NO.7 NO COOL AIR


id070300804800

7
No cool air.
DESCRIPTION
•  Magnetic clutch does not operate.
POSSIBLE CAUSE
•  A/C compressor system malfunction (Step 2)
•  Incorrect amount of refrigerant (Step 3)
•  A/C switch indicator light malfunction (Step 4 - 6)
•  A/C relay system malfunction (F2, G6: Step 7, 11, 12/WE-C, WL-3, WL-C, WLT-1, WLT-2: Step 7, 11- 13)
•  Refrigerant pressure switch malfunction (Step 8)
•  PCM A/C cut-off control system (Step 9, 23)
•  PCM (IG1 signal) system malfunction (Step 10, 22)
•  Magnetic clutch system malfunction (Step 14)
•  PCM (A/C signal) system malfunction (F2, G6: Step 15 - 17/WE-C, WL-3, WL-C, WLT-1, WLT-2: Step 15, 17)
•  Evaporator A/C amplifier, A/C switch malfunction (Step 18 - 21)

•  When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while doing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions. If there is a problem, check to make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT AIR BLOW OUT
•  Does air blow out?
Yes
Go to the next step.
No
Go to Step 1 of troubleshooting indexes 1, 2.
2
INSPECT A/C COMPRESSOR OPERATION
•  Start engine.
•  Turn both A/C switch and fan switch on.
•  Does A/C compressor operate?
Yes
Go to Step 1 of troubleshooting index 6.
No
Go to the next step.
3
INSPECT REFRIGERANT AMOUNT
•  Inspect refrigerant amount. (See REFRIGERANT SYSTEM PERFORMANCE TEST)
•  Is it okay?
Yes
Go to the next step.
No
Add or subtract refrigerant to specified level, then go to Step 24.
4
CHECK TO SEE WHETHER MALFUNCTION IS IN A/C SWITCH OR ELSEWHERE
•  Does A/C switch indicator light illuminate?
Yes
Go to step 7.
No
Go to the next step.
*5
INSPECT A/C SWITCH POWER SUPPLY CIRCUIT
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Remove airflow mode wire, air intake wire and air mix wire.
•  Remove climate control unit.
•  Remove A/C switch from climate control unit and connect A/C switch connector.
•  Measure voltage at A/C switch terminal C (IG2 signal).
•  Is voltage approximately 12 V?
Yes
Go to the next step.
No
Repair wiring harness between fuse block and A/C switch, then go to Step 24.
*6
INSPECT A/C SWITCH
•  Inspect A/C switch.
•  Is it okay?
Yes
Inspect wiring harness between A/C switch and resistor, then go to Step 24.
No
Replace A/C switch, then go to Step 24.
7
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C RELAY POWER SUPPLY OR ELSEWHERE
•  Are A/C relay power supply fuse okay?
Yes
Go to the next step.
No
Check for short to ground on blown fuse’s circuit.
Repair or replace as necessary.
Install appropriate amperage fuse.
*8
INSPECT TO SEE WHETHER MALFUNCTION IS IN REFRIGERANT PRESSURE SWITCH OR ELSEWHERE
•  Remove radiator grill.
•  Disconnect refrigerant pressure switch connector.
•  Short to harness side connector terminal A and B using a jumper wire.
•  Turn both A/C switch and fan switch on with engine is started.
•  Does cool air blow out?
Yes
Inspect refrigerant pressure switch, then go to Step 24.
No
Undo short, reconnect refrigerant pressure switch connector, then go to the next step.
9
INSPECT FOR DTC IN PCM
•  Connect the M-MDS to DLC-2.
•  Retrieve the PCM DTC.
•  Are throttle position sensor (F2, G6), accelerator position sensor (WE-C, WL-3, WL-C, WLT-1, WLT-2) and ECT sensor related DTCs displayed?
Yes
Go to appropriate DTC troubleshooting procedure.
No
Go to the next step.
10
INSPECT TO SEE WHETHER MALFUNCTION IS IN MAGNETIC CLUTCH CONTROL CIRCUIT OR ELSEWHERE
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Does magnetic clutch operate when A/C relay connector terminal B (IG2 signal) is grounded?
Yes
Go to Step 15.
No
Go to the next step.
*11
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C RELAY POWER SUPPLY CIRCUIT OR ELSEWHERE
•   Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure voltage at the following A/C relay connector terminals:
―  Terminal A (IG2 signal)
―  Terminal C (A/C control signal)
•  Is voltage approximately 12 V?
Yes
Go to the next step.
No
Repair wiring harness between fuse block and A/C relay, then go to Step 24.
*12
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C RELAY OR ELSEWHERE
•  Start engine.
•  Turn both A/C switch and fan switch on.
•  Measure the voltage A/C relay terminal D (A/C control signal).
•  Is voltage approximately 12 V?
Yes
Go to Step 14. (F2, G6)
Go to the next step. (WE-C, WL-3, WL-C, WLT-1, WLT-2)
No
Inspect A/C relay, then go to Step 24.
*13
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C CONTROL CIRCUIT OR ELSEWHERE
•  Disconnect refrigerant pressure switch connector.
•  Start engine.
•   Turn both A/C switch and fan switch on.
