2000 HONDA CR-V Fan switch

Throttle Position (TPl Sensor
The scan tool indicates Diagnostic Trouble Code (DTC) P0122: A low input (voltage) problem in the Throttle
Position (TP) sensor circuit.
The TP Sensor is a potentiometer. lt is connocted to the throttle valve shaft. As the throttle position changes, the throftle
position sensor varies the voltage signal to the ECM/PCM.
'97 mod6l:BRUSHHOI,I'ER
OUTPUT VOLTAGE IVI
5
4
3
2
1
0
THROITLEOPCNIiIG
FUTIIHROTTI"E
TP SENSOR 3P CONNECTOR {Cl3OI
vcc2IYEL/BLUI
Wi.6 6ide ot fgmale terminsls
PCM CONNECTOR D I16PI
Wire side of female terminals
(GRN/BLX)
- The MIL h.3 been reoorted on.- OTC m122 b 3tored.
Problem vorificalion:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutrall untilthe radiator fan comes on,then turn the ignition switchOFF.2. Turn the ignition switch ON (ll).
3. Check the throttle position
with the scan tool.
ls there approx. 10% when thethrottle is fully closed andapprox.90% when the throttleis fully opened?
Intormittent feilu?e, 3y3tem is OKat thb iime. Check tor poor con-nodiona or loose wiros at C130tTP loNorl .nd rt th€ PCM.
Check tor an open in the wire{vOC2linel:1. Turn the ignition switch OFF.2. Disconnect the TP sensor 3Pconnector,3. Turn the ignition switch ON lll).il. Measure voltage betweenthe TP sensor 3P connector ter-minals No. 1 and No. 3.
ls there approx.5 V?
Check to. an open in wir6 {VCC2linel:Measure voltage between PCMconnector terminals 010 and D11.
Ch6ck to. an opon or shon in TPsonaol:1. Turn the ignition switch OFF.2, At the sensor side, measureresistance between the TPsensor 3P connector terminalsNo. 1 and No. 2 with the throt-tle fully closed.
Repair open in the wirc betweenPCM {D10} and TP 3ensor.ls there approx. 5 V?
Sub3tituto . known-good PCMand rechock. It proscribed volt-ag. b now availablo. rcplaco th6originsl PCM,
Terminal side of male terminals(cont'd)
(To page 11-104)
1 1-103
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The scan tool indicates Diagnostic Trouble Code (DTC) P0123: A high voltage problem in the Throttle Position
(TP) sensor circuit.
TP SENSOR 3P @]{NECTOR IC13O}
sG2(GnN/Br.XlvocrtYEt /8LU)
{GBIT/BLKI
(cont'd)
11-107
Wiro side of fom.le terminals
PCM CON'{ECTOF D I16PI
Wire side ot female terhinals
The MIL hlr br€n r.9ort.d on.DTC P0123 ir stored.
Pioblom vorificltion:1. Start the ongin6. Hold th€ongine at 3,000 rpm with noload {in Park or neutral) untilth6 radiator fan comes on.then turn the ignition switchOFF,2. Turn the ignition switch ON (ll).
3. Check the throttle position
with the scan tool.
Intarmittant tailuro, ryrtern b OKat this timo. Chock lor poor con-nections or loo3o wir€3 at C130
ITP 3orcorl .nd at tho ECM/FCM.
ls there spprox. 1oyo when thothrottle is Iully closed andapprox.90% when the throttleis tully open€d?
Choct toJ an opcn in th6 TP s6n-3t']:1. Turn the ignition switch OFF.2. Disconnect the TP sensor 3Pconnectol,3. Turn the ignition switch ON (ll).
4. At the wir6 harnoss side, mea-suro voltage betweon thg TPsensor 3P connector t€rminalsNo. 1 and No.3.
ls there approx.5 V?
Chack for an oDan in tha wira(SG2 linel:M6asu16 voltage b6tween PCMconn€ctor terminals Dl0 and D'! 1.
R.pai. opcn in tha wira botwcontho PcM {o111 rnd the TP 3en-3('t,
ls there approx. 5 V?
