2000 TOYOTA CAMRY coolant

DI±84
± DIAGNOSTICSENGINE (5S±FE)
319 Author: Date:
DTC P0171 System too Lean (Fuel Trim)
(Except California Spec.)
DTC P0172 System too Rich (Fuel Trim)
(Except California Spec.)
CIRCUIT DESCRIPTION
Fuel trim refers to the feedback compensation value compared against the basic injection time. Fuel trim
includes short±term fuel trim and long±term fuel trim.
Short±term fuel trim is the short±term fuel compensation used to maintain the air±fuel ratio at its ideal
theoretical value. The signal from the heated oxygen sensor indicates whether the air±fuel ratio is RICH or
LEAN compared to the ideal theoretical value, triggering a reduction in fuel volume if the air±fuel ratio is rich,
and an increase in fuel volume if it is lean.
Long±term fuel trim is overall fuel compensation carried out long±term to compensate for continual deviation
of the short±term fuel trim from the central value due to individual engine differences, wear over time and
changes in the usage environment.
If both the short±term fuel trim and long±term fuel trim are LEAN or RICH beyond a certain value, it is
detected as a malfunction and the MIL lights up.
DTC No.DTC Detecting ConditionTrouble Area
P0171
When air±fuel ratio feedback is stable after engine warming up,
fuel trim is considerably in error on RICH side
(2 trip detection logic)

Gas leakage on exhaust system

Air intake (hose loose)

Fuel line pressure

Injector blockage

Heated oxygen sensor (bank 1 sensor 1)

Manifold absolute pressure sensor

Engine coolant temp. sensor
P0172
When air±fuel ratio feedback is stable after engine warming up,
fuel trim is considerably in error on LEAN side
(2 trip detection logic)

Gas leakage on exhaust system

Fuel line pressure

Injector leak, blockage

Heated oxygen sensor (bank 1 sensor 1)

Manifold absolute pressure sensor

Engine coolant temp. sensor
HINT:

When the DTC P0171 is recorded, the actual air±fuel ratio is on the LEAN side. When DTC P0172 is
recorded, the actual air±fuel ratio is on the RICH side.

If the vehicle runs out of fuel, the air±fuel ratio is LEAN and DTC P0171 is recorded. The MIL then
comes on.

If the total of the short±term fuel trim value and long±term fuel trim value is within + 38 %, the system
is functioning normally.

The heated oxygen sensor (bank 1 sensor 1) output voltage and the short±term fuel trim value can
be read using the OBD II scan tool or TOYOTA hand±held tester.
DI4NG±01

± DIAGNOSTICSENGINE (5S±FE)
DI±85
320 Author: Date:
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel ratio lean or rich, etc.
at the time of the malfunction.
1 Check air induction system (See page SF±1).
NG Repair or replace.
OK
2 Check injector injection (See page SF±23).
NG Replace injector.
OK
3 Check manifold absolute pressure sensor and engine coolant temp. sensor
(See pages SF±53 and SF±49).
NG Repair or replace.
OK
4 Check for spark and ignition (See page IG±1).
NG Repair or replace.
OK

± DIAGNOSTICSENGINE (5S±FE)
DI±89
324 Author: Date:
DTC P0300 Random/Multiple Cylinder Misfire Detected
DTC P0301 Cylinder 1 Misfire Detected
DTC P0302 Cylinder 2 Misfire Detected
DTC P0303 Cylinder 3 Misfire Detected
DTC P0304 Cylinder 4 Misfire Detected
CIRCUIT DESCRIPTION
Misfire: The ECM uses the crankshaft position sensor and camshaft position sensor to monitor changes in
the crankshaft rotation for each cylinder.
The ECM counts the number of times the engine speed change rate indicates that misfire has occurred. And
when the misfire rate equals or exceeds the count indicating that the engine condition has deteriorated, the
MIL lights up.
If the misfire rate is high enough and the driving conditions will cause catalyst overheating, the MIL blinks
when misfiring occurs.
DTC No.DTC Detecting ConditionTrouble Area
P0300Mi fi i f d li d i d t t d d i ti l

Ignition system

Injector

Fuel line pressure

EGR
P0300
P0301
P0302
P0303
P0304
Misfiring of random cylinders is detected during any particular
200 or 1,000 revolutions
For any particular 200 revolutions for engine, misfiring is de-
tected which can cause catalyst overheating
(This causes MIL to blink)

EGR

Compression pressure

Valve clearance not to specification

Valve timing

Manifold absolute pressure sensor
P0304(This causes MIL to blink)
Manifold absolute ressure sensor

Engine coolant temp. sensor

Open or short in engine wire

Connector connection

ECM
HINT:
When the 2 or more codes for a misfiring cylinder are recorded repeatedly but no random misfire code is
recorded, it indicates that the misfires were detected and recorded at different times.
DI011±07

DI±92
± DIAGNOSTICSENGINE (5S±FE)
327 Author: Date:
INSPECTION PROCEDURE
HINT:

If is the case that DTC besides misfire is memorized simultaneously, first perform the troubleshooting
for them.

Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame
data records the engine conditions when the malfunction is detected, when troubleshooting it is useful
for determining whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel
ratio lean or rich, etc. at the time of the malfunction.

