2003 DAEWOO MATIZ turn signal

1D–4 ENGINE COOLING
DAEWOO M-150 BL2
The main fan size is 320 mm (12.6 in.) in diameter with
seven blades(k) to aid the air flow through the radiator
and the condenser. An electric motor(l) attached to the
radiator support drives the fan.
A/C OFF or Non-A/C Model
The cooling fan is actuated by the electronic control
module (ECM) using a low speed cooling fan relay
and a high speed cooling fan relay. On A/C equipped
vehicles, a series/parallel cooling fan relay is also
used.
The ECM will turn the cooling fan on at low speed
when the coolant temperature reaches 93
C (199
F)
and high speed at 100
C (212
F).
The ECM will change the cooling fan from high speed
to low speed at 97
C (207
F) and turn the cooling
fans off at 90
C (194
F).
A/C ON
The ECM will only turn the cooling fan on at high
speed when the A/C system is on regardless of any
condition.
ENGINE COOLANT TEMPERATURE
SENSOR
The engine coolant temperature (ECT) sensor (n) uses
a thermistor to control the signal voltage to the engine
control module (ECM).
D102D004
COOLANT TEMPERATURE SENSOR
The coolant temperature sensor(m) controls the instru-
ment panel temperature indicator. The coolant tempera-
ture sensor is located on the distributor case with the
ECT sensor on an SOHC engine.

ENGINE CONTROLS 1F–5
DAEWOO M-150 BL2
fuel is delivered under one of several conditions, called
“modes.’’
Starting Mode
When the ignition is turned ON, the ECM turns the fuel
pump relay on for 2 seconds. The fuel pump then builds
fuel pressure. The ECM also checks the Engine Coolant
Temperature (ECT) sensor and the Throttle Position
(TP) sensor and determines the proper air/fuel ratio for
starting the engine. The ECM controls the amount of
fuel delivered in the starting mode by changing how long
the fuel injector is turned on and off. This is done by
“pulsing’’ the fuel injectors for very short times.
Run Mode
The run mode has two conditions called “open loop’’ and
“closed loop.’’
Open Loop
When the engine is first started and it is above 400 rpm,
the system goes into “open loop’’ operation. In “open
loop,’’ the ECM ignores the signal from the O2S and cal-
culates the air/fuel ratio based on inputs from the ECT
sensor and the MAP sensor. The ECM stays in ”open
loop” until the following conditions are met:

The O2S has a varying voltage output, showing that it
is hot enough to operate properly.

The ECT sensor is above a specified temperature.

A specific amount of time has elapsed after starting
the engine.
Closed Loop
The specific values for the above conditions vary with
different engines and are stored in the Electronically
Erasable Programmable Read-Only Memory (EE-
PROM). When these conditions are met, the system
goes into “closed loop” operation. In “closed loop,” the
ECM calculates the air/fuel ratio (fuel injector on-time)
based on the signals from the oxygen sensors. This al-
lows the air/fuel ratio to stay very close to 14.7 to 1.
Acceleration Mode
The ECM responds to rapid changes in throttle position
and airflow and provides extra fuel.
Deceleration Mode
The ECM responds to changes in throttle position and
airflow and reduces the amount of fuel. When decelera-
tion is very fast, the ECM can cut off fuel completely for
short periods of time.
Battery Voltage Correction Mode
When battery voltage is low, the ECM can compensate
for a weak spark delivered by the ignition module by us-
ing the following methods:

Increasing the fuel injector pulse width.

Increasing the idle speed rpm.

Increasing the ignition dwell time.
Fuel Cut-Off Mode
No fuel is delivered by the fuel injectors when the ignition
is off. This prevents dieseling or engine run-on. Also, the
fuel is not delivered if there are no reference pulses re-
ceived from the CKP sensor. This prevents flooding.
EVAPORATIVE EMISSION CONTROL
SYSTEM OPERATION
The basic Evaporative Emission (EVAP) control system
used is the charcoal canister storage method. This
method transfers fuel vapor from the fuel tank to an acti-
vated carbon (charcoal) storage canister which holds
the vapors when the vehicle is not operating. When the
engine is running, the fuel vapor is purged from the car-
bon element by intake airflow and consumed in the nor-
mal combustion process.
Gasoline vapors from the fuel tank flow into the tube la-
beled TANK. These vapors are absorbed into the car-
bon. The canister is purged by Engine Control Module
(ECM) when the engine has been running for a specified
amount of time. Air is drawn into the canister and mixed
with the vapor. This mixture is then drawn into the intake
manifold.
The ECM supplies a ground to energize the controlled
charcoal canister purge solenoid valve. This valve is
Pulse Width Modulated (PWM) or turned on and off sev-
eral times a second. The controlled charcoal canister
purge PWM duty cycle varies according to operating
conditions determined by mass airflow, fuel trim, and in-
take air temperature.
Poor idle, stalling, and poor driveability can be caused
by the following conditions:

An inoperative controlled canister purge valve.