('97 model)
(To page 11-108)
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The scan tool indicates Diagnostic Trouble Code (DTC) P0132: A high voltage problem in the Primary HeatedOxygen Sensor {Primary HO2S) (Sensor 1) circuit.
'97 - 98 models:
PHO2S
IWHTIsG2IGRN/BLK}
Wire side ot female terminals
PCM CONNECTOR D {16PI
JUMPER WIRE
PHO2S IWHTISG2 IGRN/BLK}
Wire side of temale terminals
I
(cont'dl
11-113
Problem verification:1. Do the ECM/PCM Resot Pro,ceoute,2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on.3. Test-drive with the Ay'T in Eposition (M/T in 4th gear).4. Check the Primary H02S{Sensor 1}output voltage withthe scan tool during decelera-tion using completely closedthrottle.
Intormittent l.ilure, 3ystem ia OKat thb timo. Chcck fo. poor con-nections 01 looso wi.es at C111{Prim!ry HO2S, Sensor 1} andECM/PCM.
Does the voltage stay at 1.0 V
Check for an open in th6 PrimaryH()2S:1. Turn the ignition switch OFF.2. Disconnect the Primary HO2S(Sensor 1) connector-3. Connect the Primary HO25lSensor 1) 4P connector termi-nals No. 1 and No. 2 with ajumper wire.4. Turn the ignition switch ON (ll).5. Check the Primary HO2S(Sensor 1) output voltage withthe scan tool,
ls there 1.0 V or more?
Ch€ck for an opon in the wires(PHO2S, SG2linesl:1. Turn the ignition switch OFF.2. Connect PCM connector ter-minals D7 and Dl1 with a
3. Turn the ignition switch ON (ll).4. Check the Primary HO2S{Sensor 1) output voltage withthe scan tool.
Roprir opon in the wire betweontho PCM {D7 01 D11l and thePrimsry HO2S {S6nsor 1).
ls there 1.0 V or more?
{'97 model}
{To page 11-114)
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'99 - 00 modols:
Th6 Mll has b€on reDortod on.DTC ml32 is itorod.
Problem vorification:'1. Do the ECi!4/PCM Reset Procedure,Start the ongine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on.Check the Primary HO2SlSensor 1) output voltage withthe scan tool during decelela-tion using completely closedthroftle.
Int.rmitt .fi tailuro, syltom b OKat thit tima. Check for poor con-nactiona oi loo3a wirar !t Cltl(Primrry HO2S, S.nror 1) .nd .tth. ECM/FCM.
Doos the voitage stay at 1.5 Vor more?
Check for an opsn in the PrlmaryHO2S:1. Turn the ignition switch OFF.2. Disconnect the Primary HO2S(Sensor 1)connector.3. Connect the Primary HO2S(Sensor 1) 4P connector t6rmi-nals No. 1 and No. 2 with a
iumperwire.4. Turn the ignition switch ON (ll).
5, Check the Primsry H02S(Sensor 1) output voltage withthe scan tool,
lsthere 1.5 V or more?
Check for an op6n in th6 wiro{PHO2S line):1. Turn tho ignition switch OFF.2. Connect ECM/PCM connectorterminals C16 and C18 with a
iumper wire.3. Turn the ignition switch ON lll).4. Check the Primary HO2S(Sensor 1) output voltage withthe scan tool.
Ropair opon in thc wire bc{w.cnthe ECM/PCM {Cl6}.nd thePrimary HO2S {S€nror 1}.ls there 1.5 V or more?
Substituto a known-good ECM/PCM snd rochock. lf 3ymptom/indicetion go€a awry, roplaca thoorigin.l ECM/PCM.
PRIMARY HOzS (S6n!or 1l aPCoNNECTOR lcltl)
Pt()2sIWHTIsG2{GRN/BTJ(I
Wire side of tem6le terminsls
ECM/PCM CONNECTOR C (31P}
IGRN/BLKI
JUMPER WIRE
Wire side ol temale t6rmin6ls
(cont'd)
-1 15
2789
/1617't819120A22
23E29g)31
PHO2S {WHTIsG2
11
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ldle Control System
ldle Air Control llAC) Valve
The scan tool indicates Diagnostic Trouble Code (DTC) Pl508: A probtem in the ldle Air Controt flAC) varvecircuit.
