amplifier harness connector and blower motor harness connector.
6. Using DVOM, check continuity of Blue/Red wire between blower motor harness connector and A/C amplifier 26-pin harness connector (2000) or 20-pin connector (2001). If continuity exists, go to next step. If continuity does not exist, repair open or short circuit in Blue/Red wire between A/C amplifier harness connector and blower motor harness connector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
7. Check power transistor. See «POWER TRANSISTOR»(ref-98829-S33439994722001052600000) under COMPONENT TESTS. Replace as necessary. If power transistor operates as specified, internal transistor has failed. Replace power transistor. Recheck system operation. If blower motor does not operate, replace A/C amplifier.
8. Measure voltage at Black/Yellow wire (2000) or Black wire (2001) terminal of blower relay harness connector. If voltage is zero volts, go to next step. If voltage is not zero volts, go to step 12 (2000 models only). On 2001 models, repair open circuit in Black wire between blower relay harness connector and ground. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
9. Measure voltage at Red/White wire (2000) or Red/Green wire (2001) terminal of blower relay harness connector. If battery voltage is present, go to next step. If battery voltage is not present, repair open and/or short in Red/White wire or Red/Green wire between BLOWER fuse (15-amp on 2000; 10-amp on 2001 models) in joint box and blower relay.
10. Measure voltage at Blue wire terminal of blower relay harness connector. If battery voltage is present, go to next step. If battery voltage is not present, repair open or short circuit in Blue wire between blower relay harness connector and HEATER fuse (40-amp) in main fuse block. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
11. Measure voltage at Blue/Red wire terminal of blower relay harness connector. If battery voltage is present, repair wiring harness between blower relay and blower motor. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000). If battery voltage is not present, replace blower relay.
12. Measure voltage at Black/Yellow wire terminal of A/C amplifier 26-pin harness connector. If voltage is zero volts, repair open or short circuit in Black/Yellow wire between blower relay and A/C amplifier. If voltage is not zero volts, replace A/C amplifier.

TEST NO. 3: AIR INTAKE ACTUATOR INOPERATIVE

1. Remove air intake actuator. Turn ignition on. Place blower switch in fourth speed position. Manually operate air intake crank. If air intake crank operates smoothly from recirculated air to fresh air, go to next step. If air intake crank does not operate smoothly, inspect blower unit.
2. Test air intake actuator. See «AIR INTAKE ACTUATOR»(ref-98829-S25957044752001052600000) under COMPONENT TESTS. If actuator is okay, go to next step. Replace air intake actuator if it does not test as specified.
3. Turn ignition switch to LOCK position. Disconnect A/C amplifier 26-pin harness connector (2000) or 16-pin and 20-pin harness connectors (2001). Check continuity between terminals of air intake actuator harness connector and A/C amplifier harness connector(s). See «AIR INTAKE - A/C AMPLIFIER CONTINUITY (2000)»(ref-98829-S26372592562001052600000) or «AIR INTAKE - A/C AMPLIFIER CONTINUITY (2001)»(ref-98829-S17085961872001060700000) tables. If continuity exists, replace A/C amplifier. If continuity does not exist, repair appropriate wire(s).

AIR INTAKE - A/C AMPLIFIER CONTINUITY (2000)

AIR INTAKE - A/C AMPLIFIER CONTINUITY (2001)

TEST NO. 4: ELECTRICAL LOAD IDLE-UP INOPERATIVE

1. Turn ignition on. Measure voltage at Violet/White wire terminal of A/C amplifier 26-pin harness connector (2000) or 20-pin harness connector (2001). If battery voltage is present, go to next step. If battery voltage is not present, check continuity of Violet/White wire between A/C amplifier and Engine Control Module (ECM). If wire is okay, check ECM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
2. Set blower switch at fourth speed setting. Measure voltage at Violet/White wire of A/C amplifier 26-pin harness connector. If voltage is zero volts, check ECM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If voltage is not zero volts, replace A/C amplifier.