A damaged canister.

Hoses that are split, cracked, or not connected to the
proper tubes.
CONTROLLED CHARCOAL
CANISTER
The controlled charcoal canister is an emission control
device containing activated charcoal granules. The con-
trolled charcoal canister is used to store fuel vapors from
the fuel tank. Once certain conditions are met, the En-
gine Control Module (ECM) activates the controlled
charcoal canister purge solenoid, allowing the fuel va-
pors to be drawn into the engine cylinders and burned.
POSITIVE CRANKCASE
VENTILATION CONTROL SYSTEM
OPERATION
A Positive Crankcase Ventilation (PCV) control system
is used to provide complete use of the crankcase va-

1F–6 ENGINE CONTROLS
DAEWOO M-150 BL2
pors. Fresh air from the air cleaner is supplied to the
crankcase. The fresh air is mixed with blowby gases
which then pass through a vacuum hose into the intake
manifold.
Periodically inspect the hoses and the clamps. Replace
any crankcase ventilation components as required.
A restricted or plugged PCV hose may cause the follow-
ing conditions:

Rough idle

Stalling or low idle speed

Oil leaks

Oil in the air cleaner

Sludge in the engine
A leaking PCV hose may cause the following conditions:

Rough idle

Stalling

High idle speed
ENGINE COOLANT TEMPERATURE
SENSOR
The Engine Coolant Temperature (ECT) sensor is a
thermistor (a resistor which changes value based on
temperature) mounted in the engine coolant stream.
Low coolant temperature produces a high resistance
(100,000 ohms at –40C [–40F]) while high tempera-
ture causes low resistance (70 ohms at 130C [266F]).
The Engine Control Module (ECM) supplies 5 volts to
the ECT sensor through a resistor in the ECM and mea-
sures the change in voltage. The voltage will be high
when the engine is cold and low when the engine is hot.
By measuring the change in voltage, the ECM can de-
termine the coolant temperature. The engine coolant
temperature affects most of the systems that the ECM
controls. A failure in the ECT sensor circuit should set a
Diagnostic Trouble Code (DTC) P0117 or P0118. Re-
member, these DTC indicate a failure in the ECT circuit,
so proper use of the chart will lead either to repairing a
wiring problem or to replacing the sensor to repair a
problem properly.
THROTTLE POSITION SENSOR
The Throttle Position (TP) sensor is a potentiometer
connected to the throttle shaft of the throttle body. The
TP sensor electrical circuit consists of a 5-volt supply
line and a ground line, both provided by the Engine Con-
trol Module (ECM). The ECM calculates the throttle
position by monitoring the voltage on this signal line. The
TP sensor output changes as the accelerator pedal is
moved, changing the throttle valve angle. At a closed
throttle position, the output of the TP sensor is low,
about 0.4–0.8 volt. As the throttle valve opens, the out-
put increases so that, at Wide Open Throttle (WOT), the
output voltage will be about 4.5–5 volts.The ECM can determine fuel delivery based on throttle
valve angle (driver demand). A broken or loose TP sen-
sor can cause intermittent bursts of fuel from the injector
and an unstable idle, because the ECM thinks the
throttle is moving. A problem in any of the TP sensor cir-
cuits should set a Diagnostic Trouble Code (DTC)
P0122 or P0123. Once the DTC is set, the ECM will sub-
stitute a default value for the TP sensor and some ve-
hicle performance will return.
CATALYST MONITOR OXYGEN
SENSORS
Three-way catalytic converters are used to control emis-
sions of hydrocarbons (HC), carbon monoxide (CO),
and oxides of nitrogen (NOx). The catalyst within the
converters promotes a chemical reaction. This reaction
oxidizes the HC and CO present in the exhaust gas and
converts them into harmless water vapor and carbon
dioxide. The catalyst also reduces NOx by converting it
to nitrogen. The ECM can monitor this process using the
oxygen sensor (O2S) and heated oxygen sensor
(HO2S). These sensors produce an output signal which
indicates the amount of oxygen present in the exhaust
gas entering and leaving the three-way converter. This
indicates the catalyst’s ability to efficiently convert ex-
haust gasses. If the catalyst is operating efficiently, the
O2S signals will be more active than the signals pro-
duced by the HO2S. The catalyst monitor sensors oper-
ate the same way as the fuel control sensors. The
sensors’ main function is catalyst monitoring, but they
also have a limited role in fuel control. If a sensor output
indicates a voltage either above or below the 450 mV
bias voltage for an extended period of time, the Engine
Control Module (ECM) will make a slight adjustment to
fuel trim to ensure that fuel delivery is correct for catalyst
monitoring.
A problem with the O2S circuit will set DTC P0131,
P0132, P0133 or P0134 depending on the special condi-
tion. A problem with the HO2S signal will set DTC
P0137, P0138, P0140 or P0141 depending on the spe-
cial condition.
A fault in the heated oxygen sensor (HO2S) heater ele-
ment or its ignition feed or ground will result in lower oxy-
gen sensor response. This may cause incorrect catalyst
monitor diagnostic results.
ELECTRIC EXHAUST GAS
RECIRCULATION VALVE
The Electric Exhaust Gas Recirculation (EEGR) system
is used on engines equipped with an automatic trans-
axle to lower oxides of nitrogen (NOx) emission levels
caused by high combustion temperature. The main ele-
ment of the system is the EEGR valve, controlled electri-
cally by the Engine Control Module (ECM). The EEGR
valve feeds small amounts of exhaust gas into the intake

