2006 ACURA CSX clutch

SymptomDiagnostic procedure Also check for
21-17


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Blower fan runs slower
than expected in cold
weather (when in
AUTO mode)
NOTE: It is normal for
the blower fan to run
slowly until the coolant
temperature rises
when in AUTO mode
Probable cause: Engine coolant temperature
(ECT) circuit malfunction
Troubleshooting the ECT sensor circuit:
ECT sensor 2 circuit low voltage (see page
11-170)
ECT sensor 2 circuit high voltage (see page
11-172) HVAC DTCs (see page 21-9)
Powertrain DTCs (see page
11-3)
Blower motor operation
The A/C compressor
clutch cycles rapidly on
and off Probable cause: A/C system is very low on
refrigerant, indicating a possible leak
Do the refrigerant leak check (see page 21-93)
and repair any leaks. Replace the receiver/dryer
(see page 21-89), then recharge the system to
specifications (see page 21-92) HVAC DTCs (see page 21-9)
If there is no leak and the
refrigerant level is normal, do
the A/C compressor clutch
circuit troubleshooting
(see page 21-62), and look for
an intermittent problem
Warm air comes out of
the vents, and the high
pressure liquid line is
very hot Probable causes: The A/C system is overcharged
(too much refrigerant), or the condenser is
malfunctioning
Recover A/C refrigerant (see page 21-90), then
check the condenser for restrictions or poor
airflow. Repair as needed. Recharge the system
to specifications (see page 21-92) Incorrect tension or abnormal
wear on the drive belt. Replace
the belt and/or the belt
tensioner as needed
Proper operation of the
condenser/radiator fans. Repair
as needed
Signs of an overheated engine.
Repair as needed
Warm air comes out of
the vents. The suction
line is cool to warm,
and the discharge line
is warm to hot Probable cause: A/C system is low on refrigerant,
indicating a possible leak
Do the refrigerant leak check (see page 21-93)
and repair any leaks. Recharge the system to
specifications (see page 21-92) HVAC DTCs (see page 21-9)
Add refrigerant oil depending
on the part you replaced
(see page 21-7)
Warm air comes out of
the vents. The suction
line is cool to warm,
the discharge line is
warm to hot, and there
is no frost on the
expansion valve Probable cause: Excessive air and/or moisture in
the system, indicating a possible leak
Do the refrigerant leak check (see page 21-93)
and repair any leaks. Replace the receiver/dryer
(see page 21-89), then recharge the system to
specifications (see page 21-92)
HVAC DTCs (see page 21-9)
Check the amount of refrigerant
oil in the system. Adjust the oil
level as needed
Warm air comes out of
the vents. The liquid
line or the condenser
outlet is abnormally
cool, or there is frost or
condensation on the
receiver/dryer Probable cause: A restriction in the high-pressure
side of the system
Recover A/C refrigerant (see page 21-90), then
check the liquid line, the receiver/dryer, and the
condenser for restrictions. Repair as needed.
Recharge the system to specifications (see page
21-92) HVAC DTCs (see page 21-9)
There is heavy frost or
condensation on the
expansion valve, and
frost on the suction line Probable cause: A restriction in the low-pressure
side of the system
Recover A/C refrigerant (see page 21-90), then
check the suction line and the expansion valve
for restrictions. Repair as needed. Recharge the
system to specifications (see page 21-92) HVAC DTCs (see page 21-9)
(cont’d)
08/08/21 14:40:59 61SNR030_210_0018
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DYNOMITE -2009-


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A/C Pressure Sensor
A/C System Pressure Sensor Output
Voltage (V out) System Operation
21-21
99
(1)
140
196
(2)
28 3,138
(32)
455 kPa
(kgf/cm )
psi
V
4.575
0.684
0.425
0.2945
OUTPUT
VOLTAGE
(Vout)
Vcc 5 V Vout GND
A/C PRESSURE2
The A/C pressure sensor converts A/C pressure into electrical signals to the ECM/PCM.




