1999 TOYOTA CAMRY efi

DI±92
± DIAGNOSTICSENGINE
3 Check circuit opening relay (Marking: CIR OPN) (See Pub. No. RM654U, page
SF±41).
NG Replace circuit opening relay.
OK
4 Check voltage between terminal FC of ECM connector and body ground (See
page DI±86, step 4).
OK Go to step 5.
NG
Check for open in harness and connector between EFI main relay (Marking: EFI) and circuit open-
ing relay (Marking: CIR OPN), and circuit opening relay and ECM (See page IN±29).
5 Check fuel shutoff valve for fuel tank (See page SF±34).
NG Replace.
OK
6 Check for open in harness and connector between circuit opening relay (Mark-
ing: CIR OPN) and fuel shutoff valve for fuel tank, and fuel shutoff valve for fuel
tank and body ground (See page IN±29).
NG Repair or replace harness or connector.
OK

DI±94
± DIAGNOSTICSENGINE
NG
10 Check fuel shutoff valve for delivery pipe (See page SF±28).
NG Replace.
OK
Check for open in harness and connector between EFI main relay (Marking: EFI) and fuel shutoff
valve for delivery pipe, and fuel shutoff valve for delivery pipe and ECM (See page IN±29).

A09425
ON
VCNG3
(±)(+) E01
DI±96
± DIAGNOSTICSENGINE
OK
3 Check voltage between terminals VCNG3 and E01 of ECM connectors.
PREPARATION:
(a) Remove the glove compartment (See Pub. No. RM654U,
page SF±64).
(b) Start the engine.
CHECK:
Measure the voltage between terminals VCNG3 and E01 of the
ECM connectors.
OK:
Voltage: 9 ± 14 V
OK Check and replace ECM (See page IN±29).
NG
4 Check fuel shutoff valve for delivery pipe (See page SF±28).
NG Replace.
OK
Check for open in harness and connector between EFI main relay (Marking: EFI) and fuel shutoff
valve for delivery pipe, and fuel shutoff valve for delivery pipe and ECM (See page IN±29).
OBD II scan tool (excluding TOYOTA hand±held tester):
1 Check for ECM power source circuit (See page DI±116).
NG Repair or replace.
OK

A09425
ON
VCNG3
(±)(+) E01
± DIAGNOSTICSENGINE
DI±97
2 Check voltage between terminals VCNG3 and E01 of ECM connectors.
PREPARATION:
(a) Remove the glove compartment (See Pub. No. RM654U,
page SF±64).
(b) Start the engine.
CHECK:
Measure the voltage between terminals VCNG3 and E01 of the
ECM connectors.
OK:
Voltage: 9 ± 14 V
OK Check and replace ECM (See page IN±29).
NG
3 Check fuel shutoff valve for delivery pipe (See page SF±28).
NG Replace.
OK
Check for open in harness and connector between EFI main relay (Marking: EFI) and fuel shutoff
valve for delivery pipe, and fuel shutoff valve for delivery pipe and ECM (See page IN±29).

A09277
FC ON
(±) (+)
A09424
ON
VCNG2
(±)
(+) E01
± DIAGNOSTICSENGINE
DI±99
3 Check circuit opening relay (Marking: CIR OPN) (See Pub. No. RM654U, page
SF±41).
NG Replace circuit opening relay.
OK
4 Check voltage between terminal FC of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment.
(b) Disconnect the E4 connector from the ECM.
(c) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal FC of the ECM connec-
tor and body ground.
OK:
Voltage 9 ± 14 V
OK Go to step 5.
NG
Check for open in harness and connector between EFI main relay (Marking: EFI) and circuit open-
ing relay (Marking: CIR OPN), and circuit opening relay and ECM (See page IN±29).
5 Check voltage between terminals VCNG2 and E01 of ECM connectors.
PREPARATION:
(a) Remove the glove compartment.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals VCNG2 and E01 of the
ECM connectors.
OK:
Voltage: 9 ± 14 V
OK Check and replace ECM (See page IN±29).
NG

A09424
ON
VCNG2
(±)
(+) E01
± DIAGNOSTICSENGINE
DI±101
OK Go to step 4.
NG
Check for open in harness and connector between EFI main relay (Marking: EFI) and circuit open-
ing relay (Marking: CIR OPN), and circuit opening relay and ECM (See page IN±29).
4 Check voltage between terminals VCNG2 and E01 of ECM connectors.
PREPARATION:
(a) Remove the glove compartment (See Pub. No. RM654U,
page SF±64).
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals VCNG2 and E01 of the
ECM connectors.
OK:
Voltage 9 ± 14 V
OK Check and replace ECM (See page IN±29).
NG
5 Check fuel shutoff valve for fuel pressure regulator (See page SF±30).
NG Replace fuel shutoff valve for fuel pressure reg-
ulator.
OK
Check for open in harness and connector between circuit opening relay (Marking: CIR OPN) and
fuel shutoff valve for fuel pressure regulator, and fuel shutoff valve for fuel pressure regulator
and ECM (See page IN±29).

A09401
Engine Room J/B No.2
EFI11
B
Battery B±G11
2A E4ECM
F9BATT
2JB±Y
F118
FL Block
MAIN FL DI±110
± DIAGNOSTICSENGINE
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 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 was warmed up or not, the air±fuel ratio was lean
or rich, etc. at the time of the malfunction.
DI01I±12

A09286AB0117
A09271
LOCK
BATT
(±) (+)
A00356
Engine Room J/B No.2
EFI Fuse
± DIAGNOSTICSENGINE
DI±111
1 Check voltage between terminal BATT of ECM connector and body ground.
PREPARATION:
Remove the glove compartment (See Pub. No. RM654U, page
SF±64).
CHECK:
Measure the voltage between terminal BATT of the ECM con-
nector and body ground.
OK:
Voltage 9 ± 14 V
OK Check and replace ECM (See page IN±29).
NG
2 Check EFI fuse.
PREPARATION:
Remove the EFI fuse from the engine room J/B No.2.
CHECK:
Check the continuity of the 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±29).