ignition ACURA CSX 2006 Service Repair Manual




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11-340 Fuel Supply System
Fuel Gauge Sending Unit Test
A
A
B
FUEL TANK UNIT 4P CONNECTOR
ORN
LT GRN
NOTE: For the fuel gauge system circuit diagram, refer
to the Gauges Circuit Diagram (see page 22-244). 1. Check the No. 10 METER (7.5 A) fuse in the under- dash fuse/relay box before testing.
2. Check for body electrical system DTCs.  If no DTCs are found, go to step 3.
 If DTC B1175 or B1176 is indicated, go to theindicated DTC’s troubleshooting.
3. Turn the ignition switch to LOCK (0).
4. Remove the rear seat cushion (see page 20-131).
5. Remove the rear floor upper cross-member (A). 6. Remove the access panel (A) from the floor.
7. Disconnect the fuel tank unit 4P connector (B).
8. Measure the voltage between fuel tank unit 4P
connector terminals No. 1 and No. 3 with the
ignition switch ON (II). There should be battery
voltage.
 If the voltage is OK, go to step 9.
 If the voltage is not as specified, check for: – a short in the ORN wire to ground.
– anopenintheORNorLTGRNwire.
9. Turn the ignition switch to LOCK (0).
10. Remove the fuel tank unit from the fuel tank (see page 11-334).
Wire side of female terminals
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11-34111-341
Low Fuel Indicator Test
F
1/2
E LOW
11. Measure the resistance between fuel tank unit 4P
connector terminals No. 1 and No. 3 with the float
at E (EMPTY), LOW (LOW FUEL INDICATOR), 1/2
(HALF FULL), and F (FULL) positions.
If you do not get the following readings, replace the
fuel gauge sending unit (see page 11-338).
F
139.8 mm (5.5 in.) 1/2
72.1 mm (2.8 in.) LOW
19.5 mm (0.77 in.) E
8.9 mm
(0.35 in.)
() 19 to
21 205.8 to
215.8 537.5 to
707 772 to
788
12. Reconnect the fuel tank unit 4P connector.
13. Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds,
then reinstall it.
14. Turn the ignition switch to ON (II).
15. Check that the pointer of the fuel gauge indicates F with the float at F.
 If the pointer of the fuel gauge does not indicate F, replace the gauge assembly.
 If the gauge is OK, the test is complete.
NOTE:  The pointer of the fuel gauge returns to the bottom of the gauge dial when the ignition switch
is turned to ACC or to LOCK (0), regardless of the
fuel level.
 Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds
after completing troubleshooting, otherwise it
may take up to 20 minutes for the fuel gauge to
indicate the correct fuel level. 1. Do the gauge self-diagnostic function (see page
22-241).
 If the low fuel indicator flashes, go to step 2.
 If the low fuel indicator does not flash, replace the gauge control module (tach) (see page
22-277).
2. Check for body electrical system DTCs.
 If any DTCs are indicated, do the indicated DTC’stroubleshooting.
 If no DTCs are indicated, go to step 3.
3. Do the fuel gauge sending unit test (see page 11-340).
Float
Position
Resistance
Terminal side of
male terminals
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11-34111-341
Low Fuel Indicator Test
F
1/2
E LOW
11. Measure the resistance between fuel tank unit 4P
connector terminals No. 1 and No. 3 with the float
at E (EMPTY), LOW (LOW FUEL INDICATOR), 1/2
(HALF FULL), and F (FULL) positions.
If you do not get the following readings, replace the
fuel gauge sending unit (see page 11-338).
F
139.8 mm (5.5 in.) 1/2
72.1 mm (2.8 in.) LOW
19.5 mm (0.77 in.) E
8.9 mm
(0.35 in.)
() 19 to
21 205.8 to
215.8 537.5 to
707 772 to
788
12. Reconnect the fuel tank unit 4P connector.
13. Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds,
then reinstall it.
14. Turn the ignition switch to ON (II).
15. Check that the pointer of the fuel gauge indicates F with the float at F.
 If the pointer of the fuel gauge does not indicate F, replace the gauge assembly.
 If the gauge is OK, the test is complete.
NOTE:  The pointer of the fuel gauge returns to the bottom of the gauge dial when the ignition switch
is turned to ACC or to LOCK (0), regardless of the
fuel level.
 Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds
after completing troubleshooting, otherwise it
may take up to 20 minutes for the fuel gauge to
indicate the correct fuel level. 1. Do the gauge self-diagnostic function (see page
22-241).
 If the low fuel indicator flashes, go to step 2.
 If the low fuel indicator does not flash, replace the gauge control module (tach) (see page
22-277).
2. Check for body electrical system DTCs.
 If any DTCs are indicated, do the indicated DTC’stroubleshooting.
 If no DTCs are indicated, go to step 3.
3. Do the fuel gauge sending unit test (see page 11-340).
Float
Position
Resistance
Terminal side of
male terminals
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Carbon Accumulation Check Throttle Position Learning Check
11-343
Throttle Body Test
A A
NOTE: If the malfunction indicator lamp (MIL) has been
reported on, check for diagnostic trouble code (DTCs).