The IAC Valve changes the amount of air bypassing the throttle body in response to a current signal from the ECM/PCM inorder to maintain the proper idle speed.
37 model;
IAC VALVE 2P CONNECTOR {C132}
,f rcp'# IYEL/BI.(II2f-1-d)
Y
Wir€ side of female terminals
PCM CONNECTOR A I32PI
tacvIBLK/BLU)
From AIR To INTAKECLEANER MANIFOLD
Wire side of female terminals
The MIL has beon .eport€d on.OIC Pl508 is sto.ed.
Problem veiification:1. Do the PCM Reset Procedure.2. Start the engine, and warm itup to normal operating tem-perature.
Inte.mittent failure, systcm b OKat thi3 time. Check tor poo. con-nections or loose wircs at C132(lAC v.lvel and at the PCM.
ls DTC Pl508 indicated?
Check lor an open in the wir6{lGPl lins}:1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector.3. Turn the ignition switch ON {ll).4. Measure voltage between bodyground and the IAC valve 2Pconnector term inal No.2.
Repair open in the wire trctwoontha IAC v!lv6 and the PGM-Flmain relly.
Chock for an opan o. short in thowi.e (lACv linel:1. Turn the ignition switch OFFand reconnect the IAC valve2P connector.2. Disconnect the PCM conneclorA (32P).
3. Turn the ignition switch ON {ll).4, Measure voltage betweenbody ground and PCM con-nector terminal A12.
{To page 1l-153)
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The MIL has boen r.ported on.DIC Pl 508 b 3tored.
Problem veritication:L Do the ECM/PCM Reset Pro-cedure.2. Start the engine, and warm itup to normal operating tem-perature.
Int€rmittent failure, systom is OKal lhis timo. Check lor poor con-nections or looro wirca at C132(lAc vrlvel and .t rho EcM/PcM.
ls DTC P1508 indicated?
Chock tor an open in the wir6llGPl linel:1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector,3. Turn the ignition switch ON (ll).4. Measure voltage between bodyground and the IAC valve 2Pcon nector termina I No, 2.
Repair opon in the wira botwoonthe IAC valve and tho PGM-FImain aalay.
Check tor an open or short in thewire (IACV linel:1. Turn the ignition switch OFFand reconnect the IAC valve2P connector.2. Disconnect ECM/PCM con-nector B {25P).3. Turn the ignition switch ON {ll}.4. Measure voltage betweenbody ground and ECM/PCMconnector terminal 823.
Ropair open or short in thg wirebetween tho ECM/FCM lB23l andthe IAC valve.
ls there battery voltage?
Check the IAC valve func,tion:Momentarily connect ECM/PCMconnector terminals 823 and 82with a jumper wire several times.
Does the IAC valve click?
Subslitute . known-good ECM/PCM .nd rechock. lf symptom/indication goes aw.y, replac.th€ original ECM/PCM.
ldle Air Control (lAC) Valve {cont'd}
'98 - 00 models:
IAC VALVE 2P CONNECTOR {C132I
F rcpt*l tYELrBLxlI2/'-- rf)
Y
Wire side ot fem.le terminals
ECM/PCM CONNECTOR B (25PI
Wire side of female torminals
258
9'to1l13t7
1920212223
tAcv(BLK/BLUIv
PG1{BLKI
12 | t3 4 58
910 111317
1920 | 121)22
tAcv(BLK/
BLU)JUMPER WIRE
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Alternator (ALT) FR Signal
This signals the ECM/PCM when the Alternator (ALTI is charging.
