2001 TOYOTA AVALON Service Repair Manual

F09479
IGAGND
Lean to LeftLean to Right GL1
Front
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-257
413 Author
: Date
:
2001 AVALON (RM808U)
HINT:
If the off center angle is greater than 3 degrees from center, fur-
ther adjustments to the tie rods may be necessary.
(d) Shift the gear selector switch to the P range.
(e) Press the VSC OFF switch and hold it while depressing
the brake pedal 3 times within 2 seconds.
(f) Continue to hold the VSC OFF switch until the VSC buzz-
er (repeated beeping) sounds.
(g) Release the VSC OFF switch. The VSC buzzer will con-
tinue to sound for 3 seconds confirming the operation is
complete.
HINT:
If the procedure is done correctly and VSC buzzer does not
sound, there may be a malfunction of the steering angle sensor.
4. DECELERATION SENSOR CHECK
(a) Apply battery positive voltage.
(b) Connect IGA terminal to the battery positive (+) terminal,
and GND terminal to the battery negative (-) terminal, and
apply about 12 V between IGA and GND terminals.
(c) Check the output voltage of GL1 terminal.
SymbolsConditionStandard Value
GL1HorizontalAbout 2.5 V
GL1Lean right downAbout 2.3 V - 4V
GL1Lean left down1 V - About 2.3 V
HINT:

If the sensor is tilted too much, it may show the wrong val-
ue.

If dropped, the sensor should be replaced with a new one.

The sensor removed from the vehicle should not be
placed upside down.

DI6NW-01
DI-266
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
422 Author
: Date
:
2001 AVALON (RM808U)
PROBLEM SYMPTOMS TABLE
If a normal code is displayed during the DTC check but the problem still occurs, check the circuits for each
problem symptom in the order given in the table below and proceed to the relevant troubleshooting page.
NOTICE:
When replacing ABS & BA & TRAC & VSC ECU, sensor, etc., turn the IG switch OFF.
SymptomSuspect AreaSee page
ABS does not operate
Only when 1. - 4. are all normal and the problem is still
occurring, replace the ABS & BA & TRAC & VSC ECU.
4. Check the DTC, reconfirming that the normal code is
output.
5. IG power source circuit
6. Speed sensor circuit
7. Check the brake actuator with a hand-held tester.
If abnormal, check the hydraulic circuit for leakage
(See page DI-346).
DI-252
DI-297
DI-267
BR-52
ABS does not operate efficiently
Only when 1. - 4. are all normal and the problem is still
occurring, replace the ABS & BA & TRAC & VSC ECU.
1. Check the DTC, reconfirming that the normal code is
output.
2. Speed sensor circuit
3. Stop light switch circuit
4. Check the brake actuator with a hand-held tester.
If abnormal, check the hydraulic circuit for leakage
(See page DI-346).
DI-252
DI-267
DI-303
BR-52
ABS warning light abnormal1. ABS warning light circuit
2. ABS & BA & TRAC & VSC ECUDI-325
DTC check cannot be done
Only when 1. - 4. are all normal and the problem is still
occurring, replace the ABS & BA & TRAC & VSC ECU.
1. ABS warning light circuit
2. VSC warning light circuit
3. Tc terminal circuit
DI-325
DI-327
DI-342
Speed sensor signal check cannot be done1. Ts terminal circuit
2. ABS & BA & TRAC & VSC ECUDI-344
VSC does not operate
Only when circuits inspected for each problem symptom
are all normal and the problem is still occurring, replace the
ABS & BA & TRAC & VSC ECU.
1. Check the DTC, reconfirming that the normal code is
output.
2. IG power source circuit
3. Hydraulic circuit for leakage
4. Speed sensor circuit
DI-252
DI-297
DI-346
DI-267
BA does not operateStop light switch circuitDI-303
SLIP indicator light abnormalSLIP indicator light circuitDI-333
BRAKE warning light abnormal1. BRAKE warning light circuit
2. ABS & BA & TRAC & VSC ECUDI-330
VSC OFF indicator light abnormal
Only when circuits inspected for each problem symptom
are all normal and the problem is still occurring, replace the
ABS & BA & TRAC & VSC ECU.
1. VSC OFF indicator light circuit
2. VSC OFF switch circuit
DI-336
DI-336