Abnormally low pressure: Below 196 kPa
(2.0 kgf/cm , 28 psi)
Below 0.685 V The ECM/PCM disengages the compressor
clutch. The radiator and condenser fans
operate based on engine coolant temperature.
Normal operating pressure: Above 196 kPa (2.0 kgf/cm , 28 psi)
Below 1,470 kPa (15.0 kgf/cm , 213 psi) 0.686 V to 1.944 V The ECM/PCM cycles the compressor clutch
based on cooling demand. The radiator and
condenser fans operate at low speed unless
the engine coolant temperature exceeds 206 °F.
High operating pressure: Above 1,470 kPa (15.0 kgf/cm , 213 psi)
Below 3,138 kPa (32 kgf/cm , 455 psi) 1.945 V to 4.575 V The ECM/PCM cycles the compressor clutch
based on cooling demand. The radiator and
condenser fans operate at high speed.
Abnormally high pressure: More than
3,138 kPa (32 kgf/cm , 455 psi) Above 4.575 V The ECM/PCM disengages the compressor
clutch. The radiator and condenser fans
operate based on engine coolant temperature.
: The A/C system pressure can be monitored in the HDS PGM-FI Data List.
The response of the A/C pressure sensor is shown in the graph.
(cont’d)
222
2
2
2
08/08/21 14:41:00 61SNR030_210_0022
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DYNOMITE -2009-

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21-26Climate Control
Circuit Diagram
PNK
RED/BLK
12
1 2
Q6
1 2
GRN/REDRED
IG2 HOT in ON (II)
CAN HI
CAN LO
FAN HI ACC L
FAN LO A14
A4
A5 13
A/C COMPRESSOR
2
RED/WHT
BLU
F26 MICU
1
19
21
A37
A36
BLK
A9 A33 A16 A19 PNK
WHT RED
1
23
RED
LT GRN
5V
BLK
VCC6
ACPD
TW2 GRN12
SG BLK
No. 15
(7.5 A)
(20 A) No. 6 A/C DIODE A
GRY RED
WHT
LT GRN
BRN
42 3 5
1 IG2
BAT
ORNNo. 36 (10 A)
BRN
BLK RED
BLU
2
1
G301 ECM/PCM
BATTERY
No. 1 (BAT) (100 A)
24
2
3
PUR
13
41 No. 9 (40 A)
No. 2 (IG) (50 A)
1
3
42
WHT
BLK
G301
No.20(7.5A)
1
3
2
4
PUR
UNDER-HOOD FUSE/RELAY BOX IGNITION SWITCH
UNDER-DASH
FUSE/RELAY BOX
RADIATOR
FAN RELAY
FAN CONTROL
RELAY
A/C
CONDENSER
FAN RELAY A/C
COMPRESSOR
CLUTCH RELAY
BLOWER
MOTOR
RELAY
RADIATOR
FAN
MOTOR
PGM-FI
SUB
RELAY
A/C
CONDENSER
FAN
MOTOR
ENGINE
COOLANT
TEMPERATURE
(ECT) SENSOR 2A/C PRESSURE
SENSOR
GAUGE
CONTROL
MODULE
(TACH)
A/C
COMPRESSOR
CLUTCH
UNDER-DASH
FUSE/RELAY
BOX
THERMAL
PROTECTOR
A/C
DIODE B
H1 C3 Q16
G12
D1
F11 F14 F12 F2 F7 F20 E8 F1 J2 No. 7 (20 A)
08/08/21 14:41:03 61SNR030_210_0027
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DYNOMITE -2009-