TEST NO. 7: INFORMATION DISPLAY INDICATORS DO NOT ILLUMINATE

1. If any information display indicators illuminate, go to next step. If no information display indicators illuminate, go to step 4 .
2. Disconnect A/C amplifier 26-pin harness connector (2000) or 8-pin harness connector (2001). Disconnect information display harness connector. Using DVOM, check continuity of Yellow/Black and Green/White wires between A/C amplifier harness connector and information display harness connector. If continuity exists on both circuits, go to next step. If continuity does not exist on either circuit, repair open circuit as necessary. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .
3. Disconnect A/C amplifier 22-pin harness connector (2000) or 8-pin harness connector (2001). Using DVOM, check continuity of White/Green and Yellow/Red wires between A/C amplifier harness connector and information display harness connector. If continuity exists in both circuits, replace A/C amplifier or information display as necessary. If continuity does not exist in both wires, repair open circuit between A/C amplifier harness connector and information display harness connector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .
4. Using DVOM, check continuity to ground by backprobing at A/C amplifier 22-pin harness connector Green wire (2000) or 8-pin harness connector Violet wire (2001). If continuity exists, go to next step. If continuity does not exist, replace A/C amplifier.
5. Disconnect A/C amplifier 26-pin harness connector (2000) or 8-pin harness connector (2001). Disconnect information display unit harness connector. Using DVOM, check continuity of Green wire (2000) or Violet wire (2001) between A/C amplifier harness connector and information display harness connector. If continuity exists on both circuits, check for faulty information display unit. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. If continuity does not exist on either circuit, repair open circuit as necessary. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .

TEST NO. 8: SET TEMPERATURE INDICATOR DOES NOT CHANGE

1. Turn ignition switch to ON position. Using DVOM, measure voltage at White/Black wire of A/C amplifier 22-pin harness connector (2000) or 8-pin connector (2001). If voltage is about 3.6 volts (2000) or 3.8 volts (2001), go to next step. If voltage is not as specified, replace A/C amplifier.
2. Hold AMB switch in ON position. Using DVOM, measure voltage at White/Black wire of A/C amplifier 22-pin harness connector (2000) or 8-pin connector (2001). If voltage is zero volts, replace A/C amplifier. If voltage is not zero volts, go to next step.
3. Turn AMB switch to OFF position. Using DVOM, measure voltage at White/Black wire of instrument display unit connector. If voltage is about 3.6 volts (2000) or 3.8 volts (2001), replace instrument display unit. If voltage is not as specified, repair open or short circuit in White/Black wire between A/C amplifier and instrument display unit. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .

TEST NO. 9: SYSTEM ALWAYS STARTS WHEN SPECIFIED TEMPERATURE IS SET

Using DVOM, measure voltage in Blue/Red wire at A/C amplifier 26-pin harness connector (2000) or 20-pin connector (2001). If battery voltage is present, replace A/C amplifier. If battery voltage is not present, repair open or short circuit between A/C amplifier and ROOM fuse (15-amp) in underdash fuse box. See WIRING DIAGRAMS .

