M161 ENGINE CONTROLS 1F2 -- 39
D AEW OO M Y_2000
IGNITION SWITCH
KAB1F200
Failure
CodeDescriptionTrouble AreaMaintenance Hint
71Starter signal
recognition failureWhen not detection of starter
signal
DInspection the Engine Control Module
(ECM) pin 2 circuit short or open with
bad contact
DInspection ECM
M161 ENGINE CONTROLS 1F2 -- 43
D AEW OO M Y_2000
KAB1F210
Failure
CodeDescriptionTrouble AreaMaintenance Hint
34Fuel pump relay short
circuit to batteryWhen short circuit to power
sourceDInspection the Engine Control Module
(ECM) pin 33 about short circuit or
openwithbadcontact
35Fuel pump relay short
circuit to ground or openWhen short circuit to ground
or open
openwithbadcontact
DInspection the fuel pump relay
DInspection the ECM
Circuit Description
When the ignition switch is turned ON, the ECM will activate the pump relay and run the in -- tank fuel pump. The fuel
pump willoperate as long as the engine is cranking or running and the ECM is receiving ignition reference pulses.
If there are no reference pulses, the ECM will shut off the fuel pump within 2 seconds after the ignition switch is turned
ON, engine stopped or engine stalled.
Fuel Pump Relay Inspection
Measure the voltage between the ECM terminal No. 33 and Ground.
Ignition Switch : ON
0v(for1~2sec.)
Cranking0v
M161 ENGINE CONTROLS 1F2 -- 47
D AEW OO M Y_2000
KAB1F460
Failure
CodeDescriptionTrouble AreaMaintenance Hint
72No. 1 injector short
circuit to battery
When malfunction of injector
circuit
Injector #1 short circuit to
powerDInspection the power to injector #1 or
bad contact
DInspection the injector
DInspection the ECM
73No. 1 injector short
circuit to ground or open
When malfunction of injector
circuit
Injector #1 short circuit to
ground or openDInspection the ECM pin 63 about short
circuit or open with bad contact
DInspection the injector
DInspection the ECM
74No. 2 injector short
circuit to battery
When malfunction of injector
circuit
Injector #2 short circuit to
powerDInspection the power to injector #2 or
bad contact
DInspection the injector
DInspection the ECM
75No. 2 injector short
circuit to ground or open
When malfunction of injector
circuit
Injector #2 short circuit to
ground or openDInspection the ECM pin 64 about short
circuit or open with bad contact
DInspection the injector
DInspection the ECM
76No. 3 injector short
circuit to battery
When malfunction of injector
circuit
Injector #3 short circuit to
powerDInspection the power to injector #3 or
bad contact
DInspection the injector
DInspection the ECM
1F2 -- 48 M161 ENGINE CONTROLS
D AEW OO M Y_2000
Failure
CodeDescriptionTrouble AreaMaintenance Hint
77No. 3 injector short
circuit to ground or open
When malfunction of injector
circuit
Injector #3 short circuit to
ground or openDInspection the ECM pin 65 about short
circuit or open with bad contact
DInspection the injector
DInspection the ECM
78No. 4 injector short
circuit to battery
When malfunction of injector
circuit
Injector #4 short circuit to
powerDInspection the power to injector #4 or
bad contact
DInspection the injector
DInspection the ECM
79No. 4 injector short
circuit to ground or open
When malfunction of injector
circuit
Injector #4 short circuit to
ground or openDInspection the ECM pin 66 about short
circuit or open with bad contact
DInspection the injector
DInspection the ECM
YAA1F420YAA1F430
Injector Spray Pattern Check
1. Turn the ignition switch OFF.
2. Remove the fuel injector connectors.
3. Remove the fuel distributor and injector with a unit. At this time, do not remove the supply and return line.
Notice:Prepare the beaker for taking the fuel.