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21-62
Climate Control
A/C Compressor Clutch Circuit Troubleshooting
A/C COMPRESSOR CLUTCH RELAY 4P SOCKET
NOTE:
 It is normal for the A/C compressor to turn off under certain conditions, such as low idle, high engine
coolant temperature, or hard acceleration.
 Do not use this troubleshooting procedure if the fans are also inoperative with the A/C on. Refer to the
symptom troubleshooting index.
 Before doing any symptom troubleshooting, check for powertrain DTCs (see page 11-3).
1. Check the No. 20 (7.5 A) fuse in the under-hood fuse/relay box, and the No. 36 (10 A) fuse in the
under-dash fuse/relay box.
Go to step 2.
Replace the fuses and recheck. If the fuses
blow again, check for a short in the No. 20 (7.5 A)
and No. 36 (10 A) fuses circuit.
2. Connect the HDS to the DLC.
3. Start the engine.
4. Turn on the A/C.
5. Using the HDS, confirm the following values in the PGM-FI Data List at idle.
ECT Sensor 2 80 100 °C (176 212 °F)
TP Sensor About 0.5 V at idle
RPM More than 670
A/C Switch ON
A/C Clutch ON
A/C Pressure
Sensor 196 455 kPa (28 455 psi)
Go to step 6.
Troubleshoot the value that is not within the
specifications. 6. Turn the ignition switch to LOCK (0).
7. Remove the A/C compressor clutch relay from the
under-hood fuse/relay box, and test it (see page
22-70).
Go to step 8.
Replace the A/C compressor clutch relay.
8. Measure the voltage between the A/C compressor clutch relay 4P socket terminal No. 1 and body
ground.
Go to step 9.
Replace the under-hood fuse/relay box
(see page 22-65).
Ar e t he f uses OK ?
Are all the values within specif ications? Is the relay OK ?
Is there battery voltage?
08/08/21 14:43:32 61SNR030_210_0063
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21-63
JUMPER WIRE
PUR
A/C COMPRESSOR CLUTCH RELAY 4P SOCKET
A/C COMPRESSOR CLUTCH RELAY 4P SOCKET
BRN ECM/PCM CONNECTOR A (44P)
JUMPER WIRE RED
9. Connect the A/C compressor clutch relay 4P socket
terminals No. 1 and No. 2 with a jumper wire.
Go to step 10.
Go to step 19.
10. Disconnect the jumper wire.
11. Turn the ignition switch to ON (II).
12. Measure the voltage between the A/C compressor clutch relay 4P socket terminal No. 3 and body
ground.
Go to step 13.
Repair open in the wire between the No. 36
(10 A) fuse in the under-dash fuse/relay box and the
A/C compressor clutch relay. 13. Turn the ignition switch to LOCK (0).
14. Reinstall the A/C compressor clutch relay.
15. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the engine
control module (ECM)/powertrain control module
(PCM) from damage.
16. Disconnect ECM/PCM connector A (44P).
17. Connect the ECM/PCM connector A (44P) terminal No. 14 to body ground with a jumper wire.
18. Turn the ignition switch to ON (II). Check for loose wires or poor connections at
ECM/PCM connector A (44P). If the connections are
good, check the ECM/PCM grounds. If the grounds
are good, substitute a known-good ECM/PCM, and
recheck. If the symptom/indication goes away,
replace the original ECM/PCM (see page 11-228).
Repair open in the wire between the A/C
compressor clutch relay and the ECM/PCM.
(cont’d)
Terminal side of female terminals
Does the A/ C compressor clutch click?
Is there battery voltage? Does t he A/ C compr essor cl i ck ?
08/08/21 14:43:33 61SNR030_210_0064
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21-6421-64Climate Control
A/C Compressor Clutch Circuit
Troubleshooting (cont’d)
A/C Signal Circuit Troubleshooting
A/C COMPRESSOR CLUTCH RELAY 4P SOCKET
RED/WHT
A/C COMPRESSOR CLUTCH 3P CONNECTOR PUR
REDBRN
CLIMATE CONTROL UNIT 32P CONNECTOR
19. Disconnect the jumper wire.
20. Disconnect the A/C compressor clutch 3P connector.
21. Check for continuity between the A/C compressor
clutch relay 4P socket terminal No. 2 and the A/C
compressor clutch 3P connector terminal No. 2.
Check the A/C compressor clutch clearance,
and the compressor clutch field coil (see page
21-85). Repair as needed.
Repair open in the wire between the A/C
compressor clutch relay and the A/C compressor
clutch. NOTE:
 Do not use this troubleshooting procedure if any of the following items are operative: A/C condenser fan,
radiator fan, A/C compressor. Refer to the symptom
troubleshooting index.
 Before doing symptom troubleshooting, check for powertrain DTCs (see page 11-3).
1. Connect the HDS to the DLC.
2. Start the engine.
3. Turn on the A/C.
4. Check the A/C SWITCH in the PGM-FI Data List with the HDS.
The A/C signal is OK at this time.
Go to step 5.
5. Turn the ignition switch to LOCK (0), and disconnect the climate control unit 32P connector.
6. Measure the evaporator temperature sensor resistance between the climate control unit 32P
connector terminals No. 8 and No. 19.
Go to step 7.
Test the evaporator temperature sensor
(see page 21-70).
Wire side of female terminals
Wire side of female terminals
Is there continuity?Is the A/ C SW IT CH on?
I s r esi st ance l ess t han 24 k ?
08/08/21 14:43:33 61SNR030_210_0065
ProCarManuals.com
DYNOMITE -2009-