TEST NO. 10: MAGNETIC CLUTCH, CONDENSER FAN & A/C COMPRESSOR IDLE-UP INOPERATIVE

1. Inspect A/C refrigerant pressure switch. See «REFRIGERANT PRESSURE SWITCH»(ref-98829-S17693150222001052600000) under COMPONENT TESTS. Replace as necessary. If A/C refrigerant pressure switch is okay, go to next step.
2. Disconnect A/C refrigerant pressure switch harness connector. Using DVOM, measure voltage at Green wire of A/C refrigerant pressure switch harness connector. If voltage is about 5 volts, reconnect A/C refrigerant pressure switch harness connector and go to next step. If voltage is not about 5 volts, check for open or short circuit in Green wire between A/C refrigerant pressure switch harness connector and PCM. Check PCM inputs. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Repair as necessary.
3. Using DVOM, measure voltage in Green/Black wire at A/C amplifier 22-pin harness connector (2000) or 20-pin harness connector (2001). If voltage is about 5 volts, go to next step. If voltage is not about 5 volts, repair open or short circuit between A/C amplifier harness connector and A/C refrigerant pressure switch harness connector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .
4. Set blower switch to fourth speed position. Turn A/C switch to ON position. Using DVOM, measure voltage in Green/Black wire at A/C amplifier 22-pin harness connector (2000) or 20-pin harness connector (2001). If voltage is about 3.1-3.5 volts or less than 1.5 volts, check PCM inputs. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Repair as necessary. If voltage is not as specified, replace A/C amplifier.

TEST NO. 11: COMPRESSOR CLUTCH & CONDENSER FAN INOPERATIVE

1. Locate condenser fan relay at front of engine compartment. (Scheme 11) Using DVOM, measure voltage at Red/Blue wire of condenser fan relay No. 1 connector terminal. If battery voltage is present, go to next step. If battery voltage is not present, check for blown AD FAN fuse (30-amp) in underhood main fuse block. Replace as necessary. Repair open or short circuit in Red/Blue wire between AD FAN fuse (30-amp) and condenser fan relay No. 1 connector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
2. Turn ignition switch to ON position. Using DVOM, measure voltage at Black/White wire of condenser fan relay No. 1 connector terminal. If battery voltage is present, check PCM inputs. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Repair as necessary. If battery voltage is not present, check for blown ENGINE fuse (15-amp). Repair open or short circuit in Black/White wire between ENGINE fuse (15-amp) and condenser fan relay No. 1 connector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).

Scheme 11

TEST NO. 12: COMPRESSOR CLUTCH INOPERATIVE

1. Connect jumper wire between ground and Light Green/Yellow (2000) or Light Green/Red (2001) wire of A/C relay harness connector. Turn ignition on. If compressor clutch does not engage, go to next step. If compressor clutch engages, use DVOM to check continuity of Light Green/Yellow wire or Light Green/Red wire between A/C relay and Engine Control Module (ECM). See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) . Repair as necessary. If wire is okay, inspect ECM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
2. Using DVOM, measure voltage at Blue/Red wire terminal of A/C relay harness connector. If battery voltage is not present, go to next step. If battery voltage is present, go to step 5 .
3. Using DVOM, measure voltage at Red/Blue wire terminal of A/C relay harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair Red/Blue wire between AD FAN fuse (30-amp) in main fuse block and A/C relay. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .
4. Using DVOM, measure voltage at Black/White wire terminal of A/C relay harness connector. If battery voltage exists, replace A/C relay. If battery voltage does not exist, repair Black/White wire between ENGINE fuse (15-amp) in joint box and A/C relay.
5. Measure voltage at Blue/Red wire terminal of thermal protector harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair Blue/Red wire between A/C relay and thermal protector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .
6. Measure voltage at Black wire terminal of thermal protector harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, replace thermal protector.
7. Turn ignition off. Measure continuity between compressor clutch harness connector and compressor body. Continuity should exist. If continuity is as specified, check clutch adjustment. See «COMPRESSOR CLUTCH»(ref-98829-S06311754502001052600000) under ADJUSTMENTS. If continuity is not as specified, replace compressor clutch and retest system.