4. Connect the shop made cable to the injector with a firing order.
5. Connect the other end of shop made cable to the positive battery cable and negative battery cable.
6. Turn the ignition switch ON.
7. Check the injector for normal spray pattern as shown in the figure. Check injector for leaks or later drop
Injector Resistance Inspection
1. Turn the ignition switch OFF.
2. Remove the fuel injector connectors.
3. Measure the fuel injector coil resistance using a multimeter.
Specified Value
14 ~ 17Ω
Notice:Replace the fuel injector if the measured value is out of the specified values. Check the connector and wire
connection between the ECM and the injector if the measured values are normal.
M161 ENGINE CONTROLS 1F2 -- 51
D AEW OO M Y_2000
KAB1F230
Failure
CodeDescriptionTrouble AreaMaintenance Hint
40Purge control valve
short circuit to batteryWhen short circuit to power
sourceDInspection the ECM pin 34 about short
circuitoropenwithbadcontact
41
Purge control valve
short circuit to ground or
openWhen short circuit to ground or
open
circuitor open withbadcontact
DInspection the source power of valve
DInspection the purge control solenoid
vale
54Purge control circuit
malfunctionWhen malfunction of purge
control : not workvale
DInspection the ECM
Test
YAA1F460
1. Maintain the normal temperature and idling state by
operating the engine.
2. Connect the ECM terminal No. 11 and No. 34 and
check for normal operation through the output waves
using oscilloscope.Notice:Test during purge control valve operation after
the minimum of 1 minute after the engine turned on.
3. Connect the ECM terminal No. 34 and No.10 and
check for current consumption during the ignition
switch ON.
Specified Value
0.3 ~ 0.5 A
4. Remove the line to canister and measure the pres-
sure with the vacuum pressure gauge.
Specified Value
> 500 mbar
(after approx. 1 min.)
purge control valve operates
at this time
Notice:Test while at normal temperature and at idling
state by operating the engine.
M161 ENGINE CONTROLS 1F2 -- 57
D AEW OO M Y_2000
KAB1F240
Failure
CodeDescriptionTrouble AreaMaintenance Hint
104Throttle position sensor
1 low voltageTPS 1 short circuit to ground
or open
105Throttle position sensor
1 high voltageTPS 1 short circuit to power
108Throttle position sensor
2 low voltageTPS 2 short circuit to ground
or open
109Throttle position sensor
2 high voltageTPS 2 short circuit to powerDMonitoring the actual values through
scantool
116Throttle actuator
learning control failureWhen actuator adaption
fluctuation or not meet the
conditionscantool
DInspection the ECM pin 84, 85, 87,
112, 67, 68 about short circuit or open
with bad contact
119Throttle valve return
spring failureWhen return spring defective
of actuator
withbadcontact
DInspection the throttle valve actuator
DInspection the ECM
121Throttle actuator failureWhen supply voltage of the
actuator short circuit to power
InspectiontheECM
123
Different mass air flow
sensor signal with
throttle position sensorWhen shut down of output
driver
125Both throttle position
sensor failureWhen defective of both
potentiometers
1F2 -- 58 M161 ENGINE CONTROLS
D AEW OO M Y_2000
Failure
CodeDescriptionTrouble AreaMaintenance Hint
126
Throttle position sensor
1 not plausible with
Throttle position sensor
2
When difference between
TPS 1 and TPS 2DMonitoring the actual values through
scan tool
DIns
pection the ECMpin 84, 85, 87,
127High permanent throttle
signalWhen failure of wiring
harness or actuator
DInspectiontheECMpin84,85,87,
112, 67, 68 about short circuit or open
with bad contact
Itiththttlltt
185
Mass air flow sensor
and throttle position
sensor failureWhen difference between
MAF and TPS signal
DInspection the throttle valve actuator
DInspection the ECM
Circuit Description
The ECM supplies a 5 volt reference signal and a ground to the TP sensor. The TP sensor sends a voltage signal back
to the ECM relative to the throttle plate opening. The voltage signalwill vary from approximately 0.3 ~ 0.9 volts at
closed throttle, to over 4.0 ~ 4.6 volts at Wide Open Throttle (WOT).
