TOYOTA CAMRY 1999 Service Repair Manual

± DIAGNOSTICSENGINE (5S±FE)
DI±189
424 Author: Date:
6 Check for open in harness and connector between circuit opening relay (Mark-
ing: CIR OPN) and fuel pump, and fuel pump and body ground
(See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±31).

A03610
9
W±L
IK2
E9 10
II3
E9 18
LOCK IN
E1 14
EC
BRJ23
IK2 10
BR 1
2A/C Compressor
Lock SensorECM
BR W±L W±L
B
B BRJ/C
AA
A
BR
II3 J8
6J/C
*1: w/o Immobiliser
*2: w/ Immobiliser(*1) (*2)
E919
BR
E9 24
(*1) (*2)
DI±190
± DIAGNOSTICSENGINE (5S±FE)
425 Author: Date:
A/C Compressor Lock Sencor Circuit
CIRCUIT DESCRIPTION
This sensor sends 1 pulse par engine revolution to the ECM. If the number ratio of the compressor speed
divided by the engine speed is smaller than a predetermined value, the ECM turns the compressor off. And,
the indicator flashes at about 1 second intervals.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check compressor.
PREPARATION:
(a) Check the compressor drive belt tension (See page AC±16).
(b) Check if the compressor does not lock during operation with the engine started and blower switch and
A/C switch ON.
NG Adjust drive belt tension or repair compressor
(See page AC±17).
OK
DI01N±04

N15622
12
N02774
LOCK IN Signal Waveform
20 msec./Division (Idling) 0 V
0.2 V/Div.
± DIAGNOSTICSENGINE (5S±FE)
DI±191
426 Author: Date:
2 Check compressor lock sensor.
PREPARATION:
Disconnect the compressor lock sensor connector.
CHECK:
Measure resistance between terminals 1 and 2 of the compres-
sor lock sensor connector.
OK:
Resistance: 65 ± 125 W at 20°C (68°F)
Reference: Inspection using oscilloscope
During cranking or idling, measure voltage between terminals
LOCK IN and E1 of the ECM.
HINT:
The correct waveform appears as shown in the illustration on
the left.
NG Replace compressor lock sensor
(See page AC±40).
OK
3 Check harness and connector between A/C compressor lock sensor and ECM
(See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±31).

A03611
E8
II2 L±W1
L±R11
THR5 V ECM
E2
E89
BR
II23
BR A/C Evaporator
Temp. Sensor
2 1
*1: w/o Immobiliser
*2: w/ Immobiliser(*1)
(*2)
E810 DI±192
± DIAGNOSTICSENGINE (5S±FE)
427 Author: Date:
A/C Evaporator Temp. Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the temperature inside the cooling unit and sends the appropriate signals to the ECM.
WIRING DIAGRAM
DI01O±04

BE3840
I00180
A03031A03452
ON
E1 (±)
THR (+)
w/o Immobiliser
w/ Immobiliser
E1 (±)THR (+)
AC0175
Thermometer
Ice
Ohmmeter
Thermistor
More than
10 cm (3.94 in.)
± DIAGNOSTICSENGINE (5S±FE)
DI±193
428 Author: Date:
INSPECTION PROCEDURE
1 Check voltage between terminals THR and E2 of ECM connector.
PREPARATION:
(a) Remove the glove compartment (See page SF±64).
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between terminals THR and E1 of the ECM
connector at each temperature.
OK:
Voltage
at 0°C (32 F): 2.2 ± 2.6 V
at 15°C (59°F): 1.4 ± 1.8 V
HINT:
As the temperature increases, the voltage decreases.
OK Check and replace ECM (See page IN±31).
NG
2 Check A/C evaporator temp. sensor.
PREPARATION:
Remove the A/C evaporator temp. sensor
(See page AC±30).
CHECK:
Check resistance between terminals 1 and 2 of the A/C evapo-
rator temp. sensor connector at each temperature.
OK:
Resistance
at 0°C (32°F): 4.6 ± 5.1 W
at 15°C (59°F): 2.1 ± 2.6 W
HINT:
As the temperature increases, the voltage decreases.
NG Replace A/C evaporator temp. sensor.
OK

DI±194
± DIAGNOSTICSENGINE (5S±FE)
429 Author: Date:
3 Check harness and connector between A/C evaporator temp. sensor and ECM
(See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±31).

DI078±08
Vehicle Brought to Workshop
Customer Problem Analysis P. DI±196
Problem Symptom Confirmation
If the engine does not start, perform steps 10 and 12 firstConnect the OBD II scan tool or TOYOTA hand±held tester to DLC3 P. DI±197
If the display indicates a communication fault in the tool, inspect DLC3 P. DI±197
Check DTC and Freezed Frame Data (Precheck)
Record or Print DTC and Freezed Frame Data P. DI±197
Clear DTC and Freezed Frame Data P. DI±197
Visual Inspection
Setting the Check Mode Diagnosis P. DI±197
Symptom Simulation P. IN ± 23
DTC Chart P. DI±211
Problem Symptoms Table P. DI±221
Circuit Inspection P. DI±222
Adjustment, Repair
DTC Check P. DI±197
Titles insideare titles of pages in
in the bottom portion. See the indicated
pages for detailed explanations.this manual with the page number indicated
Malfunction
occurs.Malfunction does not occur.
Parts Inspection
Check for Intermittent Problems P. DI±197
Identification of Problem
Confirmation Test
End 1
2
3
4
5
6
7
108
9
11
12
13
15 14
16
Normal Malfunction code.
17Basic Inspection P. DI±197
± DIAGNOSTICSENGINE (1MZ±FE)
DI±195
430 Author: Date:
ENGINE (1MZ±FE)
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following page.

