2002 HONDA CIVIC Temperature Sensor

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.
11-64
\
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

EVAP System
DTC Troubleshooting (cont'dl
31. While monitoring FTP sensor voltage with theHonda PGM Tester, or measuring voltage betweenECM connector terminals E4 and E14, slowly pump
the vacuum oumD.
ECM CONNECTOR E 13lPI
Wire side ot female terminals
32. Continue to pump vacuum until the voltage drops
to about 1.5 V. Make sure the engine coolant
temperature is still above 95'F 135.C) and your
vacuum pump has no leak.
33. Monitor the voltage for 20 seconds.
Does the voltage drop 1.5V and hold for at least
20 seconds?
YES Inspect the EVAP canister vent shut valve
line and connections.l
NO-Go to step 34.
34. Turn the ignition switch OFF.
35. Discon nect the quick-con nect fitting (A) fromthe
EVAP canister, and plug the canister port {B).
36. Turn the ignition switch ON (ll).
11-184
42. Turn the ignition switch ON (ll).
I
38.
39.
37. While monitoring FTP sensor voltage with theHonda PGM Tester, or measuring voltage betweenECM connector terminals E4 and E 14, slowly pump
the vacuum pump.
ECM CONNECTOR E {31PI
Wire side of lemale terminals
Continue to pump vacuum until the voltage drops
to about 1.5V. Make sure the engine coolant
temperature is still above 95"F (35"C) and your
vacuum pump has no leak.
Monitor the voltage for 20 seconds
Does the voltage hold for at least 20 seconds?
YES Inspecl the fuel tank vapor control lineand
connections.I
NO Go to step 40.
Turn the ignition switch OFF.
Disconnect the purge line hose {A) from the
canister at the metal line and plug the hose (B).
40.
41.

43. While monitoring FTP sensor voltage with the
Honda PGM Tester, or measuring voltage between
ECM connector terminals E4 and E14, slowly pump
the vacuum pump.
ECM CONNECTOR E {31P)
Wire side of female terminals
Continue to pump vacuum until the voltage drops
to about 1.5V. Make sure the engine coolant
temperature is still above 95'F (35'C) and your
vacuum pump has no leak.
Monitor the voltage continuously for 20 seconds.
Does the voltage drop to 1.5 V and hold f or at
least 20 seconds?
YES Inspect the EVAP canister purge valve line
and connections. lf they are OK, perform the EVAP
two way valve test (see page 11-186) and the fuel
tank vapor control valve test (see page 1'l-187) l
NO-Replace the EVAP canister
(see page 11-189).1
44.
45.
11-185

21-2
z t-'5
z t-o
z t-o
21-8
21-9
21-10
21-11
21-14
z t- to
HVAC (Heating, Ventilation, and Air Gonditioningl
Heating and Air Conditioning
SpecialTools
Comoonent Location lndex ........
A/C Service Tios and
Precautions
A,/C Refrigerant Oil
ReDlacement
General Troubleshooting
lnformation
DTC Troubleshooting Index .......
Symptom Troubleshooting
1ndex..............
System Description .....................
Circuit Diagram
DTC Troubleshooting ..................
Recirculation Control Motor
CircuitTroubleshooting .......... 21-25
Heater Control Power and Ground
Circuits Troubleshooting ........ 21-27
Condenser Fan Circuit
Troubleshooting ...................... 21-28
Radiator and Condenser Fans
Common Circuit
Troubfeshooting ...................... 21-29
Compressor Clutch Circuit
Troubleshooting ...................... 21-30
A,/C Pressure Switch Circuit
Troubleshooting ...................... 21-32
Air Mix Control Motor
Test and Reolacement ............. 21-34
Mode Control Motor
Test and Replacement ............. 21-35
Recirculation Control Motor
Test and Reolacement ............. 21-36
Evaporator Temperature Sensor
Reolacement and Test ............. 21-31
Power Transistor Test ................. 21 -38
Heater Control Panel and
Push Switch Assemblv
Removal and Installation ........ 21-38
Dust and Pollen Filter
Reolacement ..21-39
Blower Unit Removal and
lnstallation ...... 21-39
Blower Unit Comoonents
ReDlacement ............................ 21-41
Evaporator Core
Reolacement ..21-42*Heater Unit/Core
ReDlacement ..21-43
Heater Valve Cable
Adjustment .....21-46
CompressorReplacement .......... 21-47
Comoressor Clutch Check .......... 21-48
Comoressor Clutch Overhaul ..... 21-49
Compressor Thermal Protector
Reo1acement ............................ 21-51
Comoressor Relief Valve
Reolacement ............................ 21-51
Condenser Reolacement ............ 21-52
Refrigerant Recovery .................. 21-53
System Evacuation ...................... 21-54
System CharginS ......................... 21-55
Refrigerant LeakTest .................. 21-56
A,/C Svstem Tests ........................ 21-57

HEATER UNIT/COREBeplacement, page 21-43
BLOWEN UNITRemoval and Installation, page 21-39
HEATER VALVE CABLEAdjustment, page 21-46
BLOWER UNIT COMPONENTSReplacement, page 21-41
DUSTAND POLLENFILTERReplacement, page 21'39
RECIRCULATION CONTROL MOTORTest, page 21-36Replacement, page 21-36
MODE CONTROL MOTORTest, page 21-35Replacement, page 21-35
AIR MIX CONTROL MOTORTest, page 21'34Replacement, page 21'34
POWER TRANSISTORTest, page 21-38
HEATER CONTROL PANELRemovaland Installation, page 21 38
PUSH SWITCH ASSEMBLYRemoval and Installation, page 21'38EVAPORATOR TEMPERATURESENSORReplacement, page 21-37Test, page 21-37
21-5