1. Connect the HDS to the data link connector (DLC) (A) located under the driver’s side of the dashboard.
2. Turn the ignition switch to ON (II).
3. Make sure the HDS communicates with the ECM/ PCM. If it doesn’t, go to the DLC circuit
troubleshooting (see page 11- 204).
4. 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.
5. Check the REL TP SENSOR in the DATA LIST with the HDS. The reading should be below 2.46 deg. If it
is not, clean the throttle body (see page 11- 344).NOTE: If the malfunction indicator lamp (MIL) has been
reported on, check for diagnostic trouble code (DTCs).
1. Connect the HDS to the data link connector (DLC) (A) located under the driver’s side of the dashboard.
2. Turn the ignition switch to ON (II).
3. Make sure the HDS communicates with the ECM/ PCM. If it doesn’t, go to the DLC circuit
troubleshooting (see page 11-204).
4. Select the INSPECTION MENU with the HDS.
5. Do the TP POSITION CHECK in the ETCS TEST. If needed, clean the throttle body (see page 11-344).
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11-34411-344 Intake Air System
Throttle Body Cleaning
Intake Air Bypass Control Thermal
Valve Test
A A A
B
Do not insert your fingers into the installed throttle
body when you turn the ignition switch to ON (II) or
while the ignition switch is ON (II). If you do, you
will seriously injure your fingers if the throttle valve
is activated.
1. Check for damage to the air cleaner. If the air cleaner element is damaged, replace it (see page
11-346).
2. Remove the throttle body; K20Z2 engine (see page 11-348), K20Z3 engine (see page 11-349).
3. Clean off the carbon from the throttle valve and inside the throttle body with a paper towel soaked
in throttle plate and induction cleaner.
NOTE: Remove the throttle body to clean it.
 Be careful not to pinch your fingers.
 To avoid removing the molybdenum coating, do not clean the bearing area of the throttle shaft (A).
 Do not spray throttle plate and induction cleaner directly on the throttle body.
 Use Honda genuine throttle plate and induction cleaner.
4. Install the throttle body (see page 11- 348).
5. Reset the ECM/PCM with the HDS (see page 11-4).
6. Turn the ignition switch to ON (II), and wait 2 seconds.
7. Do the ECM/PCM idle learn procedure (see page 11-310). Vacuum pump/gauge, 0 30 in.Hg, Snap-on YA4000A
or equivalent, commercially available
1. Start the engine, then let it idle. NOTE: The engine coolant temperature must be
below 65 °C (149 °F).
2. Remove the engine cover (see step 1 on page 9-3).
3. Remove the vacuum hose (A) from the intake air duct, and connect a vacuum pump/gauge (B) to the
hose.
4. Raise and lower the engine speed, and make sure the vacuum gauge reading changes as the engine
speed changes.
If the vacuum reading does not change, check for
these problems:
 Misrouted, leaking, broken, or clogged intake air bypass control system vacuum lines.
 A cracked or damaged intake air bypass control thermal valve. Replace the valve if needed
(see page 11-351).
5. 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.
* : This illustration shows K20Z2 engine.
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K20Z2 engine
11-348Intake Air System
Throttle Body Removal/Installation
A
B
C
D
F E
22 N·m
(2.2 kgf·m, 16 lbf·ft)
Do not insert your fingers into the installed throttle body when you turn the ignition switch to ON (II) or while the
ignition switch is ON (II). If you do, there will be serious injury to your fingers if the throttle valve is activated.
NOTE: If you are replacing or cleaning the throttle body, start at step 1. If you are removing the throttle body, start at
step 4. 1. Connect the HDS to the DLC while the engine is stopped.
2. Select the INSPECTION MENU with the HDS.
3. Do the TP POSITION CHECK in the ETCS TEST.
4. Turn the ignition switch to LOCK (0).
5. Remove the intake air duct (A).
6. Disconnect the throttle body connector (B).
7. Disconnect the water bypass hoses (C), and plug them.
8. Disconnect the vacuum hose (D).
9. Remove the throttle body (E).
10. Install the parts in the reverse order of removal with a new gasket (F), then do these:  Refill the radiator with engine coolant (see page 10-8).
 Do the ECM/PCM idle learn procedure (see page 11-310).
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K20Z3 engine
11-349
22 N·m
(2.2 kgf·m, 16 lbf·ft)A
B
C D
E F
D
G
Do not insert your fingers into the installed throttle body when you turn the ignition switch to ON (II) or while the
ignition switch is ON (II). If you do, there will be serious injury to your fingers if the throttle valve is activated.
NOTE: If you are replacing or cleaning the throttle body, start at step 1. If you are removing the throttle body, start at
step 4. 1. Connect the HDS to the DLC while the engine is stopped.
2. Select the INSPECTION MENU with the HDS.
3. Do the TP POSITION CHECK in the ETCS TEST.
4. Turn the ignition switch to LOCK (0).
5. Remove the intake air duct (A).
6. Disconnect the throttle body connector (B).
7. Disconnect the water bypass hoses (C), and plug them.
8. Disconnect the vacuum hoses (D) and the clamp (E).
9. Remove the throttle body (F).
10. Install the parts in the reverse order of removal with a new gasket (G), then do these:  Refill the radiator with engine coolant (see page 10-8).
 Do the ECM idle learn procedure (see page 11-310).
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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 ?
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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?
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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?
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