2006 ACURA CSX engine coolant

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DTC P0420:
YES
NO YES
NO
YES
NO
11-353
DTC Troubleshooting
Catalyst System Efficiency Below
Threshold
NOTE:
 Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general
troubleshooting information (see page 11-3).
 If some of the DTCs listed below are stored at the same time as DTC P0420, troubleshoot them first,
then recheck for DTC P0420.
P0137, P0138: Sec ondary HO2S (Sensor 2)
P0141: Secondary HO2S (Sensor 2) heater
 Poor quality fuel may cause this DTC.
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in
neutral) until the radiator fan comes on, then let it
idle.
4. Test-drive under these conditions:  Engine coolant temperature (ECT SENSOR 1)above70°C(158°F)
 A/TinD,M/Tin5th
 Vehicle speed between 72 120 km/h (45 75 mph) for 5 minutes or more with cruise
control set
 K20Z2 engine: Maintain the vehicle speed at 88 km/h (55 mph) for 5 minutes or more with
cruise control set
 K20Z3 engine: Maintain the vehicle speed at 88 km/h (55 mph) for 30 seconds or more
5. Monitor the OBD STATUS for DTC P0420 in the DTCs MENU with the HDS.
Go to step 6.
If the screen indicates OUT OF CONDITION,
go to step 4 and recheck. If the screen indicates
PASSED, intermittent failure, the system is OK at
this time. If the screen indicates FAILED, go to step
8.
6. Continue test driving until a result comes on. 7. Monitor the OBD STATUS for DTC P0420 in the
DTCs MENU with the HDS.
Go to step 8.
If the screen indicates PASSED, intermittent
failure, the system is OK at this time. If the screen
indicates EXECUTING, keep driving until a result
comes on. If the screen indicates OUT OF
CONDITION, go to step 4 and recheck.
8. Turn the ignition switch to LOCK (0).
9. Replace the TWC (see page 11-355).
10. Turn the ignition switch to ON (II).
11. Reset the ECM/PCM with the HDS.
12. Do the ECM/PCM idle learn procedure (see page 11-310).
13. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in
neutral) until the radiator fan comes on, then let it
idle.
14. Test-drive for about 10 minutes, varying the vehicle speed.
15. Check the CATA MONITOR CONDITION in the DATA LIST with the HDS.
Go to step 16.
Go to step 13 and recheck.
16. Test-drive under these conditions:  Engine coolant temperature (ECT SENSOR 1)above70°C(158°F)
 A/TinD,M/Tin5th
 K20Z2 engine: Vehicle speed at 88 km/h (55mph) for 5 minutes or more with cruise control set
 K20Z3 engine: Vehicle speed at 88 km/h (55mph) for 30 seconds or more
(cont’d)
Does t he scr een i nd i cat e E X E CU T IN G?Does t he scr een i nd i cat e F AILE D?
Is the condition OK ?
08/08/21 14:31:13 61SNR030_110_0353
ProCarManuals.com
DYNOMITE -2009-