The TP sensors serve for engine load control according to the drive pedal command. Load adjustments independent of
the drive pedal command can be implemented; such functions are, for instance, idle control, speed control, drive slip
control, load shock damping, and similar functions.
When the actuator current fails, the throttle valve is returned to emergency operating position by a spring. The throttle
valve position, thereby the actuator drive position checkback is provided by two potentiometers. The motor positions
the throttle valve against the return spring force. Motor and return spring are two separate energy sources. Each of
them is able to position the throttle valve in emergency position alone. Throttle valve position checkback and monitor-
ing is provided by two actual value potentiometers connected to the engine control electronics.
Throttle Actuator Inspection
1. Turn the ignition switch to “ON” position.
2. Measure the TPS 1 signal voltage at the ECM pin No. 87 and TPS 2 signal voltage at the ECM pin No. 85.
Pedal PositionSpecified Value
TPS1Closed0.3 ~ 0.9 vTPS1Opened4.0 ~ 4.6 v
TPS2Closed4.0 ~ 4.6 vTPS2Opened0.3 ~ 0.9 v
Throttle Actuator DC Motor Inspection
1. Turn the ignition switch to “ON” position.
2. Measure the signal voltage between the ECM pin No. 67 and No. 68.
Application
Specified Value
Ignition “ON”0.8 ~ 2.3 v
Engine StatusIdling1.0 ~ 2.5 v
(Coolant temperature is over 70°C)
Throttle Actuator DC Motor Resistance
1. Turn the ignition switch to “OFF” position.
2. Measure the resistance between the ECM pin No. 67 and No. 68.
Specified Value
<10Ω
1F2 -- 62 M161 ENGINE CONTROLS
D AEW OO M Y_2000
KAB1F250
Failure
CodeDescriptionTrouble AreaMaintenance Hint
03Intake air temperature
sensor low voltageIAT sensor short circuit to
ground or openDMonitoring the actual air temperature
throu
gh scan tool
04Intake air temperature
sensor high voltageIAT sensor short circuit to
power
throughscantool
DInspection the ECM pin 80, 79 about
short circuit or open with bad contact
05Intake air temperature
sensor plausibilityMalfunction in recognition of
IAT
When functional problem
p
DInspection the IAT sensor (integrated
in HFM sensor)
DInspection the ECM
09Mass air flow sensor
plausibilityMalfunction in recognition of
MAF
When air mass not plausibleDMonitoring the actual air mass flow
through scan tool
DIns
pection the ECMpin 81, 105 about
10Mass air flow sensor low
voltageMAF sensor short circuit to
ground or open
DInspectiontheECMpin81,105about
short circuit or open with bad contact
DInspection the MAF sensor (integrated
iHFM)
11Mass air flow sensor
high voltageMAF sensor short circuit to
powerin HFM sensor)
DInspection the ECM
Circuit Description
The heated element on the MAF is a platinum film resistor (heater). It is located on a ceramic plate together with the
other elements in the bridge circuit. The temperature sensitive resistor (flow sensor) also included in the bridge. The
separation of heater and flow sensor facilitates design of the control circuitry. Saw cuts are employed to ensure thermal
decoupling between the heating element and the intake air temperature (IAT) sensor. The complete control circuitry is
located on a single layer. The voltage at the heater provides the index for the mass air flow. The MAF’s electronic
circuitry then converts the voltage to a level suitable for processing in the ECM. This device does not need a burn off
process to maintain its measuring precision over an extended period. In recognition of the fact that most deposits
collect on the sensor element’s leading edge, the essential thermal transfer elements are located downstream on the
ceramic layer. The sensor element is also design to ensure that depositswill not influence the flow pattern around the
sensor.
The IAT sensor uses a thermistor to control the signal voltage to the ECM. The ECM supplies 5 volt reference and a
ground to the sensor. When the air is cold, the resistance is high; therefore the IAT signal voltagewill be high. If the
intake air is warm, resistance is low; therefore the IAT signal voltagewill be low.