FUEL SYSTEM <4D5-step
III
> - Troubleshooting
13-16
Code No. 21 Crank angle sensor system
Probable cause
Range of Check
D
Engine cranking
Set Conditions
D
Sensor output voltage does not change for 2 seconds (no pulse signal input)
D
Malfunction of crank angle sensor
D
Open circuit or short-circuit in crank angle sensor
circuit, or poor connector contact
D
Engine-ECU inoperative
Range of Check
D
Ignition switch: ON
D
Not during the engine cranking
D
Pump speed sensor circuit: Normal
Set Conditions
D
When crank angle sensor signal is being input normally, suddenly no sensor
signal is input for 0.3 seconds or more
OK
Check the harness between the
crank angle sensor and the engine
control relay, and repair if necessary.
OK
OK
NG
Repair
(1) NG
Measure at crank angle sensor
connector A-112
D
Connect the connector.
(Test harness: MB998478 used)
D
Voltage between 2 (black clip)
and the earth
OK:
0.4 - 4.0 V
(Engine: cranking)
1.5 - 2.5 V
(Engine: idling)
NG
Replace the crank angle sensor.
Replace the engine-ECU.
Check the following connector:
C-126
NG
NG
Check the trouble symptoms.
OK
Repair
Check the following connector:
C-43
NG
OK
Repair
NG
Check the harness between the
engine-ECU and the crank angle
sensor.
NG
Check the trouble symptoms.
Replace the engine-ECU.
Check the harness between the
crank angle sensor and the earth,
and repair if necessary.
OK
Repair
NG
Check the following connector:
A-112
Check the trouble symptoms.
Measure at crank angle sensor
connector A-112.
D
Disconnect the connector and
measure at the harness side.
(1) Voltage between 3 and the earth
(Ignition switch: ON)
OK:
System voltage
(2) Continuity between 2 and the
earth (Ignition switch: ON)
OK:
4.6 - 5.4 V
(3) Continuity between 1 and the
earth
OK:
Continuity
(2) NG
(3) NG