TOYOTA CAMRY 1999 Service Repair Manual

A00379
ON
1 (+)
BE6653S05694
S05742
1
2
± DIAGNOSTICSENGINE (1MZ±FE)
DI±359
594 Author: Date:
INSPECTION PROCEDURE
HINT:

If DTCs ºP0110º (Intake Air Temp. Circuit Malfunction), ºP0115º (Engine Coolant Temp. Circuit Mal-
function), ºP0120º (Throttle/Pedal Position/Switch ºAº Circuit Malfunction), ºP1410º (EGR Valve Posi-
tion Sensor Circuit Malfunction) are output simultaneously, E2 (Sensor Ground) may be open.

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 VC of wire harness side connector and body
ground.
PREPARATION:
(a) Disconnect the vacuum hose from EGR valve.
(b) Disconnect the EGR valve position sensor connector.
(c) Turn the ignition switch ON.
CHECK:
Measure voltage between terminal 1 of wire harness side con-
nector and body ground.
OK:
Voltage: 4.5 ~ 5.5 V
NG Go to step 4.
OK
2 Check EGR valve position sensor.
PREPARATION:
Disconnect the EGR valve position sensor connector.
CHECK:
Measure resistance between terminals 1 (VC) and 2 (E2) of
EGR valve position sensor.
OK:
Resistance: 1.5 ~ 4.3 kW
NG Replace EGR valve position sensor.
OK

A02036
ON
EGLS (+) E2 (±)
DI±360
± DIAGNOSTICSENGINE (1MZ±FE)
595 Author: Date:
3 Check voltage between terminals EGLS and E2 of ECM connectors.
PREPARATION:
(a) Disconnect the vacuum hose from EGR valve.
(b) Connect the hand±held vacuum pump to EGR valve.
(c) Remove the glove compartment (See page SF±73).
(d) Turn the ignition switch ON.
CHECK:
Measure voltage between terminals EGLS and E2 of the ECM
connectors.
OK:
ConditionVltEGR valveVacuumVoltage
Fully closed0 kPa
(0 mmHg, 0 in.Hg)0.4 ~ 1.6 V
Fully open17.3 kPa
(130 mmHg, 5.12 in.Hg)3.2 ~ 5.1 V
NG Check for open and short in harness and
connector between ECM and EGR valve
position sensor (EGLS or E2 line).
OK
Check and replace ECM (See page IN±31).

A02022
ON
VC (+) E2 (±)
± DIAGNOSTICSENGINE (1MZ±FE)
DI±361
596 Author: Date:
4 Check voltage between terminals VC and E2 of ECM connector.
PREPARATION:
(a) Remove the glove compartment (See page SF±73).
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between terminals VC and E2 of the ECM
connector.
OK:
Voltage: 4.5 ~ 5.5 V
NG Check and replace ECM (See page
IN±31).
OK
Check for open and short in harness and
connector between ECM and EGR valve
position sensor (VC line).

DI±362
± DIAGNOSTICSENGINE (1MZ±FE)
597 Author: Date:
DTC P1411 EGR Valve Position Sensor Circuit
Range/Performance Problem
CIRCUIT DESCRIPTION
Refer to DTC P1410 (EGR Valve Position Sensor Circuit Malfunction) on page DI±358.
DTC No.DTC Detecting ConditionTrouble Area
P1411
Conditions (a) and (b) continue for 500 msec. or more:
(2 trip detection logic)
(a) Engine Coolant Temp. < 55C (415F)
(b) EGLS
1.65 V or EGLS < 0.35 V

EGR valve position 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 P1411) being output?
YES Go to relevant DTC chart.
NO
Replace EGR valve position sensor.
DI087±06

A07449
Fusible
Link
Block
FL
MAINStop Light Switch
B±G1B 1CSTOP
WG±WLight
Failure
Sensor 7
2
To Stop Light Instrument Panel J/B
Instrument Panel J/B
E7 15
G±W
1S 1R
1R1
2
F9
F4
BatteryECM
STP
E1 B±R
ALT
G±WA
C
J27Junction
Connector
J2845
2
G±W7 4
1
1
± DIAGNOSTICSENGINE (1MZ±FE)
DI±363
598 Author: Date:
DTC P1520 Stop Light Switch Signal Malfunction
(Only for A/T)
CIRCUIT DESCRIPTION
This signal is used to detect when the brakes have been applied. The STP signal voltage is the same as
the voltage supplied to the stop lights.
The STP signal is used mainly to control the fuel cut±off engine speed (The fuel cut±off engine speed is re-
duced slightly when the vehicle is braking.).
DTC No.DTC Detecting ConditionTrouble Area
P1520
Stop light switch does not turn off when repeating the driving at
30 km or more 10 times or more after depressing brake
(2 trip detection logic)
Short in stop light switch signal circuit