DI079±02
ENGINE CONTROL SYSTEM Check Sheet
Customer's Name
Driver's Name
Date Vehicle
Brought in
License No.
Model and Model
Year
Frame No.
Engine Model
Odometer Reading
Problem Symptoms
Engine does
not Start
Difficult to
Start
Poor Idling
Poor
Driveability
Engine Stall
Others
Engine does not crankNo initial combustionNo complete combustion
Engine cranks slowly
Other
Incorrect first idleIdling rpm is abnormalHigh ( rpm)Low ( rpm)
Rough idling
Other
HesitationBack fireMuffler explosion (after±fire)Surging
Knocking
Other
Soon after startingAfter accelerator pedal depressed
After accelerator pedal released
During A/C operation
Shifting from N to D
Other
Dates Problem
Occurred
Problem Frequency
Condition When
Problem Occurs
Weather
Engine Operation
Engine Temperature Place Outdoor
TemperatureConstant
Sometimes ( times per day/month)Once only
Other
Fine
CloudyRainySnowyVarious/Other
Hot
Warm CoolCold (approx. °F/ °C)
Highway
SuburbsInner cityUphillDownhill
Rough road
Other
Cold
Warming upAfter warming upAny temperatureOther
Starting
Just after starting ( min.)IdlingRacing
Driving
Constant speedAccelerationDeceleration
A/C switch ON/OFF
Other
Condition of MILRemains on Sometimes light up Does not light up
NormalMalfunction code(s) (code )
Freezed frame data ( )
NormalMalfunction code(s) (code )
Freezed frame data ( )
Normal Mode
(Precheck)
Check Mode DTC InspectionInspector's
Name
km
miles
DI±196
± DIAGNOSTICSENGINE (1MZ±FE)
431 Author: Date:
CUSTOMER PROBLEM ANALYSIS CHECK

DI07A±06
FI0534
A06134
TOYOTA Hand±Held Tester
± DIAGNOSTICSENGINE (1MZ±FE)
DI±197
432 Author: Date:
PRE±CHECK
1. DIAGNOSIS SYSTEM
(a) Description

When troubleshooting OBD II vehicles, the only dif-
ference from the usual troubleshooting procedure
is that you connect to the vehicle the OBD II scan
tool complying with SAE J1978 or TOYOTA hand±
held tester, and read off various data output from
the vehicle's ECM.

OBD II regulations require that the vehicle's on±
board computer lights up the Malfunction Indicator
Lamp (MIL) on the instrument panel when the com-
puter detects a malfunction in the emission control
system/components or in the powertrain control
components which affect vehicle emissions, or a
malfunction in the computer. In addition to the MIL
lighting up when a malfunction is detected, the ap-
plicable Diagnostic Trouble Codes (DTC) pre-
scribed by SAE J2012 are recorded in the ECM
memory (See page DI±211).
If the malfunction does not reoccur in 3 consecutive trips, the
MIL goes off but the DTCs remain recorded in the ECM memory.

To check the DTC, connect the OBD II scan tool or
TOYOTA hand±held tester to Data Link Connector
3 (DLC3) on the vehicle. The OBD II scan tool or
TOYOTA hand±held tester also enables you to
erase the DTC and check freezed frame data and
various forms of engine data (For operating instruc-
tions, see the OBD II scan tool's instruction book.).
DTC include SAE controlled codes and manufac-
turer controlled codes. SAE controlled codes must
be set as prescribed by the SAE, while manufactur-
er controlled codes can be set freely by the
manufacturer within the prescribed limits (See DTC
chart on page DI±211).

DI±198
± DIAGNOSTICSENGINE (1MZ±FE)
433 Author: Date:

The diagnosis system operates in normal mode
during normal vehicle use. It also has a check mode
for technicians to simulate malfunction symptoms
and troubleshoot. Most DTC use 2 trip detection
logic* to prevent erroneous detection, and ensure
thorough malfunction detection. By switching the
ECM to check mode when troubleshooting, the
technician can cause the MIL to light up for a mal-
function that is only detected once or momentarily
(TOYOTA hand±held tester only). (See page
DI±197)

*2 trip detection logic:
When a malfunction is first detected, the malfunc-
tion is temporarily stored in the ECM memory. (1st
trip)
If the same malfunction is detected again during the second
drive test, this second detection causes the MIL to light up. (2nd
trip) (However, the IG switch must be turned OFF between the
1st trip and the 2nd trip.).

Freeze frame data:
Freeze frame data records the engine condition
when a misfire (DTCs P0300 ~ P0306) or fuel trim
malfunction (DTCs P0171, P0172) or other mal-
function (first malfunction only), is detected.
Because freeze frame data records the engine
conditions (fuel system, calculated load, engine
coolant temperature, fuel trim, engine speed, ve-
hicle speed, etc.) when the malfunction is detected,
when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the en-
gine warmed up or not, the air±fuel ratio lean or rich,
etc. at the time of the malfunction.

Priorities for troubleshooting:
If troubleshooting priorities for multiple DTC are given in the ap-
plicable DTC chart, these should be followed.
If no instructions are given troubleshoot DTC according to the
following priorities.
(1) DTC other than fuel trim malfunction (DTCs P0171,
P0172), EGR (DTCs P0401, P0402) and misfire
(DTCs P0300 ~ P0306).
(2) Fuel trim malfunction (DTCs P0171, P0172) and
EGR (DTCs P0401, P0402).
(3) Misfire (DTCs P0300 ~ P0306).