1F–8 ENGINE CONTROLS
DAEWOO M-150 BL2
tions. With the ignition ON and the engine not running,
the Engine Control Module (ECM) will read the manifold
pressure as barometric pressure and adjust the air/fuel
ratio accordingly. This compensation for altitude allows
the system to maintain driving performance while hold-
ing emissions low. The barometric function will update
periodically during steady driving or under a wide open
throttle condition. In the case of a fault in the barometric
portion of the MAP sensor, the ECM will set to the de-
fault value.
A failure in the MAP sensor circuit sets a diagnostic
trouble codes P0107, P0108 or P0106.
ENGINE CONTROL MODULE
The Engine Control Module (ECM), is the control center
of the fuel injection system. It constantly looks at the in-
formation from various sensors and controls the sys-
tems that affect the vehicle’s performance. The ECM
also performs the diagnostic functions of the system. It
can recognize operational problems, alert the driver
through the Malfunction Indicator Lamp (MIL), and store
diagnostic trouble code(s) which identify the problem
areas to aid the technician in making repairs.
There are no serviceable parts in the ECM. The calibra-
tions are stored in the ECM in the Programmable Read
Only Memory (PROM).
The ECM supplies either 5 or 12 volts to power the sen-
sors or switches. This is done through resistance in the
ECM which are so high in value that a test light will not
come on when connected to the circuit. In some cases,
even an ordinary shop voltmeter will not give an accu-
rate reading because its resistance is too low. You must
use a digital voltmeter with a 10 megohm input imped-
ance to get accurate voltage readings. The ECM con-
trols output circuits such as the fuel injectors, the Idle Air
Control (IAC) valve, the A/C clutch relay, etc., by control-
ling the ground circuit through transistors or a device
called a “quad-driver.”
FUEL INJECTOR
The Multi-port Fuel Injection (MFI) assembly is a sole-
noid-operated device controlled by the Engine Control
Module (ECM) that meters pressurized fuel to a single
engine cylinder. The ECM energizes the fuel injector or
solenoid to a normally closed ball or pintle valve. This al-
lows fuel to flow into the top of the injector, past the ball
or pintle valve, and through a recessed flow director
plate at the injector outlet.
The director plate has six machined holes that control
the fuel flow, generating a conical spray pattern of finely
atomized fuel at the injector tip. Fuel from the tip is di-
rected at the intake valve, causing it to become further
atomized and vaporized before entering the combustion
chamber. A fuel injector which is stuck partially open
would cause a loss of fuel pressure after the engine is
shut down. Also, an extended crank time would be no-
ticed on some engines. Dieseling could also occur be-cause some fuel could be delivered to the engine after
the ignition is turned off.
FUEL CUT-OFF SWITCH
The fuel cutoff switch is a safety device. In the event of a
collision or a sudden impact, it automatically cuts off the
fuel supply and activates the door lock relay. After the
switch has been activated, it must be reset in order to
restart the engine. Reset the fuel cutoff switch by press-
ing the rubber top of the switch. The switch is located
near the right side of the passenger’s seat.
KNOCK SENSOR
The knock sensor detects abnormal knocking in the en-
gine. The sensor is mounted in the engine block near the
cylinders. The sensor produces an AC output voltage
which increases with the severity of the knock. This sig-
nal is sent to the Engine Control Module (ECM). The
ECM then adjusts the ignition timing to reduce the spark
knock.
VARIABLE RELUCTANCE (VR)
SENSOR
The variable reluctance sensor is commonly refered to
as an “inductive” sensor.
The VR wheel speed sensor consists of a sensing unit
fixed to the left side front macpherson strut, for non-ABS
vehicle.
The ECM uses the rough road information to enable or
disable the misfire diagnostic. The misfire diagnostic
can be greatly affected by crankshaft speed variations
caused by driving on rough road surfaces. The VR sen-
sor generates rough road information by producing a
signal which is proportional to the movement of a small
metal bar inside the sensor.
If a fault occurs which causes the ECM to not receive
rough road information between 30 and 70 km/h (1.8
and 43.5 mph), Diagnostic Trouble Code (DTC) P1391
will set.
OCTANE NUMBER CONNECTOR
The octane number connector is a jumper harness that
signal to the engine control module (ECM) the octane
rating of the fuel.
The connector is located on the next to the ECM. There
are two different octane number connector settings
available. The vehicle is shipped from the factory with a
label attached to the jumper harness to indicate the oc-
tane rating setting of the ECM. The ECM will alter fuel
delivery and spark timing based on the octane number
setting. The following table shows which terminal to
jump on the octane number connector in order to
achieve the correct fuel octane rating. Terminal 2 is
ground on the octane number connector. The find the