•  Measure voltage at refrigerant pressure switch connector (harness-side) terminal A (A/C control signal).
•  Is voltage approximately 12 V?
Yes
Reconnect refrigerant pressure switch connector, then go to the next step.
No
Repair wiring harness between A/C relay and refrigerant pressure switch, then go to Step 24.
*14
INSPECT TO SEE WHETHER MALFUNCTION IS IN MAGNETIC CLUTCH OR WIRING HARNESS (BETWEEN REFIRGERANT PRESSURE SWITCH AND MAGNETIC CLUTCH))
•  Start engine.
•  Turn both A/C switch and fan switch on.
•  Measure voltage at magnetic clutch connector terminal A (A/C control signal).
•  Is voltage approximately 12 V?
Yes
Inspect magnetic clutch, then go to Step 24.
No
Repair wiring harness between A/C relay and magnetic clutch, then go to Step 24. (F2, G6)
Repair wiring harness between refrigerant pressure switch and magnetic clutch, then go to Step 24. (WE-C, WL-3, WL-C, WLT-1, WLT-2)
*15
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C SIGNAL OR ELSEWHERE
•  Turn A/C switch off.
•  Remove glove compartment.
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure voltage at the following A/C amplifier connector terminal B (A/C signal)
•  Is voltage approximately 12 V?
Yes
Go to Step 18.
No
Go to the next step. (F2, G6)
Go to Step 17. (WE-C, WL-3, WL-C, WLT-1, WLT-2)
16
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS BETWEEN REFRIGERANT PRESSURE SWITCH AND A/C AMPLIFER
•  Disconnect the refrigerant pressure switch connector.
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure the voltage refrigerant pressure sensor harness side connector terminal A (A/C signal).
•  Is voltage approximately 12 V?
Yes
Repair wiring harness between A/C amplifier and refrigerant pressure switch, then go to Step 24.
No
Go to the next step.
17
INSPECT TO SEE WHETHER MALFUNCTION IS IN PCM OR WIRING HARNESS (BETWEEN PCM AND A/C AMPLIFIER)
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure voltage at PCM terminal 1Q (F2, G6), 239 (WE-C, WL-3, WL-C, WLT-1, WLT-2) (A/C signal).
•  Is voltage approximately 12 V?
Yes
Repair wiring harness between PCM and A/C amplifier, then go to Step 24.
No
Inspect PCM, then go to Step 24.
18
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C AMPLIFIER RELATED CIRCUIT OR ELSEWHERE
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to LOCK position.
•  Disconnect A/C amplifier connector.
•  Short to harness side connector terminal B and C using a jumper wire.
•  Start engine.
•  Turn both A/C switch and fan switch on.
•  Does cool air blow out?
Yes
Undo short, then go to the next step.
No
Go to Step 20.
19
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C AMPLIFIER OR WIRING HARNESS (BETWEEN FUSE BLOCK AND A/C AMPLIFIER)
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure voltage at the A/C amplifier terminal A (IG2 signal).
•  Is voltage approximately 12 V?
Yes
Inspect A/C amplifier, then go to Step 24.
No
Repair wiring harness between fuse block and A/C amplifier, then go to Step 24.
20
INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C SWITCH OR ELSEWHERE
•   Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Turn the A/C switch on.
•  Turn the fan switch off.
•  Measure voltage at A/C switch terminal A (A/C signal).
•  Is voltage approximately 12 V?
Yes
Go to the next step.
No
Inspect A/C switch, then go to Step 24.
21
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (BETWEEN A/C AMPLIFIER AND A/C SWITCH) OR ELSEWHERE
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure voltage at A/C amplifier terminal C (A/C signal).
•  Is voltage approximately 12 V?
Yes
Go to the next step.
No
Repair wiring harness between A/C amplifier and A/C switch, go to Step 24.
22
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (BETWEEN A/C RELAY AND PCM) OR ELSEWHERE
•  Turn the ignition (F2, G6)/engine (WE-C, WL-3, WL-C, WLT-1, WLT-2) switch to ON position.
•  Measure voltage at PCM terminal 1J (F2, G6), 128 (WE-C, WL-3, WL-C, WLT-1, WLT-2) (A/C signal).
•  Is voltage approximately 12 V?
Yes
Go to the next step.
No
Repair wiring harness between PCM and A/C relay, then go to Step 24.
23
INSPECT A/C CUT-OFF CONTROL RELATED SINGAL
•  Connect the M-MDS to DLC-2.
•  Monitor following PCM PIDs.
―  APP1 (WE-C, WL-3, WL-C, WLT-1, WLT-2)
―  APP2 (WE-C, WL-3, WL-C, WLT-1, WLT-2)
―  TP (F2, G6)
―  ECT
•  Are these monitoring value normal?
Yes
Recheck malfunction symptoms.
No
Replace input signal components, then go to the next step.
24
CONFIRM THAT MALFUNCTION SYMPTOMS DO NOT RECUR AFTER REPAIR
•  Does cool air blow out? (Is refrigerant system performance test result correct?)
Yes
Troubleshooting completed. Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.