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DTC P0401:
YES
NO
YES
NO YES
NO
YES
NO
11-357
DTC Troubleshooting
EGR Insufficient Flow
NOTE: Before you troubleshoot, record all freeze data
and any on-board snapshot, and review the general
troubleshooting information (see page 11-3).
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in
neutral) until the radiator fan comes on, then let it
idle.
4. Do the EGR TEST in the INSPECTION MENU with the HDS.
Go to step 5.
Go to step 7.
5. Test-drive under these conditions:  Engine coolant temperature (ECT SENSOR 1)above70°C(158°F)
 A/TinD,M/Tin4th
 Drive at a steady speed between 88 120 km/h (55 75 mph) for at least 10 seconds
 During the drive, decelerate (with the throttle fully closed) for 5 seconds
6. Monitor the OBD STATUS for DTC P0401 in the DTCs MENU with the HDS.
RemovetheEGRplate(seepage9-2),and
clean the intake manifold port with throttle plate
and induction cleaner, then go to step 9.
If the screen indicates PASSED, intermittent
failure, the system is OK at this time. Check for
poor connections or loose terminals at the EGR
valve and the ECM/PCM. If the screen indicates
EXECUTING, keep driving until a result comes on. If
the screen indicates OUT OF CONDITION, go to
step 5 and recheck. 7. Turn the ignition switch to LOCK (0).
8. Replace the EGR valve (see page 11-370).
9. Turn the ignition switch to ON (II).
10. Reset the ECM/PCM with the HDS.
11. Do the ECM/PCM idle learn procedure (see page 11-310).
12. Test-drive under these conditions:  Engine coolant temperature (ECT SENSOR 1)above70°C(158°F)
 A/TinD,M/Tin4th
 Drive at a steady speed between 88 120 km/h (55 75 mph) for at least 10 seconds
 During the drive, decelerate (with the throttle fully closed) for 5 seconds
13. Check for Temporary DTCs or DTCs with the HDS.
Check for poor connections or loose
terminals at the EGR valve and the ECM/PCM. If the
connections are OK, go to step 15.
Go to step 14.
14. Monitor the OBD STATUS for DTC P0401 in the DTCs MENU with the HDS.
Troubleshooting is complete. If any other
Temporary DTCs or DTCs were indicated in step 13,
go to the indicated DTC’s troubleshooting.
If the screen indicates FAILED, check for poor
connections or loose terminals at the EGR valve
and the ECM/PCM, then go to step 1. If the screen
indicates EXECUTING, keep driving until a result
comes on. If the screen indicates OUT OF
CONDITION, go to step 12.
(cont’d)
Is the result OK ?
Does t he scr een i nd i cat e F AILE D? Is DT C P0401 ind icated ?
Does t he scr een i nd i cat e PASSE D?
08/08/21 14:31:15 61SNR030_110_0357
ProCarManuals.com
DYNOMITE -2009-

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YES
NO
YES
NO
YES
NO
YES
NO
DTC P0404:
11-35811-358EGR System
DTC Troubleshooting (cont’d)
EGR VALVE 6P CONNECTOR
SG2
EGRP
15. Update the ECM/PCM if it does not have the latest
software (see page 11-227), or substitute a known-
good ECM/PCM (see page 11-7).
16. Test-drive under these conditions:  Engine coolant temperature (ECT SENSOR 1)above70°C(158°F)
 A/TinD,M/Tin4th
 Drive at a steady speed between 88 120 km/h (55 75 mph) for at least 10 seconds
 During the drive, decelerate (with the throttle fully closed) for 5 seconds
17. Check for Temporary DTCs or DTCs with the HDS.
Check for poor connections or loose
terminals at the EGR valve and the ECM/PCM. If the
ECM/PCM was updated, substitute a known-good
ECM/PCM (see page 11-7), then go to step 16. If the
ECM/PCM was substituted, go to step 1.
Go to step 18.
18. Monitor the OBD STATUS for DTC P0401 in the DTCs MENU with the HDS.
If the ECM/PCM was updated,
troubleshooting is complete. If the ECM/PCM was
substituted, replace the original ECM/PCM
(see page 11-228). If any other Temporary DTCs or
DTCs were indicated in step 17, go to the indicated
DTC’s troubleshooting.
If the screen indicates FAILED, check for poor
connections or loose terminals at the EGR valve
and the ECM/PCM. If the ECM/PCM was updated,
substitute a known-good ECM/PCM (see page 11-7),
then go to step 16. If the ECM/PCM was substituted,
go to step 1. If the screen indicates EXECUTING,
keep driving until a result comes on. If the screen
indicates OUT OF CONDITION, go to step 16. NOTE: Before you troubleshoot, record all freeze data
and any on-board snapshot, and review the general
troubleshooting information (see page 11-3).
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in
neutral) until the radiator fan comes on, then let it
idle.
4. Do the EGR TEST in the INSPECTION MENU with the HDS.
Intermittent failure, the system is OK at this
time. Clean any carbon build-up on the EGR valve
with throttle plate and induction cleaner.
Go to step 5.
5. Turn the ignition switch to LOCK (0).
6. Disconnect the EGR valve 6P connector.
7. At the EGR valve side, measure the resistance between EGR valve 6P connector terminals No. 1
and No. 2.
Go to step 25.
Go to step 8.EGR Valve Circuit Range/
Performance Problem
Terminal side of male terminals
I s DT Cs P0401 i nd i cat ed ?
Does t he scr een i nd i cat e PASSE D? Is the result OK ?
Is t her e 100 k or mor e?
08/08/21 14:31:16 61SNR030_110_0358
ProCarManuals.com
DYNOMITE -2009-