ENGINE CONTROLS 1F–15
DAEWOO M-150 BL2
made to enter DTC numbers for tests which the diag-
nostic executive does not recognize, the requested in-
formation will not be displayed correctly and the scan
tool may display an error message. The same applies to
using the DTC trigger option in the Snapshot mode. If an
invalid DTC is entered, the scan tool will not trigger.
Failed Last Test
This message display indicates that the last diagnostic
test failed for the selected DTC. For type A, B and E
DTCs, this message will be displayed during subse-
quent ignition cycles until the test passes or DTCs are
cleared. For type C and type D DTCs, this message will
clear when the ignition is cycled.
Failed Since Clear
This message display indicates that the DTC has failed
at least once within the last 40 warm-up cycles since the
last time DTCs were cleared.
Failed This Ig. (Failed This Ignition)
This message display indicates that the diagnostic test
has failed at least once during the current ignition cycle.
This message will clear when DTCs are cleared or the
ignition is cycled.
History DTC
This message display indicates that the DTC has been
stored in memory as a valid fault. A DTC displayed as a
History fault may not mean that the fault is no longer
present. The history description means that all the con-
ditions necessary for reporting a fault have been met
(maybe even currently), and the information was stored
in the control module memory.
MIL Requested
This message display indicates that the DTC is currently
causing the MIL to be turned ON. Remember that only
type A B and E DTCs can request the MIL. The MIL re-
quest cannot be used to determine if the DTC fault con-
ditions are currently being experienced. This is because
the diagnostic executive will require up to three trips dur-
ing which the diagnostic test passes to turn OFF the
MIL.
Not Run Since CI (Not Run Since Cleared)
This message display indicates that the selected diag-
nostic test has not run since the last time DTCs were
cleared. Therefore, the diagnostic test status (passing
or failing) is unknown. After DTCs are cleared, this mes-
sage will continue to be displayed until the diagnostic
test runs.
Not Run This Ig. (Not Run This Ignition)
This message display indicates that the selected diag-
nostic test has not run during this ignition cycle.
Test Ran and Passed
This message display indicates that the selected diag-
nostic test has done the following:
Passed the last test.

Run and passed during this ignition cycle.