Heating and Air Gonditioning
System Description (cont'dl
The air conditioning system removes heat from the passenger compartment by circulating refrigerant through the
system as shown below.
/
BLOWER FAN
\
\,u
EXPANSION VALVE(Meters the requiredamount of refrigerantinto the evaporator)
A/C PRESSURE SWITCHWhen the refriqerant is below196 kPa (2.0 kgi/cm',28 psi)or above 3,140 kPa (32 kgf/cm'455 psi), the Py'c pressureswitch opens the circuit tothe Py'C switch and stops theair conditioning to protect thecompressor-
RECEIVER/DRYER(Traps debris, andremoves morsturel
APOBATOR TEMPERATURESENSOR
THERMAL PROTECTOR(Opens the compressor clutch circuitwhen the compressot temperaturebecomes too high)
RELIEF VALVE(Relieves pressure at the compressorwhen the pressure is too high)
A/C COMPRESSOR(Suction and comoression)\-^
I HrcH PRESSURE vAPoR
[ '.... -:--l Low PREsSUBE LrourD
tffi Low PREssURE vAPoR
This vehicle uses HFC-134a (R-'134a) refrigerant which does not contain ch lorofluorocarbons. Pay attention to the
following service items:
. Do not mix refrigerants CFC-12 (R-12) and HFC-134a (R-134a). They are notcompatible.. Use onlythe recommended polyalkyleneglycol (PAG ) refrigera nt oil (KElHlN SP '!0) designedfortheR-134a
compressor. Intermixing the recommended (PAG) refrigerant oil with any other retrigerant oil will result in
compressor failu re.. AllAy'C system parts (compressor, discharge line, suction line, evaporator, condenser, receiver/dryer. expansion
valve, O-rings for joints) have to be designed for refrigerant R 134a. Do not exchange with R-'12 parts.
. Use a halogen gas leak detector designed for refrigerant R-134a.. R-12 and R-134a refrigerant servicing equipment are not interchangeable. Use only a recovery/recycling/charging
station that is U.L.-listed and is certified to meet the requirements of SAE J2210 to service R-134a air conditioning
system.. Always recover the refrigerant R-134a with an approved recovery/recycling/charging station before disconnecting
any Ay'C fifting.
/-
CONDENSER(Radiation of heat)
21-12

DTC 14: An Open in the Evaporator
Temperature Sensor Circuit
1. Remove the evaporator temperature sensor (see
page 21-37).
2. Measure the resistance between the No. l and
No. 2 terminals of the evaporator temperature
sensor.x Dip the sensor in ice water, and measure
resistance. Then pour hot water on the sensor, and
check for change in resistance.
EVAPORA
RESISTANCEk0
TOR TEMPERATURE SENSOR
t-lll#l
ll,l,llI UT-TU I---r---T--
t^11c))-l\9/
50 6810 20
TEMPERATURE
ls the tesistance within the specifications shown
on the graph?
YES-Go to step 3.
NO Replace the evaporator temperature
sensor.I
3. Disconnect heater control panel connector B {22P).
86'F30 'c
Terminal side of male terminals
4. Check for continuity between the No. 7 terminal of
heater control panel connector B (22P) and the
No. 1 terminal of the evaporalor temperature
sensor 2P connector.
HEATER CONTROL PANEL CONNECTOR B {22P)Wire side of female terminals
EVAPORATOR TEMPERATURE SENSOR 2P CONNECTORWire side of female terminals
ls there continuity?
YES Go to step 5.
NO Repair open in the wire between the heater
control panel and the evaporator temperature
sensor.I
5. Disconnect heater control panel connector A (14P).
(cont'd)
21-23

Heating and Air Gonditioning
\
DTC Troubleshooting {cont'd)
6. Check for continuity between the No. 2 terminal of
heater control panel connector A (14P) and the
No, 2 terminal of the evaporalor temperature
sensor 2P connector.
HEATER CONTROL PANEL CONNECTOR A {14PIWire side of female terminals
LT GRN
EVAFORATOR TEMPERATURE SENSOR 2P CONNECTORWire side of female terminals
ls there continuity?
YES-Check for loose wires or Door connections at
heater control panel connector A ('l4P) and B l22Pl
and at the evaporator temperature sensor 2P
connector. lf the connections are good, substitute a
known-good heater control panel, and recheck. lf
the symptom/indication goes away, replace the
original heater control panel.l
NO Reoair ooen in the wire between the heater
control panel and the evaporator temperature
sensor.I
21-24
4.
DTC 15: A Short in the Evaporator
Temperature Sensor Circuit
1. Remove the evaporator temperature sensor (see
page 21-37).
2. Test the evaporator temperature sensor (see page
21-37 J.
ls the resistance within the specifications shown
on the graph?
YES Go to step 3.
NO Replace the evaporator temperature
sensor. !
Disconnect heater control panel connector B l22Pl.
Check for continuity between the No. 7 terminal of
heater control panel connector B {22P) and body
ground.
HEATER CONTROL PANEL CONNECTOR B (22P)
Wire side of female terminals
ls there continuity?
YES Repair short to body ground in the wire
betvveen the heater control panel and the
evaporator temperature sensor. I
NO-Substitute a known-good heater control panel,
and recheck. lf the symptom/indication goes away,
replace the original heater control panel.I