2005 TOYOTA AVENSIS diagnostic

A81013
ECM
+BMREL IGSW J27
9
B−W I13
Ignition Switch
6IGNB−W E
E1
EE110BR
W−B 1Driver Side J/B
2 2
1E9
E9
E98
1
7
E12 J26A
B−W
C C B−W
J8
J/C DA 18
DH2
4
EFI5
1
32 EFI
MAIN
Relay
B−W Engine Room R/B No. 1IK1
6J/C
IE12
BR B−R
Battery AM2B−W
EC
EI
AM2 IG2
GR
B B
33
Engine Room R/B No. 3
FL MAIN1 1
1 1A1 1
1 1 B−R B−R
IE4 1(LHD)
IP1 1(RHD)B−W (RHD) (RHD)
(LHD)
(LHD)
GR B−Y (RHD) B−R (LHD)
− DIAGNOSTICSECD SYSTEM (1CD−FTV)(From September, 2003)
05−489
AVENSIS Supplement (RM1045E)
ECM POWER SOURCE CIRCUIT
CIRCUIT DESCRIPTION
When the ignition switch is turned to ON, the positive battery voltage is applied to terminal IGSW of the ECM
and the EFI MAIN relay control circuit in the ECM sends a signal to terminal MREL of the ECM switching
on the EFI MAIN relay.
This signal causes current to flow to the coil, closing the contacts of the EFI MAIN relay and supplying power
to terminal +B of the ECM.
WIRING DIAGRAM
05B5V−05

A18294
E1 (−)+B (+)
ECM Connecter
E12E9
A65745
E12
ECM Connector
E1
A18294
E1 (
−)IGSW (+)
ECM Connecter
E9
E12
05 −490
−
DIAGNOSTICS ECD SYSTEM (1CD−FTV)(From September, 2003)
AVENSIS Supplement (RM1045E)
INSPECTION PROCEDURE
1 INSPECT ECM(+B VOLTAGE)
(a) Turn the ignition switch to ON.
(b) Measure the voltage between the specified terminals of
the E9 and E12 ECM connectors.
Standard:
Tester ConnectionSpecified Condition
+B (E9 −1) − E1 (E12 −7)9to 14V
OK PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN PROBLEM SYMPTOMS TABLE
(See page 05 −282)
NG
2 CHECK HARNESS AND CONNECTOR(ECM −BODY GROUND)
(a) Disconnect the E12 ECM connector.
(b) Check the resistance between the wire harness side con-
nectors.
Standard (Check for open):
Tester ConnectionSpecified Condition
E1 (E12 −7) −Body groundBelow 1

(c) Reconnect the ECM connector.
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
3 INSPECT ECM(IGSW VOLTAGE)
(a) Turn the ignition switch to ON.
(b) Measure the voltage between the specified terminals of the E9 and E12 ECM connectors.
Standard:
Tester ConnectionSpecified Condition
IGSW (E9 −9) −E1 (E12 −7)9to14V
OK Go to step 6
NG

A79096
Driver Side J/B:IGN Fuse
B50489Ignition Switch
I13
Component Side:
A18294
E1 (
−)MREL (+)
ECM Connecter
E12E9
−
DIAGNOSTICS ECD SYSTEM (1CD−FTV)(From September, 2003)
05 −49 1
AVENSIS Supplement (RM1045E)
4 INSPECT FUSE(IGN FUSE)
(a) Remove the IGN fuse from the driver side J/B.
(b) Check for continuity in the IGN fuse.
Standard: Continuity
(c) Reinstall the IG2 fuse.
NG CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE
OK
5 INSPECT IGNITION OR STARTER SWITCH ASSY
(a) Disconnect the I13 ignition switch connector.
(b) Check for continuity between the connector terminals shown in the chart below.
Standard:
SwitchTester ConnectionSpecified Condition
LOCKAll TerminalsNo continuity
ACC1− 3Continuity
ON1− 2, 1 −3, 2 −3, 5 −6Continuity
START4− 5, 4 −6, 5 −6, 1 −2Continuity
(c) Reconnect the ignition switch connector.
NG REPLACE IGNITION OR STARTER SWITCH ASSY
OK
CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY − IGNITION SWITCH, IGNITION
SWITCH − ECM)
6 INSPECT ECM(MREL VOLTAGE)
(a) Turn the ignition switch to ON.
(b) Measure the voltage between the specified terminals of
the E9 and E12 ECM connectors.
Standard:
Tester ConnectionSpecified Condition
MREL (E9 −8) −E1 (E12 −7)9to14V
NG REPLACE ECM (See page 10− 29)
OK