Run and passed since DTCs were last cleared.
If the indicated status of the vehicle is “Test Ran and
Passed” after a repair verification, the vehicle is ready to
be released to the customer.
If the indicated status of the vehicle is “Failed This Igni-
tion” after a repair verification, then the repair is incom-
plete and further diagnosis is required.
Prior to repairing a vehicle, status information can be
used to evaluate the state of the diagnostic test, and to
help identify an intermittent problem. The technician can
conclude that although the MIL is illuminated, the fault
condition that caused the code to set is not present. An
intermittent condition must be the cause.
PRIMARY SYSTEM-BASED
DIAGNOSTICS
There are primary system-based diagnostics which
evaluate the system operation and its effect on vehicle
emissions. The primary system-based diagnostics are
listed below with a brief description of the diagnostic
function:
Oxygen Sensor Diagnosis
The fuel control oxygen sensor (O2S) is diagnosed for
the following conditions:

Few switch count (rich to lean or lean to rich).

Slow response (average transient time lean to rich or
rich to lean).

Response time ratio (ratio of average transient time
rich(lean) to lean(rich)).

Inactive signal (output steady at bias voltage approxi-
mately 450 mV).

Signal fixed high.

Signal fixed low.
The catalyst monitor heated oxygen sensor (HO2S) is
diagnosed for the following conditions:

Heater performance (current during IGN on).

Signal fixed low during steady state conditions or
power enrichment (hard acceleration when a rich mix-
ture should be indicated).

Signal fixed high during steady state conditions or de-
celeration mode (deceleration when a lean mixture
should be indicated).

Inactive sensor (output steady at approx. 438 mV).
If the O2S pigtail wiring, connector or terminal are dam-
aged, the entire O2S assembly must be replaced. Do
not attempt to repair the wiring, connector or terminals.
In order for the sensor to function properly, it must have
clean reference air provided to it. This clean air refer-
ence is obtained by way of the O2S wire(s). Any attempt
to repair the wires, connector or terminals could result in

1F–22 ENGINE CONTROLS
DAEWOO M-150 BL2
Multiple ECM Information Sensor DTCs Set
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Is the check complete.
–
Go to Step 2
Go to “Euro
On-Board
Diagnostic
System Check”
2
1. Turn the ignition OFF and disconnect the Engine
Control Module (ECM).
2. Turn the ignition ON and check the 5 volt
reference circuit for the following conditions:

Poor connection at the ECM.

Open between the ECM connector affected
sensors shorted to ground or voltage.
3. If a problem is found, locate and repair the open
or short circuit as necessary.
Is a problem found?
–
Go to Step 19Go to Step 3
3
1. Check the sensor ground circuit for the following
conditions:

Poor connection at the ECM or affected
sensors.

Open between the ECM connector and the
affected sensors.
2. If a problem is found, repair it as necessary.
Is a problem found?
–
Go to Step 19Go to Step 4
4
Measure the voltage of the Electric Exhaust Gas
Recirculation (EEGR) Pintle Position Sensor signal
circuit between ECM harness connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 5Go to Step 9
5
Measure the voltage of the Manifold Absolute
Pressure (MAP) sensor signal circuit between the
ECM harness connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 6Go to Step 11
6
Measure the voltage of the Throttle Position (TP)
sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 7Go to Step 12
7
Measure the voltage of the Intake Air Temperature
(IAT) sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 8Go to Step 13
8
Measure the voltage of the Engine Coolant
Temperature (ECT) sensor signal circuit between the
ECM harness connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 16Go to Step 14
9
1. Disconnect the EEGR valve.
2. Measure the voltage of the EEGR Pintle Position
sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 10Go to Step 15
10Replace the EEGR valve.
Is the repair complete?–Go to Step 19–
11
Locate and repair the short to voltage in the MAP
sensor signal circuit.
Is the repair complete?
–
Go to Step 19
–