When the vehicle is brought to the workshop and the misfire is not occurred, misfire can be confirmed
by reproducing the condition or freeze frame data. Also, after finishing the repair, confirm that there
is no misfire. (See the confirmation driving pattern)

When either of SHORT FT #1, LONG FT #1, SHORT FT #2 or LONG FT #2 in the freeze frame data
is besides the range of ±20%, there is a possibility that the air±fuel ratio is inclining either to ºrichº
(±20% or less) or ºleanº (+20% or more).

When COOLANT TEMP in the freeze frame data is less than 80°C (176°F), there is a possibility or
misfire only during warming up.

In the case that misfire cannot be reproduced, the reason may be because of the driving with lack or
fuel, the use of improper fuel, a stain of ignition plug, and etc.
1 Check wire harness, connector and vacuum hose in engine room.
CHECK:
(a) Check the connection conditions of the wire harness and connector.
(b) Check the disconnection, piping and break of the vacuum hose.
NG Repair or replace, then confirm that there is no
misfire (See the confirmation driving pattern).
OK

DI±96
± DIAGNOSTICSENGINE (5S±FE)
331 Author: Date:
8 Check manifold absolute pressure sensor and engine coolant temp. sensor
(See pages SF±53 AND SF±49).
NG Repair or replace.
OK
Check compression pressure, valve
clearance and valve timing
(See pages EM±3, EM±4 AND EM±23).

DI±152
± DIAGNOSTICSENGINE (5S±FE)
387 Author: Date:
DTC P1130 A/F Sensor Circuit Range/Performance
Malfunction (Only for California Spec.)
CIRCUIT DESCRIPTION
Refer to DTC P0125 (Insufficient Coolant Temp. for Closed Loop Fuel Control (Only for California Spec.))
on page DI±61.
DTC No.DTC Detecting ConditionTrouble Area
Voltage output* of A/F sensor remains at 3.8 V or more, or 2.8
V or less, during engine running after engine is warmed up (2
trip detection logic)
*: Output value changes at the inside of ECM only
P1130Voltage output* of A/F sensor does not change from 3.30 V,
during engine running after engine is warmed up
(2 trip detection logic)
*: Output value changes at inside of ECM only
Open or short in A/F sensor circuit

A/F sensor

ECM
Open or short in A/F sensor circuit
(2 trip detection logic)
HINT:

After confirming DTC P1130, use the OBD II scan tool or TOYOTA hand-held tester to confirm voltage
output of A/F sensor (AFS B1 S1 / O2S B1 S1) from the CURRENT DATA.

The A/F sensor's output voltage and the short-term fuel trim value can be read using the OBD II scan
tool or TOYOTA hand-held tester.

The ECM controls the voltage of AF
and AF terminals of ECM to the fixed voltage. Therefore, it
is impossible to confirm the A/F sensor output voltage without OBD II scan tool or TOYOTA hand±held
tester.

OBD II scan tool (excluding TOYOTA hand-held tester) displays the one fifth of the A/F sensor output
voltage which is displayed on the TOYOTA hand-held tester.
WIRING DIAGRAM
Refer to DTC P0125 (Insufficient Coolant Temp. for Closed Loop Fuel Control (Only for California Spec.))
on page DI±61.
DI01D±06

± DIAGNOSTICSENGINE (5S±FE)
DI±157
392 Author: Date:
DTC P1133 A/F Sensor Circuit Response Malfunction
(Only for California Spec.)
CIRCUIT DESCRIPTION
Refer to DTC P0125 (Insufficient Coolant Temp. for Closed Loop Fuel Control (Only for California Spec.))
on page DI±61.
DTC No.DTC Detecting ConditionTrouble Area
P1133
After engine is warmed up, and during vehicle driving at en-
gine speed 1,600 rpm or more and vehicle speed 60 km/h (38
mph) or more, if response characteristic of A/F sensor be-
comes deteriorated
(2 trip detection logic)

A/F sensor
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel ratio lean or rich, etc.
at the time of the, malfunction.
1 Are there any other codes (besides DTC P1133) being output?
YES Go to relevant DTC chart.
NO
DI01E±06

A00430
HTAF (+) ON
± DIAGNOSTICSENGINE (5S±FE)
DI±161
396 Author: Date:
DTC P1135 A/F Sensor Heater Circuit Malfunction
(Only for California Spec.)
CIRCUIT DESCRIPTION
Refer to DTC P0125 (Insufficient Coolant Temp. for Closed Loop Fuel Control (Only for California Spec.))
on page DI±61.
DTC No.DTC Detecting ConditionTrouble Area
P1135
When heater operates, heater current exceeds 8 A
(2 trip detection logic)
Open or short in heater circuit of A/F sensor
A/F h tP1135Heater current of 0.25 A or less when heater operates
(2 trip detection logic)
A/F sensor heater

ECM
WIRING DIAGRAM
Refer to DTC P0125 (Insufficient Coolant Temp. for Closed Loop Fuel Control (Only for California Spec.))
on page DI±61.
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel ratio lean or rich, etc.
at the time of the malfunction.
1 Check voltage between terminal HTAF of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF±64).
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between terminals HTAF of the ECM connec-
tor and body ground.
OK:
Voltage: 9 ~ 14 V
OK Check and replace ECM (See page IN±31).
NG
DI01F±05