DI6NV-03
F07884
A20
DI-262
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
418 Author
: Date
:
2001 AVALON (RM808U)
TERMINALS OF ECU
ABS & BA & TRAC & VSC ECU:
Symbols (Terminals No.)Wiring ColorConditionSTD Voltage (V)
IG1 (A20 - 1) - GND (A20 -
28, 29)Y-R e W-BIG switch ON10 - 14
R+ (A20 - 2) - SR (A20 - 36)GR-R e RIG switch ON, ABS warning light OFF10 - 14
R+ (A20 - 2) - MR (A20 - 7)GR-R e GR-LIG switch ONBelow 1.0
SFLR (A20 - 3) - GND (A20 -
28, 29)G-O e W-BIG switch ON, ABS warning light OFF10 - 14
SRRR (A20 - 4) - GND (A20 -
28, 29)G-R e W-BIG switch ON, ABS warning light OFF10 - 14
SFLH (A20 - 5) - GND (A20 -
28, 29)W-R e W-BIG switch ON, ABS warning light OFF10 - 14
SRRH (A20 - 6) - GND (A20 -
28, 29)GR e W-BIG switch ON, ABS warning light OFF10 - 14
FL+ (A20 - 8) - FL- (A20 - 10)BR e B-RIG switch ON, slowly turn left front wheelAC generation
RR+ (A20 - 11) - RR- (A20 -
12)G e YIG switch ON, slowly turn right rear wheelAC generation
RL+ (A20 - 13) - RL- (A20 -
14)LG e VIG switch ON, slowly turn left rear wheelAC generation
FR+ (A20 - 17) - FR- (A20 -
16)B-W e LIG switch ON, slowly turn right front wheelAC generation
GL1 (A20 - 18) - GND (A20 -
28, 29)G e W-BIG switch ON0.5 - 4.5
ML+ (A20 - 22) - ML- (A20 -
24)W-R e VIG switch ON10 - 14
SRLR (A20 - 25) - GND (A20 -
28, 29)L-Y e W-BIG switch ON, ABS warning light OFF10 - 14
SFRH (A20 - 26) - GND (A20
- 28, 29)B-W e W-BIG switch ON, ABS warning light OFF10 - 14
MT (A20 - 27) - GND (A20 -
28, 29)O e W-BIG switch ON, ABS warning light OFFBelow 1.5
IND (A20 - 31) - GND (A20 -VWBIG switch ON, SLIP indicator light ONBelow 2.0IND (A20 31) GND (A20
28, 29)V e W-BIG switch ON, SLIP indicator light OFF10 - 14
EBDW (A20 - 32) - GND (A20RYWBIG switch ON, BRAKE warning light OFFBelow 1.5EBDW (A20 32) GND (A20
- 28, 29)R-Y e W-BIG switch ON, BRAKE warning light ON10 - 14
LBL (A20 - 40) - GND (A20 -
28, 29)L-B e W-BIG switch ON, fluid level switch ONBelow 1.0

