Page 465 of 1767

Diagnostic Procedure
1 CHECK VEHICLE SPEED SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector and combination meter harness connector.
3. Check harness continuity between ECM terminal 26 and combination meter terminal 26. Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 2.
NGERepair open circuit or short to ground or short to power in harness or connectors.
2 CHECK SPEEDOMETER FUNCTION
Make sure that speedometer functions properly.
OK or NG
OKEGO TO 4.
NGEGO TO 3.
3 CHECK SPEEDOMETER CIRCUIT FOR OPEN AND SHORT
Check the following.
IHarness connectors F108, E225
IHarness connectors M842, F135 (RHD models)
IHarness for open or short between combination meter and vehicle speed sensor
OK or NG
OKECheck vehicle speed sensor and combination meter. Refer to EL section.
NGERepair open circuit or short to ground or short to power in harness or connectors.
4 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-78.
EINSPECTION END
DTC 0104 VEHICLE SPEED SENZD30DDTi
EC-103
Page 466 of 1767

Description
The accelerator switch is installed to the accelerator pedal assem-
bly. The switch senses accelerator position and sends an ON-OFF
signal to the ECM. The ECM uses the signal to control the fuel cut
operation at deceleration for better fuel efficiency.
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SW (FC)IIgnition switch: ON
(Engine stopped)Accelerator pedal: fully released CLOSE
Accelerator pedal: slightly open OPEN
DECELER F/CUTIEngine: After warming up Idle OFF
ECM Terminals and Reference Value
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may damage the
ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
29 LG/R Accelerator switch (F/C)Ignition switch ªONº
Accelerator pedal fully releasedBATTERY VOLTAGE
(11 - 14V)
Ignition switch ªONº
Accelerator pedal depressedApproximately 0V
On Board Diagnosis Logic
Malfunction is detected when .... Check Items (Possible Cause)
IThe OFF signal (short) is sent to the ECM for a certain period
of time even when the accelerator pedal is not being
depressed.IHarness or connectors
(The switch circuit is shorted.)
IAccelerator switch (F/C)
MEC986D
DTC 0203 ACCEL POS SW (F/C)ZD30DDTi
EC-104
Page 467 of 1767
DTC Confirmation Procedure
WITH CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Fully depress and fully release accelerator pedal, and wait 15
seconds.
4) Repeat step 3 at least 29 times.
5) If DTC is detected, go to ªDiagnostic Procedureº, EC-107.
WITHOUT CONSULT-II
1) Turn ignition switch ªONº.
2) Fully depress and fully release accelerator pedal, and then wait
15 seconds.
3) Repeat step 2 at least 29 times.
4) Turn ignition switch ªOFFº, wait at least 5 seconds and then turn
ªONº.
5) Perform ªDiagnostic Test Mode II (Self-diagnostic results)º with
ECM.
6) If DTC is detected, go to ªDiagnostic Procedureº, EC-107.SEF817Y
DTC 0203 ACCEL POS SW (F/C)ZD30DDTi
EC-105
Page 468 of 1767
Wiring Diagram
YEC178A
DTC 0203 ACCEL POS SW (F/C)ZD30DDTi
EC-106
Page 469 of 1767

Diagnostic Procedure
1 CHECK ACCELERATOR SWITCH (F/C) GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
3. Disconnect accelerator switch (F/C) harness connector.
MEC995D
4. Check harness continuity between accelerator switch (F/C) terminal 3 and engine ground. Refer to Wiring Diagram.
Continuity should exist.
5. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 3.
NGEGO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors F108, E225
IHarness connectors M842, F135 (RHD models)
IHarness for open or short between accelerator switch (F/C) and engine ground
ERepair open circuit or short to ground or short to power in harness or connectors.
3 CHECK ACCELERATOR SWITCH (F/C) INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 29 and accelerator switch (F/C) terminal 1. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 4.
NGERepair open circuit or short to ground or short to power in harness or connectors.
DTC 0203 ACCEL POS SW (F/C)ZD30DDTi
EC-107
Page 470 of 1767
4 CHECK ACCELERATOR SWITCH (F/C)
1. Disconnect accelerator switch harness connector.
2. Check continuity between accelerator switch (F/C) connector terminals 1 and 3 under the following conditions.
MEC997D
MTBL1323
OK or NG
OKEGO TO 5.
NGEReplace accelerator pedal assembly.
5 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-78.
EINSPECTION END
DTC 0203 ACCEL POS SW (F/C)ZD30DDTi
Diagnostic Procedure (Cont'd)
EC-108
Page 471 of 1767
Description
SYSTEM DESCRIPTION
Sensor Input signal to ECM ECM function Actuator
Vehicle speed sensor Vehicle speed
Cooling fan con-
trolCooling fan relay Engine coolant temperature sensor Engine coolant temperature
Air conditioner switch Air conditioner ªONº signal
The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, air condi-
tioner ON signal. The control system has 2-step control [ON/OFF].
OPERATION
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
AIR COND SIGIEngine: After warming up, idle the
engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
COOLING FANIWhen cooling fan is stopped. OFF
IWhen cooling fan operates. ON
SEF450Z
DTC 0208 OVER HEATZD30DDTi
EC-109
Page 472 of 1767

ECM Terminals and Reference Value
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may damage the
ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
14 LG/R Cooling fan relayEngine is running.
Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
Engine is running.
Cooling fan is operatingApproximately 0.1V
On Board Diagnosis Logic
This diagnosis continuously monitors the engine coolant temperature.
If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
Malfunction is detected when ... Check Items (Possible Cause)
ICooling fan does not operate properly (Overheat).
ICooling fan system does not operate properly (Overheat).
IEngine coolant was not added to the system using the proper
filling method.IHarness or connectors
(The cooling fan circuit is open or shorted.)
ICooling fan
IRadiator hose
IRadiator
IRadiator cap
IWater pump
IThermostat
IFan belt
IEngine coolant temperature sensor
For more information, refer to ªMAIN 12 CAUSES OF
OVERHEATINGº, EC-120.
CAUTION:
When a malfunction is indicated, be sure to replace the coolant following the procedure in the MA
section (ªChanging Engine Coolantº, ªENGINE MAINTENANCEº). Also, replace the engine oil.
1) Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to MA section (ªAnti-freeze Coolant Mixture Ratioº,
ªRECOMMENDED LUBRICANTS AND FLUIDSº).
2) After refilling coolant, run engine to ensure that no water-flow noise is emitted.
DTC 0208 OVER HEATZD30DDTi
EC-110