TEST NO. 13: CONDENSER FAN INOPERATIVE

1. Connect jumper wire between ground and Red/White wire (2000) or Brown wire (2001) terminal of condenser fan relay No. 1 harness connector. (Scheme 11) Turn ignition on. If condenser fan does not operate, go to next step. If condenser fan operates, check continuity of Red/White wire between condenser fan relay No. 1 and Engine Control Module (ECM). See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000). Repair as necessary. If wire is okay, inspect ECM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
2. Measure voltage at Blue/Green wire (2000) or Blue/Yellow wire (2001) terminal of condenser fan relay No. 1 harness connector. If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
3. Measure voltage at Red/Blue wire terminal of condenser fan relay No. 1 harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair Red/Blue wire between AD FAN fuse (30-amp) in main fuse block and condenser fan relay No. 1. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000).
4. Measure voltage at Black/White wire terminal of condenser fan relay No. 1 harness connector. If battery voltage exists, replace condenser fan relay No. 1. If battery voltage does not exist, repair Black/White wire between ENGINE fuse (15-amp) in joint box and condenser fan relay No. 1.
5. Measure voltage at Blue/Green (2000) or Blue/Yellow wire (2001) wire terminal of condenser fan harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair Blue/Green wire between condenser fan and condenser fan relay No. 1.
6. Measure voltage at Green wire terminal of condenser fan harness connector. If voltage is zero volts, test condenser fan. See «CONDENSER FAN»(ref-98829-S18883424412001052600000) under COMPONENT TESTS. If voltage is not zero volts, repair Green wire between condenser fan and condenser fan relay No. 2.

TEST NO. 14: CONDENSER FAN INOPERATIVE AT LOW SPEED

Check continuity of Green wire between condenser fan and cooling fan relay. See WIRING DIAGRAMS . Repair as necessary. If wires are okay, inspect cooling fan system.

TEST NO. 15: CONDENSER FAN INOPERATIVE AT HIGH SPEED

1. Connect jumper wire between ground and Red/White wire (2000) or Brown wire (2001) terminal of condenser fan relay No. 1 harness connector. (Scheme 11) Connect second jumper wire between ground and Yellow wire terminal of condenser fan relay No. 2 harness connector. Turn ignition on.
2. If condenser fan does not operate, go to next step. If condenser fan operates, check continuity of Yellow wire between condenser fan relay No. 2 and Engine Control Module (ECM). If necessary, repair Yellow wire. If wire is okay, inspect ECM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
3. Measure voltage at Black/White wire terminal of condenser fan relay No. 2 harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair open circuit in Black/White wire between ENGINE fuse (15-amp) in joint box and condenser fan relay No. 2.
4. Measure voltage at Black wire terminal of condenser fan relay No. 2 harness connector. If voltage is zero volts, go to next step. If voltage is not zero volts, repair Black wire between condenser fan relay No. 2 and ground.
5. Measure voltage at Green wire terminal of condenser fan relay No. 2 harness connector. If voltage is zero volts, repair Green wire between condenser fan and condenser fan relay No. 2. If voltage is not zero volts, replace condenser fan relay No. 2.

TEST NO. 16: AIRFLOW VOLUME CHANGES ACCORDING TO VEHICLE SPEED

Note. Test 16 is not applicable to 2001 models.

TEST NO. 18: AIR FROM VENTS NOT COLD ENOUGH

1. Test A/C system performance. See «A/C SYSTEM PERFORMANCE»(ref-98829-S03678677262001052600000) . If system pressures are not as specified, diagnose and repair system accordingly. See «REFRIGERANT SYSTEM DIAGNOSIS DIRECTORY»(ref-98829-S41127758162001052600000) table. If high pressure and low pressure readings are the same, check for improper A/C compressor operation. See «TEST NO. 19: COMPRESSOR NOISE»(ref-98829-S14935870982001052600000) . REFRIGERANT SYSTEM DIAGNOSIS DIRECTORY High Pressure Reading Low Pressure Reading Go To Step More Than Specification More Than Specification 2 Less Than Specification Less Than Specification 3 (1) (2) 4 (3) Negative Pressure 5 (1) Slightly less than specification. (2) Slightly more than specification. (3) Momentarily rises to specified range, then drops to less than specification.
2. Check for clogged or damaged condenser fins. Repair as necessary. Ensure there is sufficient refrigerant in system. If condenser fins are not clogged or damaged, check if there is too much refrigerant in system. Adjust as necessary.
3. Perform a refrigerant system leak test. If leak or oil stains exist, repair as necessary. If leak and oil stains are not present, check for insufficient refrigerant caused by occasional leakage. Correct refrigerant level if necessary.
4. Check if heat-sensing tube is properly positioned and securely connected to evaporator outlet pipe. Reinstall tube if necessary. If tube is properly positioned and secured, replace expansion valve.
5. Turn blower switch off and wait about 10 minutes. Place blower switch in fourth speed position. Check pressure readings immediately after compressor is turned on. If pressure readings are normal, expansion valve is clogged due to frozen moisture. Replace receiver-drier.
6. If pressure readings are not normal, check if heat-sensing tube is properly positioned. Reinstall tube if necessary. If tube is properly positioned, replace expansion valve.