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21-6421-64Climate Control
A/C Compressor Clutch Circuit
Troubleshooting (cont’d)
A/C Signal Circuit Troubleshooting
A/C COMPRESSOR CLUTCH RELAY 4P SOCKET
RED/WHT
A/C COMPRESSOR CLUTCH 3P CONNECTOR PUR
REDBRN
CLIMATE CONTROL UNIT 32P CONNECTOR
19. Disconnect the jumper wire.
20. Disconnect the A/C compressor clutch 3P connector.
21. Check for continuity between the A/C compressor
clutch relay 4P socket terminal No. 2 and the A/C
compressor clutch 3P connector terminal No. 2.
Check the A/C compressor clutch clearance,
and the compressor clutch field coil (see page
21-85). Repair as needed.
Repair open in the wire between the A/C
compressor clutch relay and the A/C compressor
clutch. NOTE:
 Do not use this troubleshooting procedure if any of the following items are operative: A/C condenser fan,
radiator fan, A/C compressor. Refer to the symptom
troubleshooting index.
 Before doing symptom troubleshooting, check for powertrain DTCs (see page 11-3).
1. Connect the HDS to the DLC.
2. Start the engine.
3. Turn on the A/C.
4. Check the A/C SWITCH in the PGM-FI Data List with the HDS.
The A/C signal is OK at this time.
Go to step 5.
5. Turn the ignition switch to LOCK (0), and disconnect the climate control unit 32P connector.
6. Measure the evaporator temperature sensor resistance between the climate control unit 32P
connector terminals No. 8 and No. 19.
Go to step 7.
Test the evaporator temperature sensor
(see page 21-70).
Wire side of female terminals
Wire side of female terminals
Is there continuity?Is the A/ C SW IT CH on?
I s r esi st ance l ess t han 24 k ?
08/08/21 14:43:33 61SNR030_210_0065
ProCarManuals.com
DYNOMITE -2009-


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21-66Climate Control
A/C Signal Circuit Troubleshooting (cont’d)
A/C COMPRESSOR CLUTCH 3P CONNECTOR
GRN/RED RED/BLK
A/C COMPRESSOR CLUTCH 3P CONNECTOR BRN
CLIMATE CONTROL UNIT 32P CONNECTOR
18. Turn the ignition switch to LOCK (0).
19. Disconnect the A/C compressor clutch 3P connector.
20. Turn the ignition switch to ON (II).
21. Measure the voltage between the A/C compressor
clutch 3P connector terminal No. 1 and body
ground.
Go to step 22.
Repair open in the wire between the A/C
compressor and the MICU. If the wire is OK,
substitute a known-good MICU and recheck. If the
symptom goes away, replace the original MICU
(see page 22-66).
22. Test the A/C compressor thermal protector (see page 21-85).
Go to step 23.
Replace the A/C compressor thermal
protector (see page 21-87). 23. Check for continuity between the climate control
unit 32P connector terminal No. 6 and the A/C
compressor clutch 3P connector terminal No. 3.
Check for loose wires or poor connections at
the climate control unit 32P connector and at the
A/C compressor clutch 3P connector.
Repair open in the wire between the climate
control unit and A/C compressor.
Wire side of female terminals Wire side of female terminalsWire side of female terminals
Is there battery voltage?
I s t he A/ C compr essor t her mal pr ot ect or OK ? Is there continuity?
08/08/21 14:43:34 61SNR030_210_0067
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