2003 HONDA CIVIC o2 sensor

PGM-FISystem
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DTC Troubleshooting (cont'dl
DTC P0117: ECT Sensor Circuit Low Voltage
1. Turn the ignition switch ON (ll).
2. Check the ECT with the scan tool.
ls 150'C (302'F)or higher (ot H-Limit in Honda
mode of PGM Tester) or 0 V indicated?
YES Go to step 3.
NO Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the ECT sensor and at the ECM. t
3. Disconnect the ECT sensor 2P connector.
4. Check the ECT with the scan tool.
ls 150'C (302"F)or higher (ot H-Limit in Honda
mode ot PGM Tester) or 0 V indicated?
YES-Go to step 5.
NO Replace the ECT sensor. !
5. Turn the ignition switch OFF.
6. Disconnect ECM connector B (24P).
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7. Check for continuity between the ECT sensor 2P
connector terminal No. 1 and bodv oround.
ECT SENSOR 2P CONNECTOR
Wire side of female terminals
ls there continuity?
YES-Repair short in the wire between the ECM(B8) and the ECT sensor.l
NO-Update the ECM if it does not have the latest
software,or substitute a known-good ECM, then
recheck {see page 11-6). lf the symptom/indication
goes away with a known-good EClvl, replace the
original ECM.I

DTC P0118: ECT Sensor Circuit High Voltage
1. Turn the ignition switch ON (ll).
2. Check the ECT with the scan tool.
ls 20'C ( 4'F)or less (or L-Limit in Honda
mode of PGM Tester) or 5 V indicated?
?
5.
YES Go to step 3.
NO lntermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the ECT sensor and at the ECM. I
Turn the ignition switch OFF.
Disconnect the ECT sensor 2P connector.
Connect the ECT sensor 2P connector terminals
No. 1 and No. 2 with a jumper wire.
ECT SENSOR 2P CONNECTOR
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Ecr
-I-l*,
(RED/WHT) {GRN/YEL)
tlJUMPER WIRE
wire side oI Iemale terminals
6. Turn the lgnition switch ON (ll).
1.
8.
9.
10.
Check the ECT with the scan tool.
ls 20"C ( 4"F)or less (or L-Limit in Honda
mode ot PGM Tester) or 5 V indicated?
YES-Go to step 8.
NO Replace the ECT sensor.I
Turn the ignition switch OFF.
Remove the jumper wire.
Connect ECM connector terminals A10 and Bg with
a jumper wire.
ECM CONNECTORS
a {31 P}B {24 P)
Wire side of female terminals
Turn the ignition switch ON (ll).
Check the ECT with the scan tool.
ls 20"C ( 4"F) or less (or L-Limit in Honda
mode of PGM Tester) ot 5 V indicated?
YES - Update the ECM if it does not have the latest
software, or substitute a known-good ECI\4, then
recheck (see page 1 1-6). If the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
NO Repair open in the wire between the ECM
(A10, 88) and the ECT sensor.l
11.
12.
JUMPER WIRE
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PGM-FI System
DTC Troubleshooting (cont'dl
DTC P0122: TP Sensor Circuit Low Voltage
1. Turn the ignition switch oN (111.
2. Check the throttle position with the scan tool.
ls there about 10./. or 0.5 V when the thrcttle is
fully closed and about 90% or 4.5 V when the
throttle is fully opened?
YES Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the TP sensor and at the ECM. t
NO Go to step 3.
3. Turn the ignition switch OFF,
4. Disconnect the TP sensor 3P connector.
5. Turn the ignition switch ON (ll).
6. Measure voltage between the TP sensor 3P
connector terminals No. 1 and No. 3.
TP SENSOR 3P CONNECTOR
Wire side of female terminals
ls there about 5 V?
YES-Go to step 7.
NO Go to step 14.
Turn the ignition switch OFF.1.
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8. At the sensor side, measure resistance between the
TP sensor 3P connector terminals No. 1 and No. 2
with the throttle fully closed.
TP SENSOR 3P CONNECTOR
Terminal side of male terminals
Is there about 0.5 0.9 kQ ?
YES Go to step 9.
NO Replace the throttle body (the TP sensor is not
available separately). I
Measure resistance between the TP sensor 3P
connector terminals No. 2 and No. 3 with the
throttle fully closed.
TP SENSOR 3P CONNECTOB
Terminal side of male terminals
ls there about 4.5k{l ?
YES Go to step 10.
NO Replace the throttle body (the TP sensor is not
available separately). I
10. Disconnect ECM connector A (31P).
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11. At the wire harness side, check for continuity
between TP sensor 3P connector terminal No, 2
and body ground.
TP SENSOR 3P CONNECTOR
1 1213
'PS
REO
Wire side ot Iemale terminals
ls thete continuity?
YES-Repair short in the wire between the ECM
{A15) and the TP sensor.ll
NO-Go to step 12.
Connect ECM connector terminal A15 to body
ground with a jumper wire.
ECM CONNECTOR A 131P)
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,tf$,rr*, ] ;uueen wrne
Wire side oJ .female terminals
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12.
13. At the wire harness side, check for continuity
between TP sensor 3P connector terminal No. 2
and body ground.
TP SENSOR 3P CONNECTOR
(RED/BLX}
Wire side of female terminals
ls there continuity?
YES-Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
NO- Repair open in the wire between the ECM
(A15) and the TP sensor.l
14. lvleasure voltage between ECM connector
terminals 410 and A20.
ECM CONNECTOB A 131P}
vcc2(YEL/8LU)
Wire side of female terminals
ls there about 5 V?
YES Repair open in the wire betlveen the ECM
(A20) and the TP sensor.I
NO Update the ECM if it does nor have the latest
software, or substilute a known-good ECM, then
recheck (see page 1 1-6). lf the symplom indication
goes away with a known-good ECM. replace lhe
original ECM.I
123
TPS
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PGM-FI System
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DTC Troubleshooting (cont'd)
DTC P0123: TP Sensor Circuit High Voltage
1. Turn the ignition switch oN (ll)
2. Check the throttle position with the scan tool.
ls there about 10% or 0.5 V when the throttle is
fully closed and about 90% or 4.5 V when the
throttle is f ully opened?
YES lntermittent failure. system is OK at this time.
Check for poor connections or loose terminals at
the TP sensor and at the ECM, I
NO Go to step 3.
3. Turn the ignition switch OFF.
4. Disconnect the TP sensor 3P connector.
5. Turn the ignition switch ON (ll).
6. At the wire harness side, measure voltage between
the TP sensor 3P connector terminals No. 1 and
No.3.
TP SENSOR 3P CONNECTOR
W;re side of female terminals
ls thete about 5 V?
YES-Replace the throttle body (the TP sensor is
not available separately). I
NO Go to step 7.
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7. Measure voltage between ECM connector
terminals A10 and A20.
ECM CONNECTOR A 131PI
Wire side of female terminals
Is there about 5 V?
YES- Repair open in the wire between the ECM(A10) and the TP sensor. t
NO Update the ECM if it does not have the latest
soflware, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indicationgoes away with a known-good ECM, replace the
original ECM.I