,97 modet: PCM GONNECTORS
wire side of female terminals
ALT CONNECTOR (C1O5I
lPr-F- ALT F
lll2llw|{frREDl|3.r-'l-
lruueen wne
c (31P|
wire side ol f€male terminals
PCM CONNECTOR C I31P)
3Pr
JUMPERWIRE
Inspection ot ALT FR Signal.
Check lor a short in the wire
{ALT F line}:1. Disconnect the 4P 13Pi* connector from the ALT.2. Turn the ignition switch ON (ll)
3, Measure voltage betweenPCM connector terminals C17
and A9.Check for a short in the wire(ALT F linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat'tery cable from the battery.3. Disconnect PCM connector C(31P).
4. Check for continuity betweenbody ground and PCM connector terminal C17.
ls there approx. 5 V?
Check th€ ope.ation of the ALT:
1. Turn the ignition switch OFF2. Reconnect the ALT 4P {3Pi*connector to the ALT.3. Start the engine. Hold theengine at 3,000 rpm with no
load (in Park or neutral) untilthe radiator fan comes on,
then let it idle.4. Measure voltage betweenPCM connector terminals C17and A9.
Ropeir short in the wir6 betweonthe PCM lC17l and the ALT.
Substitut. a known-good PCM
and recheck. lf prescribed volt-
age is now availablo, replace the
originalPCM.
Does the voltage decrease when
headlights and rear defogger are
turned on?ALT FR signal b OK.
Ch€d( for an op€n in tho wire IALTF linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat-tery cable lrom the battery.3. Disconnect PCM connector C(31P).
4. Disconnect the 4P (3P)* con-nector lrom the ALT.5. Connect the ALT 4P (3P)* con-nector terminal No. 4 (No. 1)*to body ground with a iumper
6. Check for continuity betweenbody ground and PCN4 con'nector terminal Cl7.
Repair open wi.e between thePCM lCl7l and the ALT.ls there continuity?
ALT F IWHT/REDI
Wire side of female terminals
1 1-159
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ldle Speed Setting
Inspoction/Adiustmont
37 modsl:
NOTE:
. Before setting the idle speed, check the following
items:- The MIL has not been reportsd on.- lgnition timing- Spark plugs
- Air cleaner- PCV system
. lcanada) Pull the parking brake lever up. Stan the
engine, then check that the headlights are off.
1. Start the engine. Hold the engine at 3,000 rpm with
no load (in Park or neutral) until the radiator fan
comes on, then let it idle.
Connect a tachometer or a Honda PGM Tester.
Disconnect the 2P connector from the ldle Air Con-
trol (lAC) valve.
IAC VALVE
lf the engine stalls, restart the engine with the accel-
erator pedal slightly depr6ss6d, Stabilize the rpm at
1,000, then slowly release the pedal until the engine
idles.
Check idling in no-load conditions: hsadlights,
blower fan, rear d€fogger, radiator fan, and air con-
ditioner are not operating.
ldle spood should b.:
{80 t 50 rpm {in Park or noutr.ll
IDLE
7.
Adjust the idle sp6ed,
idle adjusting screw.
if necessary, by turning the
Turn the ignition switch OFF.
Reconnect the 2P connector to the IAC valve, then
remove the BACK UP (RAD|Ol (7.5 Al fuse in the
under-hood fuse/rslav box for 10 seconds to reset
the PCM.
Restart and let the engine idle with no-load condi-
tions for one minute, then check the idle speed.
NOTE: (Canadal Pullthe parking brake lever up. Stan
the engine, then check that the headlights are off.
ldlo Ep€ed rhould be:
75O t 50 rpm (in P.rk or noutr.ll
Let the engine idl6 for one minute with the head-
lights (Low) ON, and check th€ idl€ speed.
ldle lpcod 3hould bo:
750 t 50 ]pm (in Park or nautlal)
Turn the headlights off. Let th€ engine idle for one
minute with the headlights (Low) ON, heater fan
switch at Hl and air conditioner on. then check the idle
sDeeo.
ldl. specd should b6:
7d) 1 50 rpm {in Park or nautral}
lf the idle speed is not within specification, see the
symptom chart on page 11-64. (cont'd)
1 1-169
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