TEST NO. 19: COMPRESSOR NOISE

Note. Brief compressor noise immediately following compressor start-up is considered normal.

1. If compressor noise occurs after replacing refrigerant system components, go to next step. If noise occurs during refrigerant charge or if charging system after replacing a component, go to step 5 . If noise occurs at excessively low idle, adjust idle speed. If noise does not occur as described, go to step 3 .
2. Ensure refrigerant oil is properly added after replacing a component. For evaporator unit replacement, add 1.7 ounces of refrigerant oil. For condenser replacement, add 0.7 ounce of refrigerant oil. For receiver-drier replacement, add 0.3 ounce of refrigerant oil. For refrigerant line replacement, add 0.3 ounce of refrigerant oil. If refrigerant oil has been properly added, go to step 5 .
3. Check for correct refrigerant charge. If refrigerant charge is okay, go to next step. If refrigerant charge is incorrect, adjust as necessary.
4. Turn ignition switch to LOCK position. Check for oil stains. If oil stains do not exist, go to next step. If oil stains exist, repair as necessary.
5. Operate engine at constant speed of 3000-4000 RPM. Alternately turn compressor on and off (turn A/C switch on and off). If noise persists, turn ignition off for 1-2 minutes. Restart engine and operate it at constant speed of 3000-4000 RPM. Alternately turn compressor on and off. If noise remains, replace compressor.

SELF-DIAGNOSTICS

Note. Self-diagnostics are written specifically for use with New Generation Start (NGS) Tester (49 T088 001) with appropriate adapters. Generic scan tools can be used but may have limited functions.

Present Diagnostic Test Mode

Electrical faults that are currently occurring in the A/C-heater system are detected and indicated as Diagnostic Trouble Codes (DTCs).

Past Diagnostic Test Mode

Electrical faults that previously occurred in the A/C-heater system (intermittent problems) are detected and identified as Diagnostic Trouble Codes (DTCs).

ENTERING SELF-DIAGNOSTICS

Note. If self-diagnostics cannot be entered, go to TEST NO. 1: ON-BOARD DIAGNOSTIC FUNCTION INOPERATIVE under SYMPTOM TESTS.

1. Start and warm engine to normal operating temperature. Turn ignition off. Insert Program Card (49 T088 002) into NGS Tester (49 T088 001). (Scheme 12) Connect NGS tester to battery, and Super MECS Adapter (49 T088 003) to Data Link harness connector (DLC), using Adapters (49 T088 002, 49 T088 005 and 49 T088 006). Place Super MECS adapter to AUX 1 setting.
2. Select VEHICLE & ENGINE SELECTION vehicle menu. Select DIAGNOSTIC DATA LINK, then A/C AIR CONDITIONER MODULE from display menu of NGS tester. Enter DIAGNOSTIC TEST MODE. Follow menu on NGS tester for instructions to enter self-diagnostics which will begin with present diagnostic test mode. If DTCs exist, go to next step. If no DTCs exist, go to step 4. NOTE: If no light strikes solar radiation sensor, self-diagnostic system will falsely indicate a fault in solar radiation sensor circuit (DTC 02). Use shop light positioned above solar radiation sensor to keep DTC from setting.
3. Depressing A/C switch to ON position will enter into past diagnostic test mode. NGS tester display should indicate any past DTCs that exist in system memory. See «SELF-DIAGNOSTIC CODE DIRECTORY»(ref-98829-S21828156492001052600000) table. If no DTCs exist, go to next step. To clear past DTCs, depress air intake selector and AUTO switches simultaneously. see scheme 1 NGS tester display should read "1", indicating past codes are erased from memory.
4. Depressing AUTO switch to ON position will enter into output operation check. Display indicator lights of climate control unit will illuminate for 4 seconds. A/C controller will enter into step No. 1 of output operation check. see scheme 9 See «OUTPUT OPERATION CHECK»(ref-98829-S18484932212001052600000).
5. To cycle into next step number, depress air intake selector switch. see scheme 1 Depress air intake selector switch as needed to cycle through to step No. 4. After reaching step No. 4, pressing air intake selector switch again will return to step No. 1. To return to present diagnostic test mode, depress AUTO switch.