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Special Tools Required
13-7
Transmission Removal
A
B C
D
A A
B
A
B C
 Engine hanger adapter
VSB02C000015
 2006 Civic engine hanger VSB02C000025
 Engine support hanger, A and Reds AAR-T 1256
 Front subframe adapter VSB02C000016
These special tools are available through the Acura
Canada Technical Tools Department; FAX
866-398-8665/e-mail: ch_technicaltools ch.honda.com
NOTE: Use fender covers to avoid damaging painted
surfaces.
1. Do the battery removal procedure (see page 22-69).
2. Remove the cowl cover and the under-cowl panel (see page 20-163).
3. Remove the air cleaner assembly (see page 11-345).
4. Remove the harness clips (A) and the intake air duct (B), then remove the battery base (C) with the
coolant reservoir (D). 5. Remove the clutch line bracket (A), then carefully
move the slave cylinder (B) out of the way to avoid
bending the clutch line.
NOTE: Do not press the clutch pedal after the slave
cylinder has been moved.
6. Disconnect the back-up light switch connector (A), the output shaft (countershaft) speed sensor
connector (B), and the harness clips (C).
(cont’d)
08/08/21 14:44:19 61SNR030_130_0009
ProCarManuals.com
DYNOMITE -2009-

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Special Tools Required
13-84
Manual Transmission
Transmission Removal
A
B C
D
A A
B
D
C
A
B
 Engine hanger adapter VSB02C000015
 2006 Civic engine hanger VSB02C000025
 Engine support hanger, A and Reds AAR-T 1256
 Front subframe adapter VSB02C000016
These special tools are available through the Acura
Canada Technical Tools Department; FAX
866-398-8665/e-mail: ch_technicaltools ch.honda.com
NOTE: Use fender covers to avoid damaging painted
surfaces.
1. Do the battery removal procedure (see page 22-69).
2. Remove the cowl cover and the under-cowl panel (see page 20-163).
3. Remove the air cleaner assembly (see page 11-345).
4. Remove the harness clips (A) and the intake air duct (B), then remove the battery base (C) with the
coolant reservoir (D). 5. Remove the clutch line bracket (A), then carefully
move the slave cylinder (B) out of the way to avoid
bending the clutch line.
NOTE: Do not press the clutch pedal after the slave
cylinder has been moved.
6. Disconnect the back-up light switch connector (A), the output shaft (countershaft) speed sensor
connector (B), the r everse lockout solenoid
connector (C), and the harness clips (D).
08/08/21 14:47:19 61SNR030_130_0086
ProCarManuals.com
DYNOMITE -2009-

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Electronic Control System
Functional Diagram
14-39
*1: ’06-07 models
*2: ’08-09 models Engine RPM Signal
Accelerator Pedal
Position Sensor Signal
Barometric Pressure
Sensor Signal
Manifold Absolute
Pressure Sensor Signal
ATF Temperature
Sensor Signal
Service Check SignalTransmission
Range
Switch
Signal
Brake Pedal Position
Switch Signal PGM-FI Control
System
PCM
A/T Control System Shift Control
 Ascending Control
 Descending
Control
 D-paddle Shift
Control