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-263
419 Author
: Date
:
2001 AVALON (RM808U) Ts (A20 - 42) - GND (A20 - 28,
29)
LG-B e W-BIG switch ON10 - 14
CSW (A20 - 44) - GND (A20 -WLWBIG switch ON, VSC OFF indicator ONBelow 1.5CSW (A20 44) GND (A20
28, 29)W-L e W-BIG switch ON, VSC OFF indicator OFF8 - 14
D/G (A20 - 46) - GND (A20 -
28, 29)W e W-BIG switch ON10 - 14
STP (A20 - 48) - GND (A20 -GWWBStop light switch ON (Brake pedal pushed)8 - 14STP (A20 48) GND (A20
28, 29)G-W e W-BStop light switch OFF (Brake pedal released)Below 1.5
SMC1 (A20 - 49) - GND (A20
- 28, 29)G-Y e W-BIG switch ON, ABS warning light OFF10 - 14
SMC2 (A20 - 50) - GND (A20
- 28, 29)V-W e W-BIG switch ON, ABS warning light OFF10 - 14
BAT (A20 - 51) - GND (A20 -
28, 29)W-L e W-BIG switch OFF10 - 14
SRC2 (A20 - 52) - GND (A20 -
28, 29)R-B e W-BIG switch ON, ABS warning light OFF10 - 14
SRLH (A20 - 53) - GND (A20 -
28, 29)Y-B e W-BIG switch ON, ABS warning light OFF10 - 14
SRC1 (A20 - 54) - GND (A20 -
28, 29)B-Y e W-BIG switch ON, ABS warning light OFF10 - 14
SFRR (A20 - 55) - GND (A20
- 28, 29)W-G e W-BIG switch ON, ABS warning light OFF10 - 14
SS1 (A20 - 59) - GND (A20 -
28, 29)W e W-BIG switch ONPulse generation
FSS (A20 - 60) - GND (A20 -
28, 29)BR e W-BIG switch OFFContinuity
SS2 (A20 - 61) - GND (A20 -
28, 29)O e W-BIG switch ONPulse generation
VCM (A20 - 65) - GND (A20 -
28, 29)P-L e W-BIG switch ON4.5 - 5.5
PMC (A20 - 66) - GND (A20 -
28, 29)R-L e W-BIG switch ON, brake pedal released0.3 - 0.8
E2 (A20 - 67) - GND (A20 -
28, 29)BR-Y e W-BIG switch OFFContinuity
SP1 (A20 - 68) - GND (A20 -
28, 29)L-O e W-BVehicle driveing at about 20 km/h (12 mph)Pulse generation
WT (A20 - 69) - GND (A20 -YRWBIG switch ON, VSC OFF indicator light ONBelow 2.0WT (A20 69) GND (A20
28, 29)Y-R e W-BIG switch ON, VSC OFF indicator light OFF10 - 14
VSCW (A20 - 70) - GND (A20PBWBIG switch ON, VSC warning light ONBelow 2.0VSCW (A20 70) GND (A20
- 28, 29)P-B e W-BIG switch ON, VSC warning light OFF10 - 14
PKB (A20 - 74) - GND (A20 -YGWBIG switch ON, parking brake switch ONBelow 2.0PKB (A20 74) GND (A20
28, 29)Y-G e W-BIG switch ON, parking brake switch OFF10 - 14
YD (A20 - 75) - GND (A20 -
28, 29)BR e W-BIG switch ON, VSC warning light OFF4.5 - 5.5
GYAW (A20 - 76) - GND (A20
- 28, 29)Y e W-BIG switch OFFContinuity
YAW (A20 - 77) - GND (A20 -
28, 29)L e W-BIG switch ON, vehicle stationaly condition2 - 3

DI-264
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
420 Author
: Date
:
2001 AVALON (RM808U) WA (A20 - 81) - GND (A20 -
BWBIG switch ON, ABS warning light ON10 - 14WA (A20 81) GND (A20
28, 29)B e W-BIG switch ON, ABS warning light OFFBelow 2.0
Tc (A20 - 84) - GND (A20 - 28,
29)LG-R e W-BIG switch ON10 - 14
Bz (A20 - 86) - GND (A20 -LWWBIG switch ON, VSC buzzer soundsBelow 1.0 e10 - 14Bz (A20 86) GND (A20
28, 29)L-W e W-BIG switch ON, VSC buzzer does not sound10 - 14