DTC Pl121: TP Sensor Signal Lower Than
Expected
1. Turn the ignition switch ON (ll).
2. Check the throttle position with the scan tool.
ls 12.9'/.,0.6 V, or higher indicated when the
throttle is tully opened?
YES- Intermittent failure, system is OK at this
time.I
NO-Replace the TP sensor (the TP sensor is not
available separately). I
DTCP1122:.fP Sensor Signal Higher Than
Expected
1. Turn the ignition switch ON (ll).
2. Check the throttle position with the scan tool.
ls 12.9 %,0.6 V, or less indicated when the throttle
is f ully closed?
YES Intermittent failure, system is OK at this
time.l
NO Replace the TP sensor (the TP sensor is not
available separately). I
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PGM-FI System
aDTG Troubleshootang (cont'dl
DTC P0128: Cooling System Malfunction
NOTE; lf the DTCS listed below are stored at the same
time as DTC P0128. troubleshoot those DTCS first, thenrecheck for P0128.
P0107, P0108, P1128, P1129: N4anifold absolutepressure (MAP) sensor
P] I06, P1 107, P1 108: Barometric pressure (BARO)
sensor
P1259: VTEC system
P01 16, P01 17, P01 18: Engine coolant temperature (ECT)
sensor
P01 12, P01 13: Intake air temperature (lAT) sensor
P0500: Vehicle speed sensor {VSS)P0335, P0336: Crankshaft position (CKP) sensor
P0300: Random misfire
P0301, P0302, P0303, P0304: No. 1, No. 2, No.3 or No.4
cylinder misfire
P0505: ldle control system malfunction
P1519: ldle air control (lAC)valve
DTC P0128 can occasionally set when the hood is
opened while the engine is running.
1. Check the engine coolant level
Is the engine coolant level low?
VES Refill the engine coolant. lf necessary, repair
the coolant leakage.l
NO Go to step 2.
2. Turn the ignition switch ON (ll), and make sure the
A,/C is off.
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3. Check the radiator fan.
Does the tadiator fan keep running?
YES Checkthe rad iato r fan circuit (see page 10-
14), the radiator fan switch circuit (Short) (see page
10-'16), and the radiator fan switch (see page 10-17).
Also, inspect the ECT and IAT circuits and terminal
connections. lf the circuits, the switch, and the
connections are OK, update the ECI\4 if it does not
have the latest software. or substitute a known-good ECM, then recheck (see page 1 1-6). lf the
symptom/indication goes away with a known-good
ECM, replace the original ECM.I
NO Replace the thermostat (see page 10-8).1

DTC P0134: Ay'F Sensor (Sensor 1) No Activity
Detected
1. Check the attachment state of the A,/F sensor(Sensor 1).
ls it slacked f rom the exhaust pipe?
YES- Reinstall the Ay'F sensor (Seneor 1) (see page
11-113).t
NO-Go to step 2.
2. Reset the ECM (see page 1 1-4).
3. Stan the engine. Hold the engine speed at
3,000rpm with no load (in neutral) until the radiator
fan comes on, then let it idle for 2 minute.
ls DTC PO134 indicated?
YES-Replace the Ay'F sensor {Seneor 1) (see page
11-113).t
NO - Intermittent failu re, sistem is OK at this time.
Check for poor connections or loose terminals at
the Ay'F sensor (Seneor 1 ) and the ECM.I
DTC P0137: Secondary HO2S (Sensor 2)
Circuit Low Voltage
1. Reset the ECM (see page I1-4)
2. Start the engine. Hold the engine at 3,000 rpm wilh
no load (in neutral) until the radiator fan comes on.
3. Check the secondary HO2S (Sensor 2) output
voltage at 3,000 rpm with the scan tool.
ls there 0.3 V or less?
YES Go to step 4.
NO-lntermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the secondary HO2S (Sensor 2) and at the ECM.I
Turn the ignition switch OFF.
Disconnect the secondary HO2S (Sensor 2) 4P
connector.
Turn the ignition switch ON (ll).
Check the secondary HO2S (Sensor 2) output
voltage with the scan tool.
ls there 0.3 V or less?
YES Go to step 8.
NO Replace the secondary HO2S (Sensor 2).1
Turn the ignition switch OFF.
Disconnect ECM connector E (31P).
icont'd)
4.
5.
6.
7.
8.
9.
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