Clutch Pressure
Control
Lock-up Control
Shift Lock Control Shift Lock Solenoid
Vehicle Speed Signal
Data Link Connector Shift Solenoid Valve E
Shift Solenoid Valve D Shift Solenoid Valve C Shift Solenoid Valve B
Shift Solenoid Valve A
F-CAN Line
Automatic
Five-speed and
ReverseLock-up
ON/OFF
Lock-up
Conditions
Sequential
Sportshift
Control Gauge Control Module
(Tach) A/T Gear
Position Indicator
Engine Coolant
Temperature Sensor Signal
2ndClutchTransmission
Fluid Pressure Switch Signal ABS Modulator-Control
Unit Signal (via F-CAN line)*
Output Shaft (Countershaft)
Speed Sensor Signal
Paddle Shifter /
(Upshift/Downshift Switch) 3rdClutchTransmission
Fluid Pressure Switch Signal
1
VSA Modulator-Control
Unit Signal (via F-CAN line)*2
Input Shaft (Mainshaft)
Speed Sensor Signal
Grade Logic Control
Self-diagnosis/
Fail-safe Function
Communication and
Output Function
A/TClutchPressure
Control Solenoid Valve C A/TClutchPressure
Control Solenoid Valve B A/TClutchPressure
Control Solenoid Valve A
The electronic control system consists of the powertrain control module (PCM), sensors, and solenoid valves.
Shifting and lock-up are electronically controlled for comfortable driving under all conditions.
The PCM receives input signals from sensors, switches, and other control units, processes data, and outputs signals
for the engine control system and the A/T control system. The A/T control system includes shift control, grade logic
control, clutch pressure control, and lock-up control.
The PCM switches the shift solenoid valves and the A/T clutch pressure control solenoid valves ON and OFF to control
gear selection and torque converter clutch lock-up.
(cont’d)
08/08/21 14:38:21 61SNR030_140_0041
ProCarManuals.com
DYNOMITE -2009-

Shift Control - Grade Logic Control
14-41
Transmission Range
Switch Signal PCM
Brake Pedal Position
Switch Signal Engine RPM
Control
Engine RPM Signal
Output Shaft
(Countershaft)
Speed Sensor Signal Input Shaft
(Mainshaft)
Speed Sensor Signal
Engine Coolant
Temperature
Sensor Signal Shift Position
Control
Fail-safe Control
Actual Driving
Shift PositionRead of ATF
Temperature
Master Target of
Shifting Position
Correction of Data
Selection of
Shifting Mode
Grade Logic Control
Calculation of
Gradient
Correction of Engine
Coolant Temperature
Sensor Signal Data Shift Solenoid
Valve A
ATF Temperature
Sensor Signal Comparison
with Signals
Accelerator Pedal
Position Sensor Signal
Throttle Position
Sensor Signal
Barometric Pressure
Sensor Signal Shift Solenoid
Valve B
Shift Solenoid
Valve C
Shift Solenoid
Valve D
Shift Solenoid
Valve E
A grade logic control system has been adopted to control shifting in D, and in S with automatic shift mode. The PCM
compares actual driving conditions with programmed driving conditions, based on the input from the accelerator
pedal position sensor, the throttle position sensor, the engine coolant temperature sensor, the barometric pressure
sensor, the brake pedal position switch signal, the output shaft (countershaft) speed sensor signal, and the shift l ever
position signal, to control shifting while the vehicle is ascending or descending a slope.
(cont’d)
08/08/21 14:38:21 61SNR030_140_0043
ProCarManuals.com
DYNOMITE -2009-

ÎClutch Pressure Control
14-45
PCM
Engine RPM Signal
Engine Coolant
Temperature
Sensor Signal Input Shaft
(Mainshaft)
Speed Sensor Signal
Output Shaft
(Countershaft)
Speed Sensor Signal
ATF Temperature
Sensor Signal Actual
Driving Shift
Position
Correction of Data
Correction of Engine
Coolant Temperature
Sensor Data
Manifold Absolute
Pressure Sensor Signal
3rd Clutch
Transmission Fluid
Pressure Switch Signal 2nd Clutch
Transmission Fluid
Pressure Switch Signal
Correction of ATF
Temperature Sensor
Signal Data
Correction of
Hydraulic Pressure
Applying Timing
Correction of Engine
Torque Signal Data Master Target of
Controlling Current
Decision of
Shifting Mode
Ignition Timing
Requirement
PGM-FI
Control
System
Current
Feedback A/T Clutch Pressure
Control Solenoid
Valves A, B, and C
PGM-FI
Control
System
Throttle Position
Sensor Signal
Barometric Pressure
Sensor Signal
The PCM actuates A/T clutch pressure control solenoid valves A, B, and C to control the clutch pressure. When shifting
between lower and higher gears, the clutch pressure regulated by A/T clutch pressure control solenoid valves A, B,
and C engages and disengages the clutch smoothly.
The PCM receives input signals from the various sensors and the switches, processes data, and outputs current to A/T
clutch pressure control solenoid valves A, B, and C.
(cont’d)
08/08/21 14:38:23 61SNR030_140_0047
ProCarManuals.com
DYNOMITE -2009-