F07885
1 2 3 4 5 6 7 8 9 10
11 12 13
14
21 22 23 24 25 26
15
16 17 18 19 20
T5
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-265
421 Author
: Date
:
2001 AVALON (RM808U)
Translate ECU:
Symbols (Terminals No.)Wiring ColorConditionSTD Voltage (V)
IG1(T5 - 1) - GND (T5 - 14)Y-R e W-BIG switch ON10 - 14
PKB2 (T5 - 2) - GND (T5 -YGWBIG switch ON, paking brake switch ONBelow 2.0PKB2 (T5 2) GND (T5
14)Y-G e W-BIG switch ON, paking brake switch OFF10 - 14
VSC+ (T5 - 4) - VSC- (T5 -
17)W e OEngine idlingPulse generation
SS1 (T5 - 5) - SS2 (T5 - 18)L e B-WEngine idlingPulse generation
RSS (T5 - 6) - GND (T5 - 14)BR e W-BIG switch OFFContinuity
P (T5 10) GND (T5 14)GWWBIG switch ON, shift lever is in P range8 - 14P (T5 - 10) - GND (T5 - 14)G-W e W-BIG switch ON, shift lever is in other than P rangeBelow 1.5
LVL2 (T5 - 11) - GND (T5 - 14)R-W e W-BIG switch ON, fluid level switch ONBelow 1.5
D (T5 12) GND (T5 14)YRWBIG switch ON, shift lever is in D range8 - 14D (T5 - 12) - GND (T5 - 14)Y-R e W-BIG switch ON, shift lever is in other than D rangeBelow 1.5
NEO (T5 - 13) - GND (T5 - 14)Y-B e W-BEngine idlingPulse generation
PKB (T5 - 15) - GND (T5 - 14)Y-G e W-BIG switch OFF, parking brake switch ONBelow 2.0
BRL (T5 16) GND (T5 14)RWWBIG switch ON, BRAKE warning light ONBelow 2.0BRL (T5 - 16) - GND (T5 - 14)R-W e W-BIG switch ON, BRAKE warning light OFF10 - 14
TRC+ (T5 - 20) - TRC- (T5 -
7)BR e W-BEngine idlingPulse generation
Tc (T5 - 21) - GND (T5 - 14)LG-R e W-BIG switch ON10 - 14
ENG+ (T5 - 22) - ENG- (T5 -
9)V e GREngine idlingPulse generation
Ts (T5 - 24) - GND (T5 - 14)LG-B e W-BIG switch ON10 - 14
LBL (T5 - 25) - GND (T5 - 14)L-B e W-BIG switch ON, fluid level switch ONBelow 1.0
CCS (T5 - 26) - GND (T5 - 14)Y-R e W-BIG switch ONBelow 2.0

D07905
C15 E7 Cruise Control ECU
14
ODGR24
OD1ECM
- DIAGNOSTICSAUTOMATIC TRANSAXLE
DI-203
359 Author
: Date
:
2001 AVALON (RM808U)
O/D Cancel Signal Circuit
CIRCUIT DESCRIPTION
While driving uphill with cruise control activated, in order to minimize gear shifting and provide smooth cruis-
ing overdrive may be prohibited temporarily under some condition.
The cruise control ECU sends O/D cut signals to the ECM as necessary and the ECM cancels overdrive
shifting until these signals are discontinued.
WIRING DIAGRAM
DI02S-08

BE3840D00835D07206
ON
(-) (+)
OD1
AB0119
N19917
I00742
ON
O/D
(-)
(+)
DI-204
- DIAGNOSTICSAUTOMATIC TRANSAXLE
360 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check voltage between terminal OD1 of ECM and body ground.
PREPARATION:
(a) Remove the glove compartment.
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between terminal OD1 of ECM and body
ground.
OK:
Voltage: 10 - 14 V
OK Proceed to next circuit inspection shown on
problem symptoms table (See page DI-175).
NG
2 Check voltage between terminal OD of cruise control ECU harness side connec-
tor and body ground.
PREPARATION:
(a) Disconnect the cruise control ECU connector.
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between terminal OD of cruise control ECU
harness side connector and body ground.
OK:
Voltage: 10 - 14 V
OK Check and replace the cruise control ECU
(See page IN-30).
NG