A82884
Engine Room R/B No.1:
EFI Fuse
B16200
05−492
− DIAGNOSTICSECD SYSTEM (1CD−FTV)(From September, 2003)
AVENSIS Supplement (RM1045E)
7 INSPECT FUSE(EFI FUSE)
(a) Remove the EFI fuse from the engine room R/B No. 1.
(b) Check for continuity in the EFI fuse.
Standard: Continuity
(c) Reinstall the EFI fuse.
NG CHECK FOR SHORT IN ALL HARNESSES AND
COMPONENTS CONNECTED TO FUSE
OK
8 INSPECT EFI MAIN RELAY
(a) Remove the EFI MAIN relay from the engine room R/B
No. 1.
(b) Check for continuity in the EFI MAIN relay.
Standard:
Tester ConnectionSpecified Condition
1−2Continuity
No continuity
3−5Continuity
(Apply battery voltage to terminals 1 and 2)
(c) Reinstall the EFI MAIN relay.
NG REPLACE EFI MAIN RELAY
OK

A66056
Engine Room R/B No.1:
EFI MAIN Relay
A65748
MREL
E9
ECM Connector
− DIAGNOSTICSECD SYSTEM (1CD−FTV)(From September, 2003)
05−493
AVENSIS Supplement (RM1045E)
9 CHECK HARNESS AND CONNECTOR(EFI MAIN RELAY−ECM, EFI MAIN RELAY
−BODY GROUND)
(a) Check the harness and connector between the EFI MAIN
relay and ECM.
(1) Remove the EFI MAIN relay from the engine room
R/B No. 1.
(2) Disconnect the E9 ECM connector.
(3) Check the resistance between the wire harness
side connectors.
Standard (Check for open):
Tester ConnectionSpecified Condition
EFI MAIN relay (1)−MREL (E9−8)Below 1

Standard (Check for short):
Tester ConnectionSpecified Condition
EFI MAIN relay (1) or MREL (E9−8)−Body ground10 k
or higher
(4) Reinstall the EFI MAIN relay.
(5) Reconnect the ECM connector.
(b) Check the harness and connector between the EFI MAIN
relay and body ground.
(1) Remove the EFI MAIN relay from the engine room
R/B No. 1.
(2) Check the resistance between the wire harness
side connector and body ground.
Standard (Check for open):
Tester ConnectionSpecified Condition
EFI MAIN relay (2)−Body groundBelow 1

(3) Reinstall the EFI MAIN relay.
OK REPAIR OR REPLACE HARNESS OR
CONNECTOR
NG
CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF ECM−BATTERY POS-
ITIVE TERMINAL)