1F–58 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F060
DIAGNOSTIC TROUBLE CODE (DTC) – P0107
MANIFOLD ABSOLUTE PRESSURE SENSOR LOW VOLTAGE
Circuit Description
The engine control module (ECM) uses the Manifold Ab-
solute Pressure (MAP) sensor to control the fuel deliv-
ery and the ignition timing. The MAP sensor measures
the changes in the intake manifold pressure, which re-
sults from engine load (intake manifold vacuum) and the
rpm changes; and converts these into voltage outputs.
The ECM sends a 5 volt-reference voltage to the MAP
sensor. As the manifold pressure changes, the output
voltage of the MAP sensor also changes. By monitoring
the MAP sensor output voltage, the ECM knows the
manifold pressure. A low-pressure (low voltage) output
voltage will be about 1.0 to 1.5 volts at idle, while higher
pressure (high voltage) output voltage will be about 4.5
to 5.0 at wide open throttle (WOT). The MAP sensor is
metric pressure, allowing the ECM to make adjustments
for different altitudes.
Conditions for Setting the DTC

This DTC can be stored in “key-on” status.
(Case A)

When the engine idling.

No throttle position(TP) sensor fail conditions pres-
ent.

Engine speed(rpm) is less than 2,500rpm.

The MAP is less than 15kPA.
(Case A)

When the engine part load.

The engine revolution speed is less than 4,000rpm.

No Throttle Position (TP) Sensor fails conditions
present.

The Throttle Position (TP) angle greather than 20.0
The MAP is less than 15 kPA.
An open or low voltage condition exists.
Action Taken when the DTC Sets

The Malfunction Indicator Lamp (MIL) will illuminate.

The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored in
the Freeze Frame and Failure Records buffers.

A history DTC is stored.

The coolant fan turns ON.

The ECM will substitutes a fixed MAP value and use
TP to control the fuel delivery (the scan tool will not
show defaulted)
Conditions for Clearing the MIL/DTC

The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.

A history DTC will clear after 40 consecutive warm-up
cycles without a fault.

DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
With the ignition ON and the engine stopped, the man-
ifold pressure is equal to atmosphere pressure and the
signal voltage will be high.
The ECM as an indication of vehicle altitude uses this
information. Comparison of this reading with a known
good vehicle with the same sensor is a good way to
check the accuracy of a suspect sensor. Readings
should be the same ±0.4volt.
If a DTC P 0107 is intermittent, refer to “Manifold Abso-
lute Pressure Check” in this Section for further diagno-
sis.

ENGINE CONTROLS 1F–59
DAEWOO M-150 BL2
If the connections are OK monitor the manifold absolute
pressure (MAP) sensor signal voltage while moving re-
lated connectors and the wiring harness. If the failure isinduced, the display on the scan tool will change. This
may help to isolate the location of an intermittent mal-
function.
DTC P0107 – Manifold Absolute Pressure Sensor Low Voltage
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Is the system check complete?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Connect the scan tool to the data link connector
(DLC).
2. Turn the ignition switch to ON.
Does the scan tool show the manifold absolute
pressure (MAP) sensor voltage above the value
specified?
4VGo to Step 3Go to Step 4
3
1. Disconnect the vacuum line from the MAP
sensor.
2. Apply 88kPA (20in.of Hg) of vacuum to the MAP
sensor.
Does the scan tool show the MAP sensor voltage
within the value specified?
1.0–1.5V
Go to
“Diagnostic
Aids”
Go to Step 4
4
1. Turn the ignition switch to LOCK.
2. Disconnect the MAP sensor connector.
3. Turn the ignition switch to ON.
4. Measure the voltage between the MAP sensor
connector terminals A and C.
Does the voltage measure within the value
specified?
4.5–5.0VGo to Step 5Go to Step 6
5
Connect a fused jumper between the MAP sensor
connector terminals B and C.
Does the scan tool show the MAP sensor voltage
above the value specified?
4VGo to Step 11Go to Step 9
6
Measure the voltage between the MAP sensor
connector terminal A and ground.
Does the voltage measure within the value
specified?
4.5–5.0VGo to Step 7Go to Step 8
7
1. Turn the ignition switch to LOCK.
2. Check for open wires between the MAP sensor
connector terminal A and the ECM connector
terminal 78.
Is the problem found?
–
Go to Step 10Go to Step 12
8
1. Turn the ignition switch to LOCK.
2. Check for an open or short to ground in the wire
between the MAP sensor connector terminal C
and the ECM connector terminal 12.
Is the problem found ?
–
Go to Step 10Go to Step 12
9
1. Turn the ignition switch to LOCK.
2. Check for an open or short to ground in the wire
between the MAP sensor connector terminal B
and the ECM connector terminal 73.
Is the problem found ?
–
Go to Step 10Go to Step 12