SELF-DIAGNOSTIC CODE DIRECTORY

Scheme 12

EXITING SELF-DIAGNOSTICS

To exit self-diagnostics, turn ignition off.

DIAGNOSTIC TROUBLE CODES (DTC) LIST

DTC 2: SOLAR RADIATION SENSOR

1. Test solar radiation sensor. See «SOLAR RADIATION SENSOR»(ref-98829-S38836728072001052600000) under COMPONENT TESTS. If sensor is okay, go to next step. Replace sensor if it does not test as specified.
2. Disconnect A/C amplifier 22-pin (2000) or 16-pin (2001) harness connector. Check continuity of Red/Yellow wire between A/C amplifier harness connector and solar radiation sensor harness connector. If continuity exists, go to next step. If continuity does not exist, repair open in Red/Yellow wire. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .
3. On 2000 models, disconnect A/C amplifier 26-pin harness connector. Check continuity of White wire between solar radiation sensor harness connector and A/C amplifier 26-pin (2000) or 16-pin (2001) harness connector. If continuity exists, replace A/C amplifier. If continuity does not exist, repair open in White wire.

DTC 6 & 7: PASSENGER COMPARTMENT TEMPERATURE (PCT) SENSOR

1. Test passenger compartment temperature sensor. See «PASSENGER COMPARTMENT TEMPERATURE (PCT) SENSOR»(ref-98829-S35209788292001052600000) under COMPONENT TESTS. If sensor is okay, go to next step. Replace sensor if it does not test as specified.
2. Disconnect A/C amplifier 22-pin (2000) or 16-pin (2001) harness connector. Check continuity of White/Violet wire and Green/Orange wire between A/C amplifier harness connector and PCT sensor harness connector. See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) . If continuity exists in both wires, replace A/C amplifier. If continuity does not exist in both wires, repair open in appropriate wire(s).

DTC 10 & 11: EVAPORATOR TEMPERATURE SENSOR

1. Test evaporator temperature sensor. See «EVAPORATOR TEMPERATURE SENSOR»(ref-98829-S09514399832001052600000) under COMPONENT TESTS. If sensor is okay, go to next step. Replace sensor if it does not test as specified.
2. Disconnect A/C amplifier 22-pin (2000) or 16-pin (2001) harness connector. Check continuity of Red/White wire and Green/Orange wire between A/C amplifier harness connector and evaporator temperature sensor harness connector. If continuity exists in both wires, replace A/C amplifier. If continuity does not exist in both wires, repair open in appropriate wire(s). See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .

DTC 12 & 13: AMBIENT TEMPERATURE SENSOR

1. Test ambient temperature sensor. See «AMBIENT TEMPERATURE SENSOR»(ref-98829-S36320547922001052600000) under COMPONENT TESTS. If sensor is okay, go to next step. Replace sensor if it does not test as specified.
2. Disconnect A/C amplifier 22-pin (2000) or 16-pin (2001) harness connector. Check continuity of Red/Green wire (2000), Red/Black wire (2001) and Green/Orange wire between A/C amplifier harness connector and ambient temperature sensor harness connector. If continuity exists in both wires, replace A/C amplifier. If continuity does not exist in both wires, repair open in appropriate wire(s). See «WIRING DIAGRAMS»(ref-98829-S28086467362001052600000) .