05−484
−
DIAGNOSTICS ECD SYSTEM (1CD −FTV)(From September, 2003)
AVENSIS Supplement (RM 1045E)
DTC P2237 OXYGEN (A/F) SENSOR PUMPING
CURRENT CIRCUIT/OPEN (FOR A/F
SENSOR)(BANK1 SENSOR 1)
DTC P2238 OXYGEN (A/F)SENSOR PUMPING CURRENT CIRCUIT LOW (FOR A/F SENSOR)(BANK 1
SENSOR 1)
DTC P2239 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT HIGH (FOR A/F
SENSOR)(BANK1 SENSOR 1)
HINT:
S For more information on the A/F sensor and TOYOTA D −CAT (* 1) system, see page 05 −255.
S If P2237, P2238 and/or P2239 is present, refer to the diagnostic trouble codes (DTCs) table for TOYO-
TA D −CAT system on page 05 −255.
S These DTCs are recorded when A/F sensor has malfunction, although the caption is the oxygen sen-
sor.
* 1 : Diesel Clean Advanced Technology.
CIRCUIT DESCRIPTION
Refer to DTC P003 1 on page 05 −305.
DTC No.DTC Detecting ConditionTrouble Area
P2237ECM internal error ( 10 seconds)
( 1 trip detection logic)S ECM
P2238
S A/F sensor circuit low (bank 1 sensor 1)
AF+ is less than 04 V for 50 seconds or more
Main trouble area: Open in A/F sensor circuit
S Open or short in A/F sensor circuit
S A/F sensor
S A/F sensor heaterP2238AF+ is less than 0.4 V for 5.0 seconds or more
( 1 trip detection logic)S A/F sensor heater
S A/F sensor heater relay
S A/F sensor heater and relay circuit
S ECM
P2239
S A/F sensor circuit high (bank 1 sensor 1)
AF+ is more than 44 V for 50 seconds or more
Main trouble area: Short in A/F sensor circuit
S Open or short in A/F sensor circuit
S A/F sensor
S A/F sensor heaterP2239AF+ is more than 4.4 V for 5.0 seconds or more
( 1 trip detection logic)S A/F sensor heater
S A/F sensor heater relay
S A/F sensor heater and relay circuit
S ECM
MONITOR DESCRIPTION
The A/F sensor has a characteristic that it varies its voltage output in proportion to the air −fuel ratio. If imped-
ance (alternating current resistance) or voltage output of the sensor extraordinarily deviates from the stan-
dard range, the ECM interprets this as an open or short malfunction of the A/F sensor circuit.
WIRING DIAGRAM
Refer to DTC P003 1 on page 05 −305.
05I7U −01

A87894
AF− AF+
A34
Front View
Component Side
(w/ Headlight Beam Level Control):
1
2
3
4
HT
+B
A/F Sensor
Connector
A87894
AF−
AF+
A34
Front View
HT +B
1
2
3
4
Component Side
(w/o Headlight Beam Level Control):
A/F Sensor
Connector
−
DIAGNOSTICS ECD SYSTEM (1CD −FTV)(From September, 2003)
05 −485
AVENSIS Supplement (RM 1045E)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand−held tester. Freeze frame data records the engine conditions when
a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was
running or stopped, if the engine was warmed up or not, if the air −fuel ratio was lean or rich, and other data
from the time the malfunction occurred.
1 CHECK OTHER DTC(IN ADDITION TO P2237)
(a) Connect the hand −held tester to the DLC3.
(b) Turn the ignition switch to ON and turn the hand −held tester ON.
(c) Select the item ”DIAGNOSIS / OBD/MOBD / DTC INFO / CURRENT CODES”.
(d) Read DTCs.
Result:
Display (DTC output)Proceed to
P2237 and P2238 and/or P2239A
P2237B
B REPLACE ECM (See page 10− 29)
A
2 INSPECT AIR FUEL RATIO SENSOR(RESISTANCE)
(a) Disconnect the A34 A/F sensor connector.
(b) Measure the resistance between the terminals of the A/F sensor.
Resistance (w/ Headlight beam level control):
Tester ConnectionSpecified Condition
HT (1) − +B (2)0.86 to 1.1
at 20 _C (68 _F)
Resistance (w/o Headlight beam level control):
Tester ConnectionSpecified Condition
HT (2) −+B ( 1)0.86 to 1.1
at 20 _C (68 _F)
(c) Reconnect the A/F sensor connector.
NG REPLACE AIR FUEL RATIO SENSOR
OK

B16200
05−486
− DIAGNOSTICSECD SYSTEM (1CD−FTV)(From September, 2003)
AVENSIS Supplement (RM1045E)
3 INSPECT AIR FUEL RATIO SENSOR HEATER RELAY
(a) Remove the A/F sensor heater relay.
(b) Check for continuity in the A/F sensor heater relay.
Standard:
Tester ConnectionSpecified Condition
1−2Continuity
No continuity
3−5Continuity
(Apply battery voltage to terminals1and 2)
(c) Reinstall the A/F sensor heater relay.
NG REPLACE AIR FUEL RATIO SENSOR HEATER
RELAY
OK