Stop light switch

ECM
WIRING DIAGRAM
DI088±06

A02037
ON
ON
Brake Pedal
DepressedBrake Pedal
Released
STP (+)
DI±364
± DIAGNOSTICSENGINE (1MZ±FE)
599 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 operation of stop light.
CHECK:
Check if the stop lights go on and off normally when the brake pedal is operated and released.
NG Check and repair stop light circuit.
OK
2 Check STP signal.
When using TOYOTA hand±held tester:
PREPARATION:
(a) Connect the TOYOTA hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the TOYOTA hand±
held tester main switch ON.
CHECK:
Read the STP signal on the TOYOTA hand±held tester.
OK:
Brake pedal is depressed: STP ...... ON
Brake pedal is released: STP ...... OFF
When not using TOYOTA hand±held tester:
PREPARATION:
Turn the ignition switch ON.
CHECK:
Check voltage between terminal STP of the ECM connector
and body ground.
OK:
Brake pedalVoltage
Depressed7.5 ~ 14 V
ReleasedBelow 1.5 V
OK Check for intermittent problems
(See page DI±197).
NG

± DIAGNOSTICSENGINE (1MZ±FE)
DI±365
600 Author: Date:
3 Check harness and connector between ECM and stop light switch
(See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±31).

S05470
Battery FL
MAIN B±G
F4
F61 1
18
B Fusible
Link
BlockEngine Room J/B No.2
2A2JB±YECM
BATT EFI
E71 DI±366
± DIAGNOSTICSENGINE (1MZ±FE)
601 Author: Date:
DTC P1600 ECM BATT Malfunction
CIRCUIT DESCRIPTION
Battery positive voltage is supplied to terminal BATT of the ECM even when the ignition switch is OFF for
use by the DTC memory and air±fuel ratio adaptive control value memory, etc.
DTC No.DTC Detecting ConditionTrouble Area
P1600Open in back up power source circuit
Open in back up power source circuit

ECM
HINT:
If DTC P1600 appear, the ECM does not store another DTC.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because free 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.
DI089±06

A02038
LOCK
BATT (+)
S04162
Engine Room J/B
EFI Fuse
± DIAGNOSTICSENGINE (1MZ±FE)
DI±367
602 Author: Date:
1 Check voltage between terminal BATT of ECM connector and body ground.
PREPARATION:
Remove the glove compartment (See page SF±73).
CHECK:
Measure voltage between terminal BATT of the ECM connector
and body ground.
OK:
Voltage: 9 ~ 14 V
OK Check and replace ECM (See page IN±31).
NG
2 Check EFI fuse.
PREPARATION:
Remove the EFI fuse from the engine room J/B.
CHECK:
Check continuity of EFI fuse.
OK:
Continuity
NG Check for short in all harness and components
connected to EFI fuse.
OK
Check and repair harness or connector be-
tween battery and EFI fuse, and EFI fuse and
ECM (See page IN±31).

DI±368
± DIAGNOSTICSENGINE (1MZ±FE)
603 Author: Date:
DTC P1780 Park/Neutral Position Switch Malfunction
CIRCUIT DESCRIPTION
The park/neutral position switch go on when the shift lever is in the N or P shift position. When it goes on
terminal NSW of the ECM is grounded to body ground via the starter relay, thus the terminal NSW voltage
becomes 0V. When the shift lever is in the D, 2, L or R position, the park/neutral position switch goes off,
so the voltage of ECM. Terminal NSW becomes battery voltage, the voltage of the ECM internal power
source. If the shift lever is moved from the N position to the D position, this signal is used for air±fuel ratio
correction and for idle speed control (estimated control), etc.

DTC No.DTC Detecting ConditionTrouble Area
2 or more switches are ON simultaneously for ºNº, º2º, ºLº and
ºRº positions
(2 trip detection logic)
Sh t i k/ t l iti it h i it
P1780When driving under conditions (a) and (b) for 30 sec. or more
the park/neutral position switch is ON (N position):
(2 trip detection logic)
(a) Vehicle speed: 70 km/h (44 mph) or more
(b) Engine speed: 1,500
NE and 2,500 rpm
Short in park/neutral position switch circuit

Park/neutral position switch

ECM
HINT:
After confirming DTC P1780, use the TOYOTA hand±held tester to confirm the PNP switch signal from
ºCURRENT DATAº.
WIRING DIAGRAM
Refer to DTC P1780 on page DI±479.
INSPECTION PROCEDURE
Refer to DTC P1780 (Park/Neutral Position Switch Malfunction) on page DI±479.
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.
DI08A±06