A/C AMPLIFIER PIN VOLTAGE TEST (2000)

1. Remove climate control unit and A/C amplifier. See «CLIMATE CONTROL UNIT»(ref-98829-S06174307582001052600000) under REMOVAL & INSTALLATION. Reconnect all A/C amplifier harness connectors. Turn ignition on. Using a DVOM, measure voltage by backprobing indicated terminals of appropriate A/C amplifier harness connector. (Scheme 13)- (Scheme 15). See appropriate 2000 A/C AMPLIFIER PIN VOLTAGE TEST table. Ensure voltage is as specified.
2. If reading is not as specified, check appropriate circuits and input/output devices. see scheme 9 See «OUTPUT OPERATION CHECK»(ref-98829-S18484932212001052600000) under SELF-DIAGNOSTICS. Repair or replace as necessary. If circuits and input/output devices are okay, replace A/C amplifier.

2000 A/C AMPLIFIER PIN VOLTAGE TEST (26-PIN HARNESS CONNECTOR) (1)

2000 A/C AMPLIFIER PIN VOLTAGE TEST (22-PIN HARNESS CONNECTOR) (1)

2000 A/C AMPLIFIER PIN VOLTAGE TEST (20-PIN HARNESS CONNECTOR) (1)

Scheme 13

Scheme 14

Scheme 15

Scheme 16

A/C AMPLIFIER PIN VOLTAGE TEST (2001)

1. Remove climate control unit and A/C amplifier. See «CLIMATE CONTROL UNIT»(ref-98829-S06174307582001052600000) under REMOVAL & INSTALLATION. Reconnect all A/C amplifier harness connectors. Turn ignition on. Using a DVOM, measure voltage by backprobing indicated terminals of appropriate A/C amplifier harness connector. (Scheme 17)- (Scheme 19). See appropriate 2001 A/C AMPLIFIER PIN VOLTAGE TEST table. Ensure voltage is as specified.
2. If reading is not as specified, check appropriate circuits and input/output devices. see scheme 9 See «OUTPUT OPERATION CHECK»(ref-98829-S18484932212001052600000) under SELF-DIAGNOSTICS. Repair or replace as necessary. If circuits and input/output devices are okay, replace A/C amplifier.

2001 A/C AMPLIFIER PIN VOLTAGE TEST (20-PIN HARNESS CONNECTOR) (1)

2001 A/C AMPLIFIER PIN VOLTAGE TEST (16-PIN HARNESS CONNECTOR)

2001 A/C AMPLIFIER PIN VOLTAGE TEST (8-PIN HARNESS CONNECTOR)

Scheme 17

Scheme 18

Scheme 19

CLIMATE CONTROL UNIT PIN VOLTAGE TEST (2001)

1. Remove climate control unit. See «CLIMATE CONTROL UNIT»(ref-98829-S06174307582001052600000) under REMOVAL & INSTALLATION. Reconnect all harness connectors. Turn ignition on. Using a DVOM, measure voltage by backprobing indicated terminals of climate control unit harness connector. (Scheme 17)- (Scheme 19). See «2001 CLIMATE CONTROL UNIT PIN VOLTAGE TEST (20-PIN HARNESS CONNECTOR)»(ref-98829-S28128868482001061300000) table. Ensure voltage is as specified.
2. If voltage is not as specified, check climate control unit. See «CLIMATE CONTROL UNIT»(ref-98829-S16077541482001052600000) under COMPONENT TESTS.

2001 CLIMATE CONTROL UNIT PIN VOLTAGE TEST (20-PIN HARNESS CONNECTOR) (1)