I00292
Vehicle Speed Sensor
ECU
Combination Meter
Cruise Control ECU
4 pulses/
1 rotation
of rotor shaft
4 pulses/
1 rotation
of rotor shaft
I21977
C17
Cruise Control ECU
12
Combination Meter
3
C10
G–O
G–R
GAUGE
FUSE
C10
3
IK2
V10
Vehicle Speed Sensor
(Combination Meter)
1
B–R*1
2
8
SPD
J/B No. 3
L
5
3D
C10
6
20
IK2
3
2
G–R
L
3D
G–O
P*2
*1: Expect 5VZ–FE
*2: 5VZ–FE
DI–738
–
DIAGNOSTICS
CRUISE CONTROL SYSTEM (w/o ETCS–i)
1000
Author:
Date:
2003 TOYOTA TACOMA (RM1002U)
DTC
21
Open in Vehicle Speed Sensor Circuit
CIRCUIT DESCRIPTION
Vehicle speed sensor circuit sends a signal to the cruise control ECU as a vehicle speed signal.
The rotor shaft is driven by the gear of the transmission.
For each rotation of the shaft, the vehicle speed sensor sends a 4–pulse signal through the combination
meter to the cruise control ECU (See the following illustration).
This signal is converted inside the combination meter and sent as a 4–pulse signal to the cruise control ECU.
The ECU calculates the vehicle speed from this pulse frequency.
DTC No.
DTC Detection Condition
Trouble Area
21
Speed signal is not input to the cruise control ECU while cruise
control is set
Combination meter
Harness or connector between cruise control ECU and com-
bination meter, and combination meter and vehicle speed
sensor
Vehicle speed sensor
Cruise control ECU
WIRING DIAGRAM
DI8ZH–04
Input Signal
Indicator Light
Blinking Pattern
Drive at about
40 km/h (25 mph)
or below
Drive at about
40 km/h (25 mph)
or higher
Light ON
OFF
Light
ON
OFF
–
DIAGNOSTICS
CRUISE CONTROL SYSTEM (w/o ETCS–i)
DI–739
1001
Author:
Date:
2003 TOYOTA TACOMA (RM1002U)
INSPECTION PROCEDURE
1
Input signal check.
CHECK:
(a)
See the input signal check on page DI–721.
(b)
Check the indicator light operation when driving with ve-
hicle speed of above 40 km/h (25 mph), and with vehicle
speed of below 40 km/h (25 mph).
OK:
Vehicle speed above 40 km/h (25 mph):
Indicator light blinks
Vehicle speed below 